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Sometime back someone was looking for info on radio equipment for an M715. Here is some info I found. Hope it helps.
Radio: RT-524 or RT-246
also PRC-77 or PRC-25 with the AM-2060 amplifier will work with the antenna below.
Antenna Base: MX-6707
Antenna Whip: Lower AS-1730 and Upper AT-1095
I don't know if anyone else was interested, but I was looking for this info. I appreciate it, thank you.
Good info, the radio guy I've been dealing with says the RT-524 is the most common. I just started procuring all the radio equiptment 8 months ago. So far all I need is the radio itself and the triangular mount for the forward antenna AB-15. The rear antenna I have has three sections MS-116, 117, 118, and will not fit the MX-6707. (so if anyone has the right mast base to fit it PM me)
Can one of you knowledgable gent's tell me if the two antenna set up shown in the manuals section or the one mast set up I've seen in some photos is correct, PLEASE.:oops:
The antenna sections you have fit the AB-15 base. If you have two radios you need two antennas. If you have one radio only one antenna. The two antennas is common if you have the RT-524 and the auxiliary receiver (I forget the number) which has it's own mount. Or in some cases a vehicle used as a command and control truck might have two Rt-524 or an 524 and a PRC-77 type set-up. This allowed you to talk to two different types of units. The reasoning is or was that Infantry was on one set of frequencies, PRC-25/77 36-65 Mhz., the Armor was on a different band 28-36 mhz (or there abouts I've forgotten this stuff over the years) and Artty was on a lower band (26-28) or there abouts and therefor if you had to listen to say Artty and talk to the grunts you had the transceiver to talk to the grunts and the extra receiver to listen to the cannon cockers.
Try Fair Radio Sales in Lima Ohio they should have the antenna parts you need. Good luck finding a working Rt-524 the last demil requirement stated that a 1" hole had to be burned through the radio from the top of the case to the bottom of the case rendering the radio inoperable.
Where is a good place to get demilled/gutted/non-working military radios?
I've been looking on Ebay and a few other places, but they all seem to sell operational radios (or maybe it just appears that way?), and they are asking several hundred dollars for them. What would a for sure non-operational radio go for?
So what about the mount? I know everybody tries to get the sugar scoop mount (like I did) but mounted on the side of the bed you cannot get the 6707 base in the mount without hitting the side of the antenna base on the bed rail. Is the sugar scoop mount really correct? I am also wondering where it was supposed to be mounted. On the single wall bed side or on the stake pocket where the amber reflector is located?
I was able to get into the manuals this time. I got my questions answered.
There should be a bracket that mounts to the bed that then mounts the scoop to it thus keeping the ant away from the bed.
Quote:
Originally Posted by k8icu
Thanks for the info, I think I'd be happy with a nonfunctional radio for the money. I don't know about the giant burn hole though. Also the guy I've been dealing with is in Reno, Nevada and sells working and nonworking radios & equiptment. (kind of pricey for the functional stuff) here is his info:
Doug Stutzman
3435 Deer Foot Lane
Reno, NV 89506
He seems to know his stuff.
I had acquired about a week ago on the subject, Thanks everyone on the information!!
To use the sugar scoop mount you need a standoff bracket and backing plate.I have the plate used for 5.00,the bracket used 10.00,nos scoop 20.00 or all three for 30.00 plus shipping.Non working radios for 225.00.Look complete from the outside and the knobs and dials turn.Mast sections for the MX6707 are 50.00 per set.I carry all the mounts,cables,radio mounts and antenna sets for these Mseries trucks.You can call me at 1-859-749-5659.THANKS Tony
I had the triangular mount on my truck but didn't know what it was for, i figured it was for a radio antenna. It was beaten up pretty badly so I took it off. Now the more I read about it my truck my have originally had a radio installed on it....if so then there goes more money out the window! My bracket though was installed on the left side of the bed closest to the cab, I think.
If the truck had a military radio installed it should have had the antenna on the right side of the bed. Usually the jerry can and bracket sit on the left side behind the driver door on the bed side.Quote:
Originally Posted by jeep690
Many of these trucks saw use by fire departments, forestry and other departments and much of the antenna and radio brackets and mounts were added then and not always in the standard spots.
Randy, your right. it was mounted on the right side of the bed just behind the cab. Now i'm thinking my truck needs a radio system...
I had to look at pictures I took right after I bought it to confirm it's location. Right where you said it was
Just for everyone's info, the M-715 had either the RT-66, 67, or 68 series of sets depending if it was assigned to armor, artillery or infantry. Later years saw the RT-524 or RT-246 sets which covered all the frequencies. Many sets were mounted on the troop seats in the box with the remote head in the cab. Some RT-524 sets were mounted on the battery box and others on fabricated mounts above the battery box. If you have the antenna mount or the holes for the antenna mount on the right side (curb side) of the box, it probably had the RT-524 or 246 installed.
Good info Ron!
Just out of curiousity, did any of the M715's have the radio set mounted behind the passenger seat?
I have one truck that has a radio bracket of some sort still mounted to the back of the cab there and I saw another somewhere in my travels that had a similar bracket. Its about 12 inches by 18 inches and looks like a radio would slide into it.
Possibly an RT-524 mount. They slid in the horizontal but could hold the radio in vertical with no problem. No way could the older sets do that.Quote:
Originally Posted by randyscycle
Did the radios require the 100 amp alternator or could they be run on a truck with the regular 60 amp unit.
If the truck just had on rt-68 or rt-524 then the 60 amp alternator would work just fine. If the truck was required to have more than one radio then it would have to have the upgraded system.
If equipped with a ratt rig or other communications shelter, the 100 amp kit was installed. Not required for just a single VHF radio.Quote:
Originally Posted by kwai
Would there be any other reason to install the 100 amp kit besides the comm shelter?
I have a couple of trucks that have the cut-outs for the 100 amp rig. Be interesting to know what they might have been used for.
Non that I know of but strange things went on. There were all kinds of shelters, just like today, that had telephone switching, fire control (arty), and the like but I can't think of why any would need the 100 amp set up other then the ratt. The ratt draws about 45 amps during transmit and I run mine with the 60 amp alternator but you need some RPM's to keep up long term. The 100 amp systems we had would do OK at high idle. I'm transmitting short voice segments so no impact but if you run the TTY and need the inverters, the load climbs to 60 amps real fast. We ran some long message tapes in the signal corp so we might transmit for 20 min. at a time.Quote:
Originally Posted by kwai
Ok. What are RATT and RTTY abbreviations for. Your site doesn't say and I didn't quickly find an answer on google.
Ron, you're gonna get questions fired at you rapidly now......:D
One question I have is with a unit drawing up to 60 AMPS to power it, what was it actually radiating in terms of watts? I've seen some linear amplifiers for CB stuff that pull around 6-8 amps and they tend to boost output wattage like mad.
I'll get in line behind everyone else for an answer now.
RATT and RTTY is "Radio Teletype" TTY is Teletype" a RATT RIG was and still is an Army slang term for a "Radio Teletype Shelter"Quote:
Originally Posted by kwai
The older AN/GRC-46 sets were 100 watts but were AM for voice and FSK for RTTY. They used dynamotors to generate the voltages needed for the transmitter (some later models tried solid state power supplies but these were troublesome). All tube sets. Lots of loss in conversion. The T-195 transmitter in there needed 100 amps surge to get the dynamotors started and 60 amps to transmit. Add in the rotary inverters for the TTY gear and 24 volts for the old tube modulator and demodulator and you were way up there.Quote:
Originally Posted by randyscycle
The later AN/GRC-142 and 122 sets were 400 watts Single Sideband and AFSK for TTY. They are mostly but not completely solid state. The high voltage inverters for the amplifier are all solid state and much more efficient. Low inrush. Plus SSB is more efficient, you don't waste power on the AM carrier or the lower sideband so the current varies with your speech.
The quick answer!
Interesting stuff! Now one more......heh, heh......
Did that stuff tend to propagate at night like regular AM stations do? A 50K Watt AM station during the day has to throttle back to say 2K at night. Of course I am sure the communications were encrypted somehow, but that seems like a fair amount of AM power.
How far you transmit is dependent on conditions, atmospheric, night/day, terrain, and frequency used. Generally speaking, we relied on ground wave for point to point communications and selected a frequency related to the distance we needed to communicate. This is for the HF band, 2-30Mhz. At night, or even daytime if the conditions are right, you can transmit for great distances on some frequencies. I have worked the UK, and Germany sitting in my shelter with just the 15' whip during the day. In my Army era, reliable long range communications went by microwave stations set up in 2-1/2 ton comm centers.Quote:
Originally Posted by randyscycle
VHF vehicle sets like the RT-68 series and the RT-524 were generally line of sight and used mostly for convoy communications, vehicle to vehicle. The PRC series are portable and used in tactical situations for squad to squad and squad to command areas and could also talk to the vehicles.
That clarifies things!
I didn't realize though that this stuff was line-of-sight. I always tend to think of FM (88-108 Mhz) that way, but never think of lower band the same. Again, and I may be comparing apples and oranges, but AM bounces off the ionosphere and that changes after sunset, wouldn't these sets do the same?
The reason I am curious by the way, is that it would seem that in a tactical situation these communications would have been easier to intercept if the enemy had the proper frequencies. Sort of like the guys who DX shortwave broadcasts.
What "bounces" is not dependent on mode like AM/FM etc. but on frequency and conditions that are favorable to those frequencies at any given time. AM broadcast frequencies are at the right place for bounce at night but they would still bounce if they were FM at the same frequencies. However because of Doppler shift, they won't sound too good.Quote:
Originally Posted by randyscycle
FM transmissions at 50Mhz and even higher have been known to "skip" if conditions are right. Many hams have communicated across the pond on 50Mhz during the right conditions.
As for line of sight, VHF and above is generally that way. HF will "ground wave" and "skip" but since the skip is variable and unreliable, all military communications using HF were rated for ground wave distances. I often work several hundred miles on ground wave.
Today, almost everything military, other then the tactical radios, are satellite. The days of the ratt rigs passed after the first golf war.