Commo Gear for the GA Rally

[SCSG-G4]

Looks like I'll have a PRC-77 to go with the RC-292 Antenna (visible in at least one of the VA Rally pictures), and can bring a couple of the CPRC-26's (1/4 watt squad radio) if needed.

 

[tennmogger]

Thanks Mike, two radios makes one comm link!

Do you know what frequencies your CPRC-26's have in them?

Bob

Looks like I'll have a PRC-77 to go with the RC-292 Antenna (visible in at least one of the VA Rally pictures), and can bring a couple of the CPRC-26's (1/4 watt squad radio) if needed.

 

[SCSG-G4]

Bob,
They should have the standard "D" set (50.0, 50.2, 50.4, 50.6, 50.8, 51.0) in them I have one TNM Battery Adapter unit (BA-289/U, one home made battery adapter (uses 15 9V batteries, not the 10 of the TNM unit), and the 6V power supply unit from Italy. They have not been used in over 20 years, so I'm not sure how well they will work.

 

[Fireham]

Howdy Y'all! Planning on coming even though I don't have a vehicle as of yet. I do have a ham licence and a bunch of radio's! Tenmogger, I'm planning on building a 6M antenna this weekend (10/16) to bring with me. I've also got a push-up pole to mount it on. May bring both my push-up poles and mount a 2M antenna on one of them. My 33 Y.O. son is also coming with his ham license and he would love to ride in a vehicle in the ralley and provide commo. (He is a former Airborne Combat Engineer so he kinda knows his way around.) Looking forward to the rally and coming up to help and hang out. Had another ham radio buddy that was planning on coming, but his kitchen pass got pulled. Planning on arriving early afternoon on Thursday (10/21). Will be listening and calling on 146.52 as we get close. May try out my Yaesu FT857 on 6M if I can figure out how it works and get on the right freq. See you next week, 73......Fireham (Paul/N7SDQ) (Mike/Kj4GOO)

 

[Recovry4x4]

OK, it looks as if I'll be trading my way into an operable PRC-77 at the rally. Pretty sure it's operational but I don't have a dang thing for it and not sure what I can get with it. Hopefully will figure that out upon arrival. No license so I need a HAM with me or I can monitor in the event I end up with enough stuff to make it fly!

 

[tennmogger]

Hi Fireham,

This is great! As the date rapidly approaches it'll be good for people to post what equipment they have that's actually operational and going to be there!

I'll try to monitor 146.52 MHz as I approach Thursday also. I'll be driving down from near Knoxville on Thursday in my 404 Unimog radio truck. Anyone else driving south on Hwy 411 or I-75?

Many people have expressed desire to have 6m green radios ready to operate so hopefully we'll have enough operational sets of radio/antenna/power source/ham to cover all the convoys. Multiple mobile setups per convoy would be ideal. Lead vehicles and tail gunners can be radio equipped and both have comm back to camp HQ. If one end of the convoy is in bad terrain, chances are the other end will still have coverage back to camp.

In case ham radio links come up short, CB should be our next best frequency for ground wave coverage. My experience there is lacking so I won't name a channel and am open for suggestions. Sure don't want to guess and come up with one that is loaded with truckers or worse.

We'll have a base station set up on CB in camp, as well as 2 meter and all HF ham bands also.

BTW, I'll also have an 857 in standby use for 6m.

Bob WB4ETT tennmogger

 

[REGULATOR]

This is going to be fun,

I'll be with hanging out with Fireham, but also bringing a 6/2/440 HT as well as a 2m/440 mobile, and a 10m and CB

I may or may not have the M1009 with me, shoot I may be on my motorcycle but either way it will be fun.

 

[tennmogger]

It sure is going to be fun! This is only my second year so don't know that many people. Be sure to stop by the 404 Unimog radio truck and say HI! Then do that again several more times and I might remember who you are LOL. My wife says I have CRS.

Bob Tennmogger WB4ETT

 

[tennmogger]

A couple more hams have checked in so we're looking good for commo for the rally. I have been making last minute tests on equipment and tuning antennas for a couple of days. Today the AM-4477 amplifier refused to pass a receive signal back to the PRC-77. Luckily it was just a sticky K1 relay.

I've seen a few references on the 'numerous' GA SS rally threads of radio mounts for sale. If anyone has the AM-2060 mount for a PRC-77 and AM-4477, I'm interested.

Bob

 

[OPCOM]

I wish I could come to your rally. I would like to make a few comments about communications; maybe I shouldn't, because no doubt there are already some experts going to the rally anyway. Feel free to ignore it anyway.

In wooded and variable terrain, GMRS is the last thing I'd pick up. I have good luck with PRC-77 type stuff and CB, when using a full size whip antenna.

I've been fighting the FRS-GMRS battle so to speak in the TXSG for several years, but we have learned how to make them work well in almost any situation. Height is everything. If a 15-20FT mast and good antenna is set up at base camp, it may work well enough to cover the entire event. There are so many variables though, no one can make an absolute statement. I've found that the lower the frequency, the better the range in woods and 4x4 sort of places. I think that is a good general rule.

higher frequencies
subspace modulator^
lasers'
ships' signal lamps (morse code)'
microwave links'
cellphones - 900 MHz and up
GMRS*#
FRS*
HAM 440/70cm*
MURS - 154 MHz*
HAM 2 meters - 144MHz*
HAM 6 meters - 50-54MHz*
RT246, RT542, PRC-77, PRC-25, Racal TRA-967 - ~30-80MHz**
CB - 27MHz
semaphore'
smoke signals^
lower frequencies

^ not dependent on terrain or distance

' line-of-sight only

# recently the FCC abolished the $80 licensing requirement for GMRS radios.

* These radios depending on model and cost may also have a tone or digital squelch function. The tone or code should be coordinated by the event managers so that everyone has a way to join the net on the primary channel. Generally the function can be turned off allowing as many participants as possible to join.
Among FRS and GMRS The selection of the squelch function, and even of the channel numbering, can differ between manufacturers, but generally there is a "motorola" and an "icom" spec.
More information on squelch codes can be found here:
GMRS Web: CTCSS Compatibility in FRS Radios
FRS channel frequencies
Family Radio Service - Wikipedia, the free encyclopedia
-- This is not comprehensive but is just to show that some sort of coordination will help get everyone on the net frequency.

** some military radios require a 150Hz tone to be transmitted along with the voice by the other station in order to "open the squelch" and receive it. Because military radios have a wideband modulation characteristic, a HAM radio set to the same frequency should be set to "wide" and use the standard civvy 151Hz tone while transmitting. Radios like the RT524 and RT246 have a front panel switch setting for "old" squelch as well as a squelch knob, which is a "regular" squelch requiring no tone. The TRA-967 also has this feature but the squelch level is internally set (no knob). The PTC-77 and PRC-25 do not have this feature, except that they do have a momentary (spring loaded) position on the function switch that will fully open the squelch.

 

[Herb L]

I’ll be bringing some extra batteries for the PRC-77 & 25. NOS but don’t know if they are good. Also some 524 install kits, won’t help for this rally, but maybe down the road.

 

[phil2968]

.

higher frequencies
subspace modulator^
lasers'
ships' signal lamps (morse code)'
microwave links'
cellphones - 900 MHz and up
GMRS*#
FRS*
HAM 440/70cm*
MURS - 154 MHz*
HAM 2 meters - 144MHz*
HAM 6 meters - 50-54MHz*
RT246, RT542, PRC-77, PRC-25, Racal TRA-967 - ~30-80MHz**
CB - 27MHz
semaphore'
smoke signals^
lower frequencies

You forgot 2 bean cans and a string! Good for mess hall to porta john communication! i.e. Wreckerman! Are you comin' back to stir these grits!

 

[tennmogger]

Hi Opcom,

We appreciate your comments! You always have good advice for radio related questions here on the SS! Maybe you can join us one year?

Our comm plan is based on the same experience as yours, that lower frequencies will do better through obstructions, plus allow some terrain following.

6 meters is the lowest legal operating frequency for which abundant green radios are available. Mobile/portable antennas are manageable on this band, too, which can't be said about 75m, fer example!!

Using our 'green radios' is one of our priorities. If the USA versions of the PRC type radios covered {edit} 10 meter band (as does the SEM-25, etc) then we'd be operating down there. We will have several elevated antennas, perhaps to 40-ish feet, if guy rope placement doesn't take up too much room.

CB is still a backup for us, being roughly half the frequency of 6m, and should have somewhat better propagation. CB is always limited by the quality of many CB radios (and the idiots that always seem to show up on frequency) and awkwardness to move a complete setup from vehicle to vehicle.

Our green radios are well designed and rugged, even waterproof. Take a PRC-25 or -77 for example, with internal battery, selectable short or long antenna choices, tough mike/headset choices, it's a great grab and go radio....as you well know.

Bob WB4ETT

 

[REGULATOR]

Bob, do we have any more simplex freqs we want to use?

I'll be hooking up with Fireham enroute, will eb on simplex 2m, as well as can have a CB/10m up and running in additional to the 6m.


I thought I read somewhere that there was a 6m freq we were thinking of trying out.

 

[tennmogger]

Yes, 51 MHz on 6 meter ham band. That will be our primary frequency for communications out to the convoys, and fixed locations in camp. Anyone who wants to operate there can set up a station from their camping spot, up at the eating area, carry around their packset, etc. This ham frequency has been defacto green radio frequency for years. If the band opens we might even get some contacts out of the area. Sunspots are increasing and we might get lucky.

On CB, how about channel 4. That's 27.005 MHz for the HF green radios. I'll have one "listening" there (don't quote me, I'll deny it LOL).

2 meters (handi-talki friendly) would be handy around camp, too, using 146.52 MHz for calling frequency. That's the national calling frequency so hams in the area might respond, and that's ok. If a conversation gets long, please move it off the calling frequency.

Tactical callsigns: It's fine to use any tactical callsign you want, like "convoy leader" (use good taste!). Just give your ham radio callsign every 10 minutes. Tactical callsigns will have more meaning than a ham callsign to others in the convoy or back in camp.

When I get there Thursday I'll be looking around for the tallest tree still available (it's a ham thing, not a dog thing).

Bob WB4ETT tennmogger

Bob, do we have any more simplex freqs we want to use?

I'll be hooking up with Fireham enroute, will eb on simplex 2m, as well as can have a CB/10m up and running in additional to the 6m.


I thought I read somewhere that there was a 6m freq we were thinking of trying out.

 

[REGULATOR]

OK, I'll be on all three thursday

 

[tennmogger]

Report on communications at SS Georgia Rally, October, 2010

At HQ comm:
Paul Wittenborn “fireham” N7SDQ
Michael Wittenborn KJ4GOO
Chad Tackett “regulator” KD5KRE
Bob Ragain “tennmogger”, WB4ETT, 1965 Unimog radio truck

On the convoys:
Joe KJ4PQW in his Gamma Goat with PRC-25.
Roy ChevyC60, WB4GSL, in his M-151 with installed RT-524 and antenna.

Others,
Mike, SCSG-G4, thanks for bringing your AT-292 for backup use.
Jamie “Jamieboy”, KD4NXY, pair of PRC-77’s and Clansman PRC-351 radio gear

We had several volunteers for setting up and manning the HQ Comm center during the rally. They were Paul Wittenborn N7SDQ, Michael Wittenborn KJ4GOO, Chad Tackett KD5KRE, and Bob Ragain WB4ETT. Being hams, we had various radios and antennas to try out. We did not have complete setups for installation in other vehicles. The original military vehicular installations would have been ideal for that use.

Our primary goal was to provide continuous communications with radio equipped participants on the convoys. That goal was poorly achieved due to lack of radios in the convoys. In case of emergency, radio traffic could have been handled through Joe. Thanks, Gamma Goat Joe, for being there and having the capability!

For future GA Rallies, if vehicle operators have radios installed, comms will work. Note that the Amateur Radio license Technician class is easy to pass, and no code is required now.

A secondary purpose for the HQ Comms operation was to check out radios for other SS members at the rally. Six PRC-25’s or ‘77’s and two RT-524’s were checked. Most radios worked, but a couple had problems in basic function, like ‘dead’ (very basic!), or no transmit. A couple of bad headsets or mikes were found, then radio operation was verified by substituting good handsets.

Here is what we learned about comms around Durhamtown this past weekend:

“It takes two to tango”. We were surprised at how few operational radios were installed in the trucks. Many of the vehicles had antennas, some had radios, but…few were operational. No need to send a ham along if there is no installed radio to use! For next year, we may have a portable package to install into a selected vehicle. This would include a radio, amplifier, antenna, and cabling.

The only operational mobile setup was Joe in the Gamma Goat. His radio was not installed, just used when he could get hands free to orient the radio, antenna, and handle the mike. We talked to Joe several times when he could get to the radio. Later Joe took us on a ride in the Gamma Goat, and, using his radio, we made successful tests back to camp. A vehicle mounted antenna would make a huge improvement in signal level.

A valuable contribution was made by Roy, WB4GSL, “ChevyC60”, whose RT-524 was receiving but not transmitting. Roy was on the convoys and came by later to report that he was hearing us calling the convoy with a loud and clear signal, everywhere the convoy went. This was a complete installation and it worked (receive only) as intended. Roy, thanks for the effort! This proves that the concept of using tactical VHF radios at SS GA is sound.

Asking around, we found no one using CB, so our CB setup was not used during the event. CB actually has possibilities, being a lower frequency to help penetrate the foliage, having some terrain following capability, and requiring easily available equipment. CB deviates drastically from the goal of using Green Radios though, and tends to be revolting to listen to for any length of time.

FRS/GRMS handitalkies were used for coordinating within the convoys, and apparently worked well. FRS and GMRS frequencies are poorly suited for communications over rolling terrain and through thick forest, no matter if the box says “works over 5-7 miles”. Our testing showed that the FRS signals back to camp dropped off in the first quarter mile after the convoys departed. Chad, Michael, and Paul used external antennas on sensitive ham transceivers to try to hear the FRS signals, with no luck.

More on Joe’s success: Joe’s PRC-25 was using the 3 ft antenna most of the time, but he could deploy the extended 10 ft antenna when he was stopped long enough. The longer antenna makes a noticeable difference. Problem is, the PRC-25 is low power, just half a Watt or so, and that’s not enough when the trail drops into the lower areas. Joe could have provided any needed emergency communications though, even if he had to move out of a creek bottom to do so. With an amplifier and full length antenna, Joe could probably have continuous coverage, even in the low areas.

Our “green” HQ Commo setup used a PRC-77 into an AM-4477 amplifier with a measured 30 Watts out, fed into a tuned ground plane antenna at about 30 ft. Paul had the best 51 MHz antenna, a J-Pole that he built, and it was raised on a pole also. A ham radio tuned to 51 MHz was used on the J-Pole antenna and it worked well. We had no trouble talking out to about 6 miles, the longest test we tried.

Thanks to Clinto for allowing us to set up on the highest spot in camp. Every foot of elevation helps.