MVCC Battalion Comm Center Apr 2012 N6CC

The Military Vehicle Collectors of California held their annual Camp Delta Rally and campout the week of 15-22 April 2012.  This is the largest military vehicle gathering in the West and is held at Camp Delta at Tower Park near Lodi CA.  The site is the KOA campground off Highway 12, five miles west of the intersection with I-5.  There are usually over 200 military vehicles of all types in attendance, many with the correct vintage radio equipment installed.  Included were militaria displays, living history demonstrations, Civil War units, a large flea market, classic movies and good chow.  As with past MVCC rally’s, the West Coast Military Radio Collectors Group set up, operate and display a range of vintage military radio communications equipment.  In addition to the usual live operation of our station equipment, we had a PRD-1 HF radio direction finder up and running. Photos of past operations can be viewed in the Radio News category of this Blog.

PRD-1 radio Direction Finder Batt Comm Cen N6CC

A variety of military vehicles were found in every direction.

Battalion Comm Center: Part of HF and VHF Commo Positions - N6CC

The FRAG Order with details of the equipment, frequencies and operations planned for April 2012 is below:

FRAGO REVA

FRAGO REV A2

NO Parking. Seriously.

Well, lets start here because this is one place the boats communicated with (and this site is about Combat Comms!).  We built a shore Comm Center in the Great Lakes Naval Base boat house, headquarters for CRD21.  Circa early 1973. Not many rules so we got creative ordering equipment through regular supply channels, visiting the base salvage area and generally “comshawing” anything we needed.  It helped that the Navy’s Electronic Technician Class “A” School was at Great Lakes.  The result was a pretty good setup that worked well.

As a tactical boat unit, we had no means to transmit or receive Record Traffic (hard-copy Naval Messages) aboard the boats.  Since our shore base HQ was technically “temporary” (we could not take it with us) we had no record traffic capability there either.  We were serviced by the Naval Training Center Comm Center who provided that service for us.  We had the radio gear but a mechanical teletype machine would last about 10 seconds aboard a PTF!

We had two URC-32′s,  500 watt output, 2-30 MHz HF SSB transceivers, an R-1051 HF receiver, an SRC-20, 100 watt 225-400 MHz UHF transceiver, VRC-46/RT-524 running 35 watts, 30-75 MHz on VHF and a 25 watt Raytheon Ray-50 marine band FM radio.

Here’s a photo of Ltjg “F” clowning with one of the URC-32′s. The SRC-20 UHF transceiver is behind him.  The PRC-41 is on the floor to his left.  Photo: Tim Sammons

Here’s a shot of the VRC-46, antenna and audio patch panels, the R-1051 and the PRC-25. The Ham-M antenna rotator controller is on top of the distribution amplifier.  The chart on the wall assisted in pointing the Yagi antennas at the boats’ operating areas to optimize comms.  The deep pattern nulls from the Yagi’s allowed us to get a decent LOP (Line of Position) out to the boats if The Skipper wanted to find us out on the Lake someplace – your basic radio direction finder…. Photo: Tim Sammons

We installed a 50 foot Rohn tower on the roof sporting a vertical Cush Craft 4 element 10 meter Yagi beam, which we cut and spaced for our primary tactical freq of 39.00 MC.  Similarly, we had another vertical Cush Craft 220 yagi rebuilt for our 239.0 UHF AM freq and another 11 element Cush Craft Yagi rebuilt for 156.800 MC, Channel 16 marine band, with whips for the Ray 50 and HF transceivers.

The Yagi’s were rotated on a common mast by a Ham-M rotator, with all that equipment being bought from Amateur Electronic Supply in Milwaukee. They were surprised when we showed up in a Navy truck with a government purchase order to buy all this “Ham” stuff.  I see on Google Earth satellite photo’s that the tower is still there 38 years later.  Hope the Assault Craft Unit was able to put it to use!

The below photo shows the CRD 21 communications tower on the roof of Building 13, CRD21 Headquarters and the NTC Boathouse.  At the top is the 39 MC, 4 element Yagi.  Below that on a common crossarm is the 239 MC Yagi and the 156 MC Yagi’s.  All 3 rotated by the Ham-M rotator.  Below the rotator on a yardarm are the AS-390 UHF and 156 MC ground plane omni directional antennas.  Photo: Tim Sammons

We also had an AS-1729/VRC whip for the VRC-46. We had an HF wire dipole cut for 6970 KC, our primary HF freq although the URC-32′s were pretty forgiving when used off freq on our other tactical channels.  God bless Tube amplifiers and the URC-32 couplers!   The Division Commodores, LCDR Jim Roper and LCDR Tim Johnston had a C-1138 Remote Control and handset in their second floor office so they could radio us rudder orders (which they never did – They were great officers, leaders and bosses).

The beams were handy because we did a lot of training in the Lake Michigan Controlled Firing Area, well out in the middle of the lake, out of range of the VRC-46′s / AS-1729 whip ground wave.  The beams made the difference.

This Comm Center was designed to support our boats and ships during training work in the Great Lakes area and it performed well.  A good combination of the Navy supply system, Navy SOP and Ham Radio pragmatism operating in a “don’t tell me how, just get it done” environment.  The ET’s did a great job.  More on that later.

You can see the mortar sight quadrant near the sound-powered phone mouthpiece.  Sets azimuth and elevation, which in conjunction with range tables and the number of propellant increments clipped on, determines where the round will hit.  More or less..

It can also be fired in the conventional mortar-mode by not retracting the firing pin.  It goes off once the round contacts the pin.  A very effective weapon.  A common usage would be (at night) to fire a flare round over the target’s head, well beyond him and illuminating him from behind – then you fire your main weapons at his sillouette.  It also reduces self-illumination in that manner.

The flare fuze is set by inserting it in the fuze setter installed on the port side of the ammo ready service locker.  Rotate the round so the fuze is set to the desired time delay, pull the pin and then fire it.  One favorite “ship handling” training exercise was to try to land the burned-out flare parachute on the deck by chasing it and manovering under it.  Pretty tricky.  Photo: Tim Sammons

Below is photo sequence from another day firing the 81 mm. In this case, note that the loader had dropped the round and is protecting himself from the blast.  In the second photo the round has fired and the barrel has recoiled about 6 inches backward relative to the recoil cylinder; the round is likely still inside the barrel making its way out when the photo was taken.  Note the muzzle flash hider mounted on the .50 Cal M2 barrel  Photos: Tim Sammons

Below is a view of the 40 mm gun being fired. There is a lot going on in this photo.  EM1 “Mac” is the Trainer, slewing the mount in azimuth.  The Pointer is on the other side of the gun and he sets the elevation of the gun.  He also fires the Gun with the foot trigger.  GMG2 (SEAL) “Bob” is the Loader as he prepares to load another 4 round clip into the feeder where 8 already reside waiting to be fired.  Note that the Ensign has been tied off to prevent if from slapping the Loader in the wind.

The particular round being fired is the HE-I-T/SD (High Explosive Incendiary Tracer/Self Destruct variant.  It has a maximum range of 6 nautical miles but the maximum effective range is much shorter.  This round would self detonate at 4000-5000 yards if it didn’t hit anything first – but it still had a point-detonation fuze.  The intent in anti-aircraft service was to put out a wall of high velocity shrapnel at that range that an enemy aircraft had to fly through.  It also reduced the friendly fire potential, a serious consideration in large fleet formations under air attack.  When fired, you could see the tracer all the way out and when you hit that 55 gallon drum, a bright flash and puff of gray smoke indicated detonation.  It was also a good training round due to this “self limiting” maximum range.  The Gun fires more than 2 rounds per second and is technically a “machine cannon”, being fully automatic.   Boom boom boom boom boom boom boom boom …Serious weapon.

Often called a “Bofors” Gun it is actually a US-manufactured weapon built by Chrysler Corporation, one of about 60, 000 they made during WWII.  We redesigned it under license from Bofors (Sweden) to eliminate the numerous hand fitted, gun-specific parts that Bofors was utilizing.  “File this part to fit upon final assembly”.  This did not lend itself to mass production or field repair parts logistics, so some redesign was made.  It was also redesigned for SAE “English” tooling versus the metric dimensioning in the original Swedish design. Approximately 26 nations used this gun or close variants.  It is still in use today – including on the AC-130 Spectre Gunships.

This particular gun aboard PTF-17 was a replacement, recently arrived from the Naval Ammunition Depot, Crane Indiana.  It was still in its Haze Gray paint and was apparently someone’s Mount 212 as indicated by the stencil on the elevation spring housing.  Photo:  Tim Sammons

Fun Fact: When we received the boats at CRD21 the pointer and trainer foot rests had wooden blocks installed to better fit the shorter-statured Vietnamese. This included a wooden block on the trigger pedal. The bridge decking was also built up with nicely varnished wooded “hatch cover” plates to allow the RVN sailors to see over the dashboard.

FIREPOWER:  We carried approximately 20 M-16 Rifles, four .45 cal pistols, two .38 cal pistols, two M-60 machine guns, two M-79 grenade launchers, two M-870 12 gauge shotguns, a 40 mm Very pistol, a .45/70 line-throwing gun plus the .50 cal M2, two 20 mm cannons, the 40 mm cannon and the 81 mm mortar. Without a doubt, the most heavily armed vessel of its size anywhere. Here’s some more photos of a typical day at work.  Photo:  Tim sammons

The 20 mm guns were a bit of an enigma to me. When we received the boats from Vietnam, they had the Oerlikon 20 mm guns of WWII vintage. They were mounted on deck on either side of the bridge. This gun utilized the 60 round drum-type magazine and a reasonable photo of one is in the photo of Admiral Kauffman aboard PTF-17 on the CRD21 Ops posting. For some reason I don’t think we ever fired them, at least on PTF-17 or PTF-18 while I was aboard. It could be because we didn’t have any of the Gunners Mates with current “service record” school qualifications on them and even though the Navy’s Gunners Mate Class “A” School was at Great Lakes we may not have been qualified on them. They may have stopped teaching them at some point.

Some time during my tour we replaced the Oerlikons with the MK-16 belt-fed 20 mm guns. I remember having to modify the two armor plates from the Oerlikon mount to accommodate the MK-16′s. That required drilling new bracket holes in the plates and we must have worn out about a dozen drill bits trying to penetrate that armor plate. Tough stuff! Below is a photo of GMG2 “Jack” with the new MK-16 gun mount aboard PTF-18. Photo: Tim Sammons

While I was on active duty I don’t recall ever firing the MK-16′s either. Maybe CRD21 did after I left active duty and joined the Reserve crew in August 1975 but I don’t recall it. I have a vague memory of someone telling me that a 20 mm round detonated inside a gun, bird-caging the barrel. If that actually happened, maybe we became “gun shy” or were directed not to fire them again. Vague recollections: Any CRD21 guys recall the situation with either of these guns?

M-60 Practice.  We usually mounted the M-60′s in the searchlight pintles on either side of the bridge, over the 20 mm gun mounts. There was a cutout with a removable plywood cover in the decking for the lookouts / gunners and it was well positioned. The M-60 could be fired single-shot; it had a flat trajectory and was VERY accurate. Note the 81 mm mortar fuze setter on the ammo box (dark circle). Note the lamp assembly above the fuze opening to facilitate fuze setting in the dark. Photo:  Tim Sammons

Below: The Browning M2 .50 Cal heavy machine gun.  Another serious weapon.  After a healthy burst, the crew would light their cigarettes on the hot barrel.  If a round was still chambered after you had fired a burst, that round would eventually “cook off” from the heat retained in the chamber – very dangerous – keep the gun pointed down range at all times.  NEVER walk in front of it! On rare occasions, a .50 cal round would hit a wave face at such an angle that it would come straight back at us.  Weird. How could that happen? It sounded like a 10 pound bumble bee whizzing over your head.  Never got any dings in personnel or the boat but it was scary when it happened.  Note the lack of hearing protection – this was the “Old Navy”, not good…
Although not evident in this faded photo, the .50 Cal ammo projectiles were color coded. We usually fired a mix including – Armor Piercing, Incendiary, Tracer. This was a repeating, 5 round sequence consisting of those 3 types plus 2 Ball rounds. Bad news for bad guys…
Photo: Tim Sammons

Don’t forget the pre-firing set up of the M2 using your handy Head Space and Timing gauge – to prevent the gun from blowing up in your face. Also, never charge the weapon by grabbing the handle with your palm facing forward – a cooked off round will drive the handle rearward, shattering your wrist. Keep that palm facing you!

Below: Loading and Firing the 40 mm with ammo made in 1944.  Photo: Tim Sammons

Fun Fact: When the projectiles you see below detonated, they sprinkled fragments of steel across the bottom of Lake Michigan. Then they rusted, becoming iron ore. During the first half of the 20th century much of the iron ore (steel) used in the US armaments buildup to fight WWII came from the Mesabi Iron Range, not far from here in Minnesota and extending out into Lake Superior and into the Upper Peninsula of Michigan and Wisconsin. The worlds largest iron deposits. The 40 mm rounds you see here were manufactured in 1944. In a real sense, that iron was “going home”.

We were AWESOME !!

CRD21 was an element of Coastal River Squadron Two based at Little Creek VA.  They, in turn were an element of Naval Inshore Warfare Command Atlantic which also owned the SEAL’s, the Inshore Undersea Warfare Group and the Explosive Ordnance Disposal units of the Amphibious Forces, US Atlantic Fleet.  The Coastal River Divisions were eventually renamed Special Boat Units that morphed into today’s units still supporting Naval Special Warfare.

CRD21 was Commissioned to perform the following missions. “To maintain craft to support coastal surveillance operations; develop small boat tactics; train personnel in the operation and maintenance of coastal craft in cold weather; conduct and support special warfare and naval inshore warfare operations; conduct and support special psychological and tactical cover and deception operations; and train selected reserve component to support these tasks in the event of mobilization”

Most of the reservists and active duty crews were Vietnam Vets themselves, many with combat craft experience so it provided for a ready-made, strong team.  That included LCDR James Roper and LCDR Tim Johnston, our only two commanding officers and Division Commodores.  Great Lakes was selected as a base since it provided the only US cold weather training locale to prepare for NATO operations, one of our principal mission areas. It also had a large population of Navy veterans in the reserve.

Note: Readers are also directed to the excellent narratives of CRD21 written by LCDR Tim Johnston (CRD21 Commodore) and Master Chief Gunners Mate Bob Stoner.  Bob served with CRD21 during much  of the time I did and his carefully researched history can be found in Reference (10),  WWW.PTFNASTY.COM the excellent website by Dan Withers.  Bob covers  the history, personnel and some of the Navy’s politics in play during  that era.  He also specifically describes the PTF weapons systems as we  used them.    Commodore Johnston covered the command relationships, navy politics, unit history, overall viewpoints and The Big Picture that only the Division Commodore could have known. Bravo Zulu !

To add to that body of information, I will attempt to fill  in details on CRD21 and the PTF’s from an operational perspective.  I’ll get to training operations at Great Lakes and also describe the boats’ other specific systems in more detail.  There doesn’t seem to be much information on those boat-unique systems to be found on the Web since this all happened well before the Internet Generation was even born. So I will try to fill in what I remember from 38 years ago.

Training Operations at CRD21:

Below:  A typical day at the Office.  PTF-17, probably above 40 knots.  Photo:  Tim Sammons

PTF-17: A typical day at the office....

First, the Op Area. Lake Michigan was our primary Op area since the Naval Base was near the south end of the lake. For a lake, its pretty big – you could go 40 knots in a straight line for almost 7 hours without ever seeing land. The deepest areas of Lake Michigan were over 900 feet deep; the bottom being about 400 feet BELOW sea level. We also made trips to the other Great Lakes (except Ontario) for port visits and recruiting support.

I had a good friend who was a Supply Officer at Navy Recruiting Command Region 5  and they would pay for our fuel if we would stop at various cities around the lakes and wave the flag.  We would meet the recruiters and take their prospects out for rides.  I swore-in many future sailors on these trips.

Interestingly, we were not the first US Navy PT boats on the Great Lakes. In October, 1945 seven Elco PT boats made their way from Newport Rhode Island to Detroit via the New York barge canals and the Welland Canal around Niagara Falls. They sailed across Lake Erie for a “show the flag” visit to Detroit at the end of World War II. (Reference 24)

Here’s a new recruit being sworn-in at Fairport Harbor Ohio in July 1974. Also a good shot of our new Mk 16 Belt-fed 20 mm automatic cannon. (Pay no attention to that wolf howling at the moon – he’s not looking at YOU).   Official US Navy Photograph

Fun Fact:  Somehow the Army had good Intel on our schedule (we sure didn’t!) .  At a few stops, ARMY recruiters were there ahead of the Navy guys to tell future Army recruits about the cool Green Boats that the ARMY had!  “Join the ARMY – See the World” !! Well, we are all on the same side…. Good for them!

Here’s a cool shot of PTF-19 idling during the annual Chicago Air and Water Festival on the Chicago waterfront. We made several high speed runs past the reviewing stand and then stood out while the US Army Golden Knights parachute team flew by in their vintage C-47 with its snazzy paint job.    Apparently the National Anthem was being played at the time.   The US Navy Blue Angels also flew and we got to take their pilots for a PTF ride afterwards. Official US Navy Photograph

Fun fact: The USMC flew an early-version Harrier to the show, roaring in from the east and slowly stopping to hover over the lake in front of the grandstand on Lakeshore Drive. Jet blast downwash spray completely soaked a few thousand spectators – most of them probably loved it.

Below is a shot taken during our recruiting trip to Chicago. We were tied up forward of the USS Silversides SS-236, a famous WWII Fleet Submarine which was tied up at the Chicago Naval Pier. During her Pacific patrols, Silversides sank 23 enemy ships and damaged another 14 earning her the third highest total of any US submarine. The Silversides is now apparently moored at Muskegon, Michigan educating our citizens about the realities of WWII.

Most of our training, and all of our gunnery training was on Lake Michigan. I was told that the treaty that ended the War of 1812 stipulated the numbers and sizes of guns the US and Canada were permitted to arm vessels with on the Great Lakes.  Apparently the State Department had to work a deal with Canada to waive that treaty so we could operate and shoot on the lakes.  There were 2 gunnery training areas, one in the south-central part of the lake, maybe 20×40 miles and another further north which was bigger.  I understand that the Fox Island group at the north end of Lake Michigan had been used in WWII and later with the USS Parle reserve DE as gunnery targets.  We never shot that far north.  We were told that the “flower children” of the day were enraged that the Navy was ruining the vegetation on these islands with the gunnery.  Until someone noticed that the target islands were much more heavily vegetated than the others – nitrates in explosives make great fertilizer.

We did many beach reconnisance exercises along the shores, notably across at Muskegon, Traverse City, and beaches in northern Illinois and Wisconsin and down to Gary Indianna (where we would be out-gunned by the civilian population found there….)

When I was a kid, I grew up watching the television series Navy Log about WWII in the Pacific.  One episode was  called “A Bucket of Sand” where a UDT team was sent ashore on some enemy controlled island in the Pacific to capture a canvas bucket of sand from the beach.  This was needed so the intel guys could assess the beaches’ suitability for amphibious landings and subsequent cross-beach vehicle ops.  Subtle, important stuff.  Seemed like a perfect Op for us, so one night we snuck up on Illinios Beach State Park and sent the SEALS ashore in their rubber IBS boat to capture a bucket of sand.  Standard UDT/SEAL mission as part of beach recon and surveys.  Fun, relevant. Little did I know…….

Speaking of Underwater Demolition Teams, I was honored to meet the founder of the Navy Combat Demolition Units and Navy Explosive Ordnance Disposal,  Rear Admiral Draper Kauffman. Admiral Kauffman had an outstanding career, basically bringing British expertise in Explosive Ordnance Disposal to the US after having served in the UK as a volunteer during the German Blitz.  He defuzed the first live bomb found at Pearl Harbor (actually a 500 pound enemy bomb at the Schofield Barracks that had just missed the ammunition dump) after the attack, earning the Navy Cross.  Later, as the leader of UDT-5, he led a daylight beach reconnisance of Saipan while under heavy fire, earning his second Navy Cross. He again led the UDT teams in the Tinian, Iwo Jima and Okinawa assaults. If anyone in the world knew the true significance of a mere “Bucket of Sand”, it was him.

He went on the command destroyers, cruisers, the US Naval Academy and finally the Navy’s Ninth Naval District based at Great Lakes. It was there that I got to meet him as he took a ride aboard PTF-17. Below. Photo: Official US Navy Photograph.

Below is another Official US Navy Photograph as Mayor Richard Daley of Chicago opened up all the bridges across the Chicago River as a salute to the Navy. Apparently it snarled the early morning commute traffic so badly, it is still backed up. A third PTF is in the far right background, behind and to the right of the small boats. Photo: Official US Navy Photograph

Below is another shot of Admiral Kauffman, Mayor Daley and Commodore Roper, Chicago River. Fireboats A-Squirtin’. Photo: Official US Navy Photograph

Reserve Drill Weekends:  Since we had a large reserve crew at CRD21 and to best utilize the assets, we broke them up into a Blue and Gold crew. That meant that we were underway 2 weekends per month as they did their monthly training. We did a lot of gunnery training! Lots! We shot up a whole bunch of WWII vintage ammo and we were all impressed with its reliability. Hardly ever a hang fire. More to follow on that.

We generally followed “Fleet Exercise Publication” FXP-3, the Navy’s book of standard shipboard exercises. It contained canned exercise scenarios to work each department and system on the boat from engineering, deck seamanship, gunnery, operations, damage control, communications etc. A pretty common one was Z-29-G, an exercise to engage a floating enemy mine with gunfire. Many 55 gallon drums were shredded as a result. Another was Z-10-CC, surface tracking of contacts by radar. We did precision anchoring, towing a “disabled” boat, man overboard, engineering casualty drills, fire and flooding drills, medical response, navigation and piloting, and many others. Small boat, small, well-trained crew, good fun. Everyone knew everyone else’s job pretty thoroughly.

Below is a shot of PTF-17 “coming at ya”. Photo: Curt Froyen

Patrol Gunboats:
As stated earlier, the Patrol Gunboats USS Asheville (PG-84), USS Crockett (PG-88) and USS Marathon (PG-89) joined CRD21 sometime well after we were commissioned. These guys had seen a lot in combat in Vietnam before they were redeployed elsewhere in WestPac. They were assigned to CRD21 and for awhile, lived with us. They were tied up at our usual berths on the south side of the north quaywall as shown in the photo below.  (They were never moored on the other side of that quaywall as another blogger had posted – the water was very shallow there).  The PTF’s were moved to the south quaywall. The PG’s needed the steam lines for moored heating which we didn’t and the water was deeper there as well.  The south quaywall was not good for the PTF’s.  A strong storm surge often built up in the harbor right there and the PTF’s were sometimes damaged against the fenders and pier.

In the winter (1974-75 I recall) when we were pulled for overhaul, they tried to stay at Great Lakes but there was a problem. Since they remained afloat and the harbor would freeze hard-over, their hulls needed protection. So a system of weighted, perforated firehoses was installed by our SEALS on the bottom under their keels and filled with compressed air to generate a constant stream of bubbles. This pulled warmer water (OK, it was cold, but still liquid!) up from the bottom, theoretically keeping the ice away from their hulls. They couldn’t turn over their engines/shafts periodically to keep things straight and loose and despite the fact that they had controllable-pitch screws there was fear they would churn up the hoses. (They could rotate at “zero pitch”, not causing thrust but rotating nonetheless.) Worked. Sorta.

But not really, so they were sent down to the Chicago Naval Pier for a similar system that was better supported. I understand that was a real problem between the City of Chicago and Navy Public Works at the naval facility down there, but somehow that’s where they remained. These ships were real thoroughbreds and they needed a lot of TLC to remain operational. With their diesel engines for 0-15 knots and a marine gas turbine for above 15 knots, they were a hybrid design with many complexities.

I only remember operating with them one time before I left active duty in August 75 and that was some simple surface tracking and “Div Ops”, no gunnery. They seemed to be down for maintenance a lot and their active crews were reduced with the idea that the Reservists filled out the WQS Bill. Fine in theory but all that maintenance had to be done when the Reservists were generally not aboard. I only have a few photo’s of them, here’s one of the USS Asheville nested-out from one of the others. Can anyone else add to this story? Photo: Tim Sammons

Fun “Fact”: The day Crockett and Asheville arrived, the Navy Band had mustered on the pier, everyone was there but there was a thick fog bank off the coast and visibility was about 100 feet. They had anchored-out for the night waiting for the fog to clear for their 0800 arrival. One of the PTF’s got underway to “investigate”. Since we were supposed to be “competitive” with them for some reason, someone thought it be appropriate to greet them and show them how things worked around here. The Sea Story goes that PTF-X made a radar-controlled close pass down their starboard sides at 30 knots, pulling a water skier decked out in an orange kapok life jacket and M1 Helmet – on a 200 foot rope.  Outta the fog – zoom by – disappeared into the fog. PT boat? What PT boat? Water Ski’s??

The NAVBASE had rules about uniforms that unfortunately applied to CRD21 as well. The enlisted wore dungarees and the officers and chiefs wore khaki’s, not the green utilities worn by the rest of the Navy’s CRD units. That also applied to the SEALS who much preferred their UDT shorts, blue & golds and boots. A source of much grumbling but as they told me: “You wear-a the name, you play-a the game”. Incidentally, if you see any photo’s of PTF’s with the crew in Greens, it was not CRD21, if they were in dungarees, they most likely were CRD21.

Our SEALS’ principal involvement was to train, assist and advise us on the CRD and PTF’s primary function of transporting, inserting, supporting and extracting SEALS on any number of types of missions. I won’t say much about this except to say it was done mostly at night, hence few photo’s. Those evolutions were often to move into a target area, launch them in their IBS (Inflatable Boat Small – Navy lingo) and then stand by to support them with gunfire if necessary. Then move in, pick them up, leave rapidly and discourage anyone from following us.

Here’s a photo of the IBS with its small outboard motor which was used in situations where the PTF didn’t get too close inshore for a variety of reasons. These boats were ideally suited for the SEALS missions.  Normally crewed by 3 men paddling on each side plus a coxswain in the rear.  Hence the origin of a 7 man SEAL squad.

Here’s a shot of the crew training for a night IBS launch. The lifelines and stanchions were dropped and the boat readied for launch. Seems simple enough on a calm day but required good crew coordination at night.  Photo: Tim Sammons

One notable evolution, not involving the PTF’s was a SEAL training Op on the Mississippi River, nominally as a SERE (Survival, Evasion, Resistance, Escape) class. I got to go along as a “trainee/observer” which I thought was great fun and a greater experience. The “mission” was to infiltrate the AO, capture some enemy canoes at a location on the Turkey River in Iowa, paddle downstream out into the Mississippi and then go upstream for about 10 miles to Lock and Dam # 10 to simulate sabotaging it. We were only allowed to carry a jungle hammock, knife, fish hooks and line, “living off the land”.  No cameras allowed, no photo’s. We hid out on islands and along the banks of the river by day “scavenging” for food.

This was Iowa farm country….Corn on the cob, potatoes, apples, watercress, creek chubs, blue berries, strawberries, catfish, an unfortunate rattle snake (they DO taste like chicken) and even some watermelon left by boaters. We built an in-ground meat/fish smoker to preserve the meat for storage and transport – worked great. Lee knew the territory and what to eat, I gained 5 pounds during the 14 day “survival” trip…

We also learned to “cut enemy lines of communications”, capture vital enemy communications equipment and generally doing what SEALS did. It ended with some rappelling training (I watched) on some big cliffs along the Mississippi. (Hint: Don’t rappell while wearing a Woolly-Pully”.) Then off to the “Cave” safe house to meet the local partisans and debrief. If you were there, you know what all of this actually means…..  Good training, good fun.

To maintain their “Jump, Dive and Demo” proficiency pay they came up with many novel training evolutions.  In the diving arena they would infiltrate into the local golf course at night (dead of winter-no one around), cut a hole in the ice over the various water hazards and scuba dive for the treasure trove of golf balls therein.  They would also go out to Fox Lake in northern Illinios, the scene of winter-time motorcycle and snow mobile races on the (more-or-less) frozen lake.  They retrieved many snowmobiles or dirt bikes that managed to submerge after penetrating the ice.  They would also dive along the many fishing piers along the lake shore at night, pulling buckets full of fishing lures that had gotten snagged on the pilings.  Good practice for planting Limpet mines on that enemy warship.

The Command also sent them to Outboard Motor School in Waukegan (home of Johnson/Evinrude Outboards), off to lock picking school, diesel locomotive (sabotage) school with the Illinois Railroad and other interesting locales.  They also did parachute jumps and demolition refresher training with an Army Special Forces unit based at Fort Sheridan, near Chicago.

One of our SEALS, Petty Officer “Lenny”, would often lay down on a quay wall with his arm submerged in the water – for an hour or more at times.  Then – whoosh!  Out would come a big Coho salmon he caught by the gills with his bare hand….I tried it – just ended up with wrinkled fingers….”you had to communicate with the fish’s environment and gain his confidence properly…”

It turns out that this manner of fishing had many lessons. The Objective was simple: Grilled salmon for dinner. For a successful tactical mission you had to get inside the fish’s OODA Loop (Observe, Orient, Decide, Act). You would use all the military arts of observation, recon, stealth, patience, timing, surprise and quick action to accomplish the mission “at hand”, and do it faster than the target could get inside YOUR OODA Loop. Another day in the life of Freddie the Frogman…and a young Ensign.

One day, the Naval Training Center commander asked CRD21 to put on a “combat display”, probably for Family Day or other open house on the base.  So we concocted a mission along the waterfront where the RV park is currently located – in those days it was open beach / scrub.  NTC had set up some bleachers along the coastal road so visitors could watch.

The idea of this simulated night Op was a PTF would sneak in, heave to and launch the SEALS in the IBS who then paddled ashore.  There they planted some demolition on the “target” (an enemy missile launcher as I recall) and then withdrew.  Somehow the enemy found out before they blew the demo (half pound blocks of Composition B explosives)  so the PTF had to return fire as the SEALS paddled back out to the boat.  As part of the preparations for the “demo” (ahem), they planted many small blocks of Comp B around the beach to simulate our incoming mortar and 40 mm gunfire.  Cool.

So then they blew the main demo charge (electrically fired by a SEAL actually on the beach with the safety officer) and BOOM!  big explosion throwing up lots of sand then lots of smaller explosions simulating our mortar fire.   BOOM  BOOM  BABOOM BABOOM etc.  Lots of dust and flying shrubbery.   We were firing the .50 cal machine gun with blanks.  Enemy missile launcher destroyed,  all hands recovered, PTF roars off, the crowd cheered.

Fun Fact: Later,  we got the “bill” for all the broken windows in the Fire Controlman Training Building up on top of the bluff.  OOPS!  Amazing what the shock wave caused by a few pounds of explosives can do, even at a distance.

If you read GMCM Bob Stoner’s account of life at CRD21 (highly recommended) he will tell of a certain Gunners Mate who incorrectly installed the Blank Firing Adapter on our .50 Cal machine gun.  Modified of course with the air-cooled aircraft barrels required for blank firing of an M2 .50 Cal. back in those days.  That BFA probably went sailing over the spectators heads, no one was the wiser except the .50 gunner who now had an unexplained stoppage.   It’s probably still buried in the bluff below FT “A” School.  Another day at the office….

These guys were the “Old Navy” SEALS when the Teams were much smaller and tighter as compared with today’s large NSW community, so I’m told.  They had done everything imaginable during the war, didn’t talk about it much but you knew they knew their business. I learned a lot from all of them and Lt “Lee” was a great mentor of mine.

From the GRC-109 manual: Just makes you want to be there!

Listen in !

AR

Designed as an “Armyfied” version of the CIA’s previous RS-1 radio set which had been in widespread use in the 1950′s.  They are very similar in appearance and operation.  The Army adopted it (circa 1962) with minor modifications as the AN/GRC-109 to be supportable with standardized training, repair parts and depot maintenance within the Army supply  and logistics system.

With a transmitter output of around 10 watts, a built in key that works well, versatile power supply and a sensitive receiver, they did the job.  In approximately 1969 the Army introduced the AN/GRC-109A, basically the same radio system however the A model had substantially thicker and stronger cases and it included a quick-remove cover with snap closures versus the screw-down types of the basic 109.  The 109A also included the connector for the GRA-71 burst keyer; apparently most or all of the previous 109′s were subsequently modified for this as well.

Below is the CIA’s RT-3, the transmitter of the RS-1 system. Almost identical to the GRC-109 transmitter (T-784/GRC-109 as described above) but note the absence of the connector for the GRA-71 Code Burst Keyer and a different arrangement of the CW key and receive antenna connector posts.  No other “US” markings – I bet that fooled ‘em !

RT-3 Transmitter from RS-1 System

Reference (3) describes the use of the GRC-109 by US Army Special Forces in Vietnam. It states that the GRC-109 apparently was not issued to conventional Line units in that era.  Other references state otherwise.   In those days, typical Line units depended upon easy-to-operate voice radio systems they had available, especially as the CW skills of many RTO’s atrophied along the way. The 109′s were deployed at SF camps and in fortified villages throughout the country as the only means of reliable comms back to HQ in Saigon and between themselves for mutual support.

The GRC-109 / RS-1 was also used by Special Forces world-wide in the 1950′s – 60′s and likely beyond. I have seen a BA-48 battery (also used with the GRC-9) with a date code of May, 1984 although it’s possible it was made under a foreign sales contract to support these radios being used by our allies. – Or not -

Apparently they were reliable and quite successful in the Special Forces networks in Vietnam. Due to their simplicity and all-weather ruggedness, I would assume they were more reliable than the FRC-93 (Collins KWM-2) that SF was beginning to deploy at SF camps.  Especially when you consider that the FRC-93 required AC power and associated generator not to mention the serious environmental protection.  The GRC-109 could use AC or the hand cranked generator thus increasing its dependability in a combat environment.  They were installed in the “commo bunkers” as a basic means of protection and operational security, however when under attack the VC and NVA were good at spotting antennas. The reference states that as a countermeasure the wire antennas were put inside bamboo “pipes” and buried 18 inches underground – and were still effective in communicating. It’s an authoritative reference but I will take it for face value, no mention of freq or operating range was noted. That’s an experiment I will try to duplicate this summer and see for myself. I’m a bit skeptical, especially during the “wet” season there. I have made contacts with mine using only a 1/4 wave wire laying on the ground – that works OK – but that’s a different story.

My GRC-109 field kit below:

Powered by 70-270 VAC, an optional UGP-12 gas fueled generator, 6 VDC from that captured Zil truck battery or a G-43 hand cranked generator, they could be used anywhere.  The receiver could also be powered by itself from a BA-48 battery for those long watches on the Alert Net.  Environmentally tough, they can withstand and operate in lousy weather.  Plugged into an electric lamp socket in that hotel “safe house” via a screw-in adapter, their CW would not  even blink the house lights during those 0242 hours  SITREP transmissions back to base.  It is capable of running the receiver with crystal control – that works very well but the variable tuning works better for casual Ham operation.  The TX of  course is crystal controlled.  Shown below running a coax-fed dipole for TX and a random RX wire launched into a nearby tree with a pine cone for a weight.

GRC-109 Operations in the Mountains - N6CC

Below is a station on the granite, up in the Sierras, tracking and reporting suspicious canoeing activity on Caples Lake in the background.  The off-camera PU-181 rattling away generating AC power and also discouraging mosquitoes.  A great campsite radio when you are well beyond cell-phone or repeater coverage.  You can also use it to get the latest soccer scores from Radio Australia, coordinate your operations with a time-tick from WWV or get a good laugh from Radio Havana Cuba, “Free Territory of the America’s” on the shortwave bands.

The transmitter will load anything, much like the RS-6.  I have powered up dipoles, inverted “L”s,  random wires, a barbed wire fence, the rain gutters on the home QTH (stealth ops) etc.  As seen in these photos, the T-748/GRC-109 included a TX panel connector for a GRA-71 300 WPM burst keyer so you could send your SITREP with a lower probability of detection before you QRT’d and boogied.

The below photo is another favorite campsite further up into the mountains.  Set up next to my cot, it kept me in touch from a place not covered by VHF FM repeaters and probably 40 miles from the nearest cell phone coverage area. My buddies just shake their heads – but then ask me how to go about getting a Ham license….

BTW, that “hot pink” object in the background is an Army Signal Corps VS-17 visual signal panel laying on the rocks.  They are used to mark friendly positions when working with Tactical Air or other friendlies in the area.  We were using it so that late arriving campers to the general area could locate our position exactly from their avenue of approach.  You can see these things in the bush from many miles away although this photo doesn’t seem to capture its brightness. It must be stressing the color filters in my cheap digital camera!

In fact, it caught the attention of an F-5E Tiger II  jet pilot flying out of NAS Fallon Nevada.  He went overhead about 10,000 feet above us; it caught his eye so he banked and took a second look.  He knew something “military” was going on – civilians don’t usually pack and display these panels; he knew exactly what it was.   He made a wide, descending  turn and then roared directly overhead about 500 feet above us in a hard bank, standing on his wing to see what was going on.   We waved.  His F-5E was painted with Soviet camouflage markings and Red Stars – he was part of the “aggressor” training squadron at the Navy’s Top Gun school off to our east.

My buddies were bragging about how many fish they caught (I didn’t catch any as usual) but I caught an F-5E with MY lure !!

Come to think of it, I was running the GRC-109 at the time.  Maybe the J-STARS aircraft controlling the fight from a hundred miles away detected my CW signal and then got an HF DF fix on my position.  Maybe it wasn’t the panel……

So we then waited for the “duty”  C-130 to parachute us a pallet of MRE’s, water, batteries and ammo but nothing showed up. Well, an airstrike didn’t show up either so I guess we called it a draw.

GRC-109 in the High Sierras

The only apparent operational shortfall of the GRC-109 while used on Recon patrols was their weight, assisted by the heavy GN-58 or G-43 generator (the transmitter and receivers are relatively light).  Although substantially smaller, lighter and easier to pack than its predecessor GRC-9, it was still a bit heavy even though it was probably viewed as the latest state-of-the-art portable radio station at that time.  It would have been interesting to parachute with one of these strapped on (especially with the G-43 generator and seat) but that was apparently routinely done.  They were ultimately replaced by the PRC-74 or PRC-64 depending upon the unit/AOR, but their use continued on throughout the US military.  Clearly, they were heavily utilized by the CIA along with its predecessor, the RS-1.  One reference stated that they were routinely secreted inside the walls of selected apartment buildings in eastern Europe for use by stay-behind personnel in case the neighborhood went further downhill.

GRC-109 Suitcase Clandestine - N6CC

The above photo shows my veteran GRC-109 as it might have been stashed under the floor boards in the attic of Der Funkspiel Hotel, on the corner of Lenin Street and Karl Marx Way in Budapest. This was just across the street from the Headquarters of the Soviet “Friends” T-54 Tank Regiment. Circa 1956. The brave Hungarians eventually won THAT battle.

Willing to bet there are many still in eastern Europe, southeast Asia or buried in various other interesting places worldwide.  Someone back at “HQ” still maintains the freqs/times/callsigns/one-time pads and Comm plan in case any of these sets are ever retrieved and activated by OPLAN XYZ.  Hope someone still knows morse code!  All the best agents do, of course…..I have no doubt that these covert rigs will fire right up when needed.

Below is my trusty ’109 operating “tailgate portable”.  That big box of crystals sure makes life easier on the Ham Bands…  This particular setup runs the “small” AC power supply, PP-2685/GRC-109 which is powered by a 300 watt 120 VAC sine-wave inverter installed in the Bronco.  Clean, quite power.  The larger PP-2684 does everything the 2685 does but it can also be powered by a 6 VDC battery; it can also charge that battery.  For field ops requiring light transport, neither AC power supply is used.  In that configuration the GN-58 or G-43 hand cranked generator in conjunction with the CN-690/GRC-109 is used between the TX/RX and the generator.  The CN-690 contains an OB2 VR tube to regulate the RX B+ voltage – and is much lighter and smaller.  The receiver can also be directly powered by a BA-48 battery.

GRC-109 DC-DC Converter powering receiver - N6CC

Above is a R-1004/GRC-109 Receiver being powered from a 12 Volt Gel Cell via a DC-DC Converter which solves the “continuous receive” power requirement when in the field. Details on the Converter are in the Design and Engineering post elsewhere on this website.

My set came from Fair Radio. It has obviously seen a lot of operational service, its pretty scuffed up but being indestructible, keeps on going. None of the serial numbers match but some of the units have an interesting pale green lightning bolt stenciled on them. Wonder who that was….One strange problem they have is the receiver is starved for antenna signal when the antenna is routed through the transmitter during “key up”. The key contacts short out the receiver signal to avoid overloading on transmit, but there is something lacking in the design – the only problem I have found. I guess the TX output network loads the antenna circuit too much during key-up. I’ll have to investigate. As a result, I usually run mine with a dipole or inverted L on the transmitter and a random 50 ‘ wire connected directly to the receiver. Works great but takes a little more setup time. The RS-6 set does not have this problem, but it uses a T/R relay to isolate things, the ’109 does not have a relay.

The “GRC-109 A” model uses the “hasp” method for connecting the cast aluminum covers to the radio chassis. Very strong but very heavy and it makes each chassis quite a bit bigger – I prefer the thumbscrew hold-downs of my plain ’109 better. They also fit inside an ALICE pack better.

A few “features” are noted.  The transmitter antenna output tuning indicator is a #47 lamp across a 20 ohm resistor, this in series with the output to the antenna connector.  This is really an RF current monitor since it is in series.  With antennas with high impedance input, there is little if any glow from this lamp although RF power is being delivered to the antenna.  A 1/2 wavelength (or integer multiple) wire is an example – it may seem like you can’t tune it.  To solve this, I carry an NE-51 neon lamp with leads soldered to it; I then place this from the antenna connector to ground, thus serving as an RF voltage monitor since the transmitter is developing a high voltage in this situation.  This will glow brightly with the above antenna since the input to a 1/2 wave wire is high impedance.  I also use this trick on my SCR-284 transmitter as well.  Handy.  With low impedance antennas (like a dipole or a 1/4 wave wire) the installed #47 glows brightly when tuned.

In the receive department, the R-1004 does not have a AVC/AGC circuit so you may have to ride the “Gain” control in the presence of strong signals.  I have not found this to be a problem when operating up in the mountains – few really strong signals to contend with (no locals !).  However, the set does not incorporate a means to generate a sidetone signal so you can’t hear your own keying very effectively.  Since the receiver does not effectively “mute” during key-down (the receiver antenna terminal is grounded via the CW key when using a common antenna), you can hear your own signal but it seriously overloads the receiver.  Then, you must turn the Gain control all the way to minimum to produce a usable sidetone.  A bit of an annoyance if you are used to having KenYaeIc appliances do all the fun stuff for you.  In typical military comms applications you would likely be transmitting on Freq X while receiving on Freq Y, therefore loosing the ability to monitor your own signal.  Takes some getting used to – just “feeling” your fist via the key.

Comm Center, Forward Operating Base (FOB) “PIGOUT”
Above is the basic field setup with the TX and RX powered by the “small” PP-2685 AC power supply and a gas-driven generator, the G-43 standing by.  TM 11-5820-474-14 (18MAY1962) indicates the use of the G-43 hand cranked generator. However the G-43 is functionally interchangeable with the GN-58 and I am not sure when the change from the ’58 to the ’43 occurred. Still looking for a reference on the GN-58 configuration. We were running a coax-fed 40 meter dipole up about 15 feet with a separate 64 foot wire for the receiver. Folding stool and big crystal collection optional while on operational missions.

Ditty-Bopping in the Mountains. An effective, reliable radio.

Field Ops with the AN/GRC-109

Above is the same system in action, as used to work WA6OPE on 7050 KC at 2000Z, a 120 mile shot, human powered. Good daytime signals with GRC-109 sets on BOTH ENDS of the contact.  Here we were running the set with the G-43 hand cranked generator and CN-690 Voltage Regulator module to power both the transmitter and receiver.  A pretty good workout (I’m told)!  Without a BA-48 battery just to power the receiver, the hand cranks must obviously be going for both transmit and receive – not recommended for casual operating…  So we compromised later on – ran the receiver off the PP-2685 on AC power for continuous tuning and the G-43 genny to power the TX only on this Op.  Cheating, but effective and easier on the non-Ham power source (who would rather be fishing…).

I had sent the above photo to Ray at Electric Radio Magazine for consideration in the “Electric Radio In Uniform” department.  I guess he liked it, he ran it in the Nov 2011 issue.  I guess he REALLY likes it – he ran it again (by mistake) in the April 2012 edition.  I guess some hams resonated with it – I have gotten some nice feedback on the ’109 in the woods operations.

Below is the ’109 at work in a different camp sending out the daily Fishing Report (got skunked AGAIN).  I was running it off the PU-181 generator (120VAC) at the time..  That generator is well suppressed – unlike my reliable but ignition-noise plagued Honda EX1000.  More on THAT piece of hardware later… The audio output of the GRC-109 receiver is 4000 ohms so an old pair of Hi-Z headphones with tip jacks works great.  I don’t have the issued-headphones just yet.  I often run it with a simple “amplified speaker” as seen here.  It’s from Radio Shack (horrors!) and is just a simple amp using a 486 amplifier IC driving a small speaker, the small white box seen here.  Works great when you don’t want to wear headphones.  Like public demo’s….

Also, I like the built in key but I usually use the J-45 “leg iron” key as shown here – more comfortable for long CW sessions.  It appears that I was using separate wires for TX and RX.  After many years of working HF CW, I have found that almost any piece of wire you can get up in the air will work well, producing many contacts.  Dipoles have the highest performance/complexity ratio and are my usual favorites in the bush.  A pair of dipoles on 80/40, fed by a common coax works extremely well and is simple to get up.

My camping buddies always prefer to arrive at the LZ a little late – helps them avoid big dents in their vehicles while I am slinging 8 ounce fishing weights up over the trees. A source of great amusement for them but I have found nothing better than that simple expedient. Easy work to put a dipole up to 100 feet high, but usually much lower. I’ve become a pretty good shot with these. I use the anchor line sold for duck decoys as the antenna halyards. Lightweight, strong, stealthy. Better than 550 parachute shroud line which is harder to launch and much more visible.  Wear gloves!

Again, much info on the Web regarding these radios so I will continue to focus on my experience with my set and its use in the field.

Above: The GRC-109 in camp for Vintage Field Day.

Below is another shot of the GRC-109, this time paired with my Command Set operating on another Vintage Field Day from another riverside campsite. Fun radios.

AR

I have had this one since I bought it in 1964.  It works quite well and has seen several field ops at various campsites.  It was NOS when I bought it.

Below: It is set up at a Stanislaus River campsite as my “night stand” so I can talk to the West Coast Military Radio Collectors net on 3985 KC on Saturday nights after I hit the rack (in the foreground).  I am still collecting the correct parts so that is a TBX key and an ersatz speaker.  I was running it from the PE-103 / PE-104 powered by a 12 volt deep cycle battery.  Looks like I had moved the dipole coax to a different radio.  It’s a pretty good “woods” radio and is very sensitive especially in a radio-quiet environment like this.  Sounds great.  That’s an NE-51 lamp wired across the antenna connector so I can tune up the transmitter in the dark – the RF meter is not illuminated and the radium/phosphor dial paint has long since faded out.

SCR-284 set up at my "night stand" on the river - N6CC

Here is another setup at a different camp. That whip mount fits the radio and MS – mast section perfectly but it is obviously different than the brown plastic mount usually seen. It is the originally supplied IN-106, a heavy, fragile part. These were quickly replaced by the plastic IN-106A insulator which was much lighter and less fragile for field use.

Like most of my WWII radios (all?) this one still contains all but one of the original tubes. I did replace a few capacitors and they are difficult to access in the receiver. The most critical one was the AVC time-constant capacitor. In that high impedance circuit a leaky capacitor can cause all kinds of gremlins to appear. Change it out.

Radioactivity: Incidentally, the meter in my SCR-284 is relatively “hot” radioactivity-wise. More so than any other radio or meter I have. Probably because there is a relatively large amount of paint on the scale.  It puts out about 6 mR/hour as measured with an Eberline E-120 Geiger counter (with detector probe HP-190A) contacting the meter glass. Radium 226 is an Alpha emitter and it stays hot for a long time (half life of 1620 years as it decays into Radon gas). It finally damaged the phosphor paint it was intended to excite in this meter. Very, very dim glow these days. Don’t disassemble it…This is most likely Gamma radiation – Alpha’s won’t penetrate the meter glass, nor will most Beta’s.  My R-390A Receiver meters also had detectable levels of radiation:  The Carrier Level meter read 1.2 mR/Hr, the Line meter read 0.4 mR/Hr.  Background during tests was 0.01 mR/Hr.  My TBY meter read 1 mR/Hr, my GRC-9′s labeling each read just background.  Probably no radium paint used on mine.

Below, a couple of shots of the SCR-284 “in the field”. Merrills Marauders, 1944. Photos by Bernard Hoffman. Dim watermarks indicate these photo’s appeared in Life Magazine.

This first photo shows the whip antenna not installed in the IN-106 insulator. Likely they were using a wire, probably an inverted “L” depending upon their tactical situation and availability of local supports. Some wires are draped over the insulator leading off into the bush. Note the absence of weapons except for the likely K-Bar knife worn by the helmeted soldier. Also, there appears to be a PE-104 vibrator power supply under his right arm – this powers the SCR-284 receiver when using the hand-cranked generator.  Without it, you need to have a BA-43 battery – which is preferred. Nice – if you can get one in Burma that still has any charge left in it. Foliage looks like bamboo, probably in-theatre, Burma.

In the below photo, the radio switches indicate it is on the Low Power, Voice mode. The T-17 microphone is lying on the operating table. In this case they appear to be using the whip antenna as the lead-in wire seems to be connected. But I don’t see the ground wire for the counterpoise. Maybe not always needed, a hassle to rig. This might be a company CP, working with SRC-536′s or up to another SCR-284 at Battalion level. Merrills Marauders were usually resupplied by air; the photo may be depicting them coordinating an airdrop on their position

Note the object behind the GN-45 generator in the above photo: Looks like a saddle from one of the “Motor Transport” units grazing nearby…Much better than humping this gear! .

SCR-284 at Batt Com Center N6CC

SCR-284 at work: Normandy

Above: Calling in Naval Gunfire with an SCR-284 from a shell hole in Normandy. The soldier on the right is likely taking tactical calls-for-fires on his SCR-536, relaying from a nearby infantry unit. Official US Army Photo

Later on……”With voice transmissions ruled out by distances, communications specialists must rely on continuous wave radio operation, using the International Morse Code.  They must be able to receive and transmit at the rate of 18 words per minute, perform maintenance up to Third Echelon and even build a working set out of parts at hand.  Other team members must be able to work at least five words per minute and know how to set up and operate a radio.  Workhorse of the Special Forces is still the dependable Angry Nine, officially the AN/GRC-9.” Special Warfare U.S. Army, Chief of Information, U.S. Army 1962.

Below is my “GRC-9″ set up on the Pacific beach at Spooner Cove near San Luis Obispo CA during less stressful times.  (Actually, it is a GRC-87 – do you know the difference?) We were running “Coastwatcher Ops” and transmitting Bikini Reports back to a TCS set at Camp San Luis Obispo acting as Net Control.  This was during the Military Radio Collectors Group meeting in May 2010.

AN/GRC-87 on the Beach. N6CC

The distance from here to KG6UTS at Camp SLO NECOS was 9.2 Miles over hilly, rocky terrain.  From here to N6IHU was 3.3  miles and N6IHU to Camp SLO was 5.8 miles.   N6IHU was running another GRC-9 in a portable configuration however he was using the DY-88 Dynamotor power supply.  Under the conditions at that time (appx 1000 hours local) the signal to noise ratio of received signals was 2 to 3 times better on the whip than the AT-101 wire which surprised us.  It was running approximately northwest, broadside to Camp SLO, averaging about 6 feet off the sand.  Comms with the 15′ whip antenna were Q5.  I didn’t note the FoF2 critical freq at that time to see if the low wire would work in NVIS mode under those conditions.  Apparently it was lower than our 3885 freq and/or the D Layer absorbtion was very high then.  We ran the standard ground counterpoise, G-43 hand cranked generator and a battery for the receiver to save the “power supply”.  The TCS was running a 30 foot inverted L and N6IHU was running the standard whip antenna.  This setup would have been a very workable tactical circuit. Photo: Tim Sammons

Coastwatcher Ops Pacific: GRC-87 N6CC

Below is a typical mountain top campsite to cover all circuits. There is the GRC-109, GRC-9, PRC-47 and the mobile GRC-9 all on-line. However, looks like the flash caught the Midwatch off guard. Zzzzzzzz.  Good thing the Sergeant wasn’t around!

Below is a shot of our Perimeter Defense Force checking out the Company Command Post.  Note the GRC-9 AC Power Supply built in the .50 Cal Ammo Box on the ground.  Provides all voltages from 120 VAC.

QSL Card; USS Pampanito SS-383 NJ6VT

Above: QSL Card from the USS Pampanito SS-383, moored in San Francisco near the Golden Gate bridge. I worked their ham station, NJ6VT aboard the sub on CW with my GRC-9 from our Forward Operating Base in the Sierra Nevada mountains. Her wartime Navy call sign was NJVT.

Below is another shot of the GRC-9 in the field using the 50 caliber AC power supply. “You have a strange rushing sound in your Transmit audio”….Yup….

Below is another shot while sending Ditties from FOB (Forward Operating Base) Margarita….The little AC power supply in the .50 Cal ammo can makes it convenient to work in camp. Especially when you bring the generator to run the Blender anyway!
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Would you believe a solar-powered GRC-9? Been there, done that. Here we are set up in the mountains west of Lake Tahoe at OP COMMANDO, monitoring kayak traffic 2000 feet below us on the North Fork of the American River. Panel charged the deep cycle battery which powered the sine wave inverter that powered the ammo box power supply which powered the GRC-9. Inefficient as hell but it worked!

Here’s another shot of that position – we also had a PRC-47  going on CW and LSB as well. There is the wreckage of a C-46 Commando somewhere within a mile of this location.  Very dense forest in here.  It’s on our list for a search expedition. This spot will make for a very good base camp.

Below is the GRC-9 at work down in the Commo Bunker sending out the nightly SITREP at Zero Dark Thirty

GRC-9 at work in the Commo Bunker

My replica radio will operate with B+ as low as 24 volts but I usually run it at 63 VDC provided by seven, 9 V batteries.  They simulate my 67.5 V dry cell that has failed long ago. The POW camp captives made batteries from bits of copper and zinc uniform buttons and battery acid captured from enemy vehicle batteries.  Reference (12).

Here’s a look at the innards.  The bamboo coil form is evident,the winding job is embarrassing.

The Signal Corps of WWII had many men who were “Ham” radio operators before the war and the design of this type of radio would have been memorized long before – it was a basic, common design. No instructions needed by skilled personnel.  The radio was built by Capt. Russell J. Hutchinson, US Army Engineer Corps and subsequently passed to William D Gibson, a Ham radio operator and Signal Corps Lieutenant.

This replica is made from primarily WWII vintage electronic parts and includes 2 tuning coils wound on 1 inch diameter bamboo forms.  One is for SW broadcasts, the other for broadcast band use; the turns are held in place with pine pitch.  The four D cell filament batteries are appropriately concealed inside a piece of bamboo tube.  (Mine uses a 6SK7 because I couldn’t fit 8 D Cells inside the bamboo tube to power the 12 volt filaments of a 12SK7.)  It is my first attempt at building a one-tube regenerative receiver and it works pretty well on AM and CW.  SSB reception (these days) is dependent upon careful adjustment and your imagination – SSB stability isn’t great but theirs brought in the AM news from BBC, Radio Australia and US west coast stations including KGEI in San Francisco.  Much more fun to play with than a “software defined radio”.  Theirs was a courage and ingenuity – defined radio.

So, does it really work? Yes, surprisingly well on AM shortwave. Like all Regens, careful adjustment of the Regeneration control is important and all the controls interact with each other to a certain extent. The Regen control varies the screen voltage and therefore the gain. The tuned circuit is isolated from the antenna by a series variable “antenna” capacitor which reduced the detuning effect of the antenna on the tuned circuit. If the wind is blowing the antenna around, the circuit detunes a bit and you have to compensate, but that is a minor problem. Selectivity is good, “tuning rate” via the screwdriver-trimmer is very fast but the Chicken Head fine tuning knob makes that acceptable. Moving the feedback tap on the tuning coil makes it ” a completely different radio”, something that can only be appreciated while experimenting with the construction and testing.

I can clearly hear WWV on 5 and 10 MC and occasionally CHU in Ottawa on 7850 KC. The big international SW stations come in pretty well. Considering the primitive nature of this radio, it does the job of providing outside contact as your imagination drifts back to the Philippines in WWII.  The challenge was to see what kind of performance could be squeezed from some junk-box parts. Very satisfying project and a big hit with the public at displays and demonstrations.

There is speculation that the radio was actually originally built on Corregidor before its capture (Bataan death march to Cabanatuan) but was later modified in the camp for a 6J7 tube after the original 12SK7 tube burned out.  Considering the parts requirements, this scenario rings true to me. It hung on the bunk of its custodian, in its canteen cup within the canvas cover – hidden in plain sight.  The headphone(s) would have been hidden elsewhere.  Its discovery would certainly have resulted in the summary murder of that American soldier, at a minimum.

Reference (11) notes that there was a second shortwave radio at Cabanatuan, built by prisoners with parts stolen from the enemy radio repair shop where some US personnel worked.  They would capture the necessary parts from enemy radio equipment they were supposed to be repairing, telling their captors that parts had failed and replacement parts were needed.  This radio was powered by the camp electrical lighting system which the prisoners had occasional access to. Brave, resourceful people.

As a telling fact, the United States GAVE radios to POW’s, at least to the Germans interred in the US.  We were not afraid of them finding out what was going on. The Escape Factory, Reference (6).

Also, see Ray (VK2GRP)’s excellent website for a representative schematic and his fine reproduction radio as well (his pre-dates mine).  Well done Ray !  www.tuberadio.com