Military Radio “Field Day” 2019

Military Radio Field Day 2019 After Action Report

Another field exercise was conducted by the West Coast Military Radio Collectors Group (Detachment Alpha, FWD). The overall objective of this FTX was to operate, exercise and evaluate various military field and pack sets on HF/VHF frequencies. And Eat.

We deployed to a very remote location up in the Sierra Nevada mountains about 70 km north of Yosemite National Park. Due to scheduling issues this was the weekend following the ARRL Field Day 2019. Same idea, less contest bedlam!

Radio sets included: AN/TRC-77 (2), AN/TRC-88, AN/PRC-74B, PRC-174S, AN/GRC-9, ME-61. Also along was a PRC-127ef, AN/PRC-25, RT-70/VRC-7, AN/GRA-6 Radio Wire Integration system, AKA “Net Radio Interface”.

The GRC-109 stayed home this time. We went with CW AND SSB/AM.

AN/TRC-88 HF SSB/CW Transceiver

Part of the 4 day, WAY off-grid trip was to build, launch and evaluate several HF dipoles, wires and an Inverted L for 80, 60 and 40 meters. They were rigged low and horizontally to enable Near Vertical Incidence Skywave comms with our remote buddies as frequencies and times required.

Below – Setting up one of the operating positions in a quiet forest clearing.
Forward Operating Base (FOB) PIG CHIPS:

ARRL Field Day 2019 Military Station Ops

With the great WX at 5010 feet AMSL, everything remained outside the tents/hootches.
WWV and the little alarm clock are essential for making our pre-planned Comm Windows with HQ and buddies. Too many distractions in camp!

Here is the rare TRC-88 on Upper Sideband and the CW TRC-77 awaiting its turn for the antenna. AN/TRC-88

AN/TRC-88 and AN/TRC-77 standing by for the shared antenna

The TRC-88 was powered by a small 12 volt Garden Tractor battery. The TRC-77 was operating from its usual 12V, 16 AH Gel Cell pair in its DIY battery box. That box and battery set fits either radios as needed. I need to make another one.

The AN/PRC-74B also came along on this trip to evaluate its present status: Otherwise operational but with a dead RF power amplifier stage in the transmitter. The PA module is in the repair/redesign queue for now. AN/PRC-74B

Evaluating the PRC-74 receiver in the forest

I wanted to try out the receiver section of the radio using both an AT-271 whip and a resonant dipole. I don’t have the proper center-loaded AS-1887A/PRC-74 HF whip for the set so I was just using a standard 3 meter collapsible whip. It received well. MANY thanks to Mark, K1HF for providing the NIB battery box and whip antenna mount for this set.

The PRC-25 was online for local comms back to the RT-70/VRC-7 mounted in the Bronco. We also had the GRA-6 Radio Wire Integration (RWI) set connected to the VRC-7 for ongoing remote control experiments. (Last year’s RWI tests with the PRC-47) Works great!

Ready for a 2 Klick hike stringing WD-1A/TT wire down to the CP:

C-433/GRA-6 Radio Wire Intergration Remote Set

The dipoles all worked quite well even under the average/poor propagation conditions in effect at the time. The 10.7 cm Solar Flux never exceeded 67. The fo Critical Frequency for NVIS propagation probably hit around 8 mc for a few hours on Friday and Saturday.

The Inverted L usually works OK but not this time due to grounding issues. At our target AO ranges inside of 300 km the end-fed slant wire was predictably poor – don’t bother if you can rig a dipole; Verticals need not apply.

On the air! I love the sound of CW in the mountains.. DiDiDiDit DiDit
We were working 7050/3550 kc CW, the Day/Night West Coast Agent Guard Channel freqs. We had good CW comms with Andy on Curry Mountain, a 250 km shot on 7050 kc during mid-day.

Long range CW comms with a 10 watt QRP set

The 10 watt TRC-77 is a very capable CW field radio.  Above using the J-45 Leg Iron key working Dave in Livermore, a 152 km shot during our 2300Z comm window. With its tiny 15 ma receiver current draw, it was on for 4 days continuously – the 16 Amp-Hour internal battery barely noticed. Very reliable CW comms for hundreds of kilometers. Capable of thousands of km into the evenings especially with the simple dipoles when raised up to half-wavelength height. AN/TRC-77

Night Ops at the PRC-174S position.
Night time is the right time….Radio Silence and Light Discipline have been waived.

PRC-174S Night Ops on AM

We had good comms with the PRC-174S running 5 watts of AM on the 3985 kc MRCG AM net into the evening. This position was using a reconfigurable dipole rigged for 80/60 or 40 meters depending upon insulator jumper settings. Rigged about 10 meters up it worked well out to several hundred km to the Net members, friends and others.

The PRC-174S also works very well with 20 watts PEP on USB, in this case on the 3996 kc MRCG voice net frequency in the evening. He did hear some weak USB signals from the MMRCG 7296 kc net on Saturday at 0700 local, but alas, no joy. That’s a bit early for propagation out this way on 40 meters. Needs more solar ions over the Rockies…

(We had permanently disabled the PRC-174S transmitter Digital Squelch function as being incompatible with “regular” HF SSB radios.)

Note the machete on the table…(Zombies..)

Night Ops on the MRCG SSB frequency with the PRC0174

Above: The PRC-174S was running off two 12 volt AGM batteries in series, TRC-77 #2 standing by. The PRC-174S also provided solid daytime comms with Andy, 250 km away on Curry Mountain on 5357 kc. That when the continuous FT8 digital Ham stations always tying up that valuable channel took a breather. Or hopefully burned up. Sheesh!

“We’re The Fugawee”. Chief Wild Eagle when asked how his tribe got its name. F Troop.

Tactical Operations Center – fixed-mobile

Right here Chief: Both situational and geospatial awareness for coordinating Recon and fishing ambushes in the area. The Handy Dandy Tactical Operations Center/Command Post.
Our buddies all had VHF-equipped 4X4 vehicles plus HT’s, very useful up here while exploring…Essential along with LandNav skills for late arrivals trying to find our campsite.
In the Dark. At a place where we had not pre-planned to be. haha


I had the EF Johnson PRC-127ef on the Tactical Circuit; it’s an early squad and combat support radio. It is the third generation of (and a major departure from) the PRC-127 and PRC-127A, both of those being derivatives of Bendix King commercial radios.

It carries NSN 5820-01-509-9053 as the stock number. The US Army did not provide the usual Technical Manual, instead relying upon EF Johnson’s technical manual. This in line with the move to using COTS products direct from industry when appropriate.

The PRC-127ef is keypad programmable with many other optional features and accessories. A rugged, capable radio here in its element. They are long-obsolete now as the modern UHF Squad Radios are available.

Here for the long haul if necessary (or if the fishing is good…)
We can ALWAYS call for a resupply airdrop. Or Pizza.

Charging the field set batteries

The solar battery charging setup. Twenty watts = indefinite Ops with these field sets.

Once again, long range Recon beyond the FARP requires additional fuel and you don’t want a Red jerry can to give away your position. Condition BRAVO: (Refueling) Don’t transmit.

Refueling the Bronco Auxiliary Fuel Tank

The PRC-127ef hung out in that Day pack:

PRC-127ef in Day Pack

No windshields were harmed during the antenna launching evolution:

Antenna launching weights

(Another goal was to carry on with a 25 year tradition of the annual “Pigout” camping trip with friends, most of whom are now also licensed Hams, no pun intended. We even found a representative “MRE” to commemorate the event: Pigless bacon chips?? Wuuut?)

PIGOUT chips!

Living off the land?? (no)

Unfortunately for this guy Joanne was on it! She caught the biggest fish with her spinner.

Local trout for dinner

Local German Brown trout from the chilly Stanislaus River…

The Tactical ‘Taters didn’t stand a chance either…

Diced potatoes and powdered Onion Soup mix

Potato chunks in a cast iron frying pan, browned with a little butter. And powdered Onion Soup mix. Yummo!

Then there’s Patrol Pork Chops and Ribs Ala’ Recon in the heat of battle….

Recon Ribs and Portable Chops

Well, it is called “The Pigout” for a reason!

Many thanks to the West Coast Military Radio Collectors Group net members who listened up for, and checked into this little boondocks QRP operation. Always great to hear familiar CW fists and voices rolling in to the forest on this old military gear.

The Navy Radioman

Military Field Radio Comms: If you’re not having fun, you’re not doin’ it right…
No Shelf Queens! Get that portable Mil gear outside where it belongs!

Dit Dit