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Radio advice need
Posted: Mon Jun 25, 2012 12:23 pm
by DFoley
I just purchased a VRC-9 Tactical Vehicle Radio station for my M38 (RT-67 transmitter). I have several questions. How specifically and exactly where is this radio to be located within the jeep. More specifically should I use the wooden blocks (i have them) or not? And exactly what size bolts and exactly where should the bolt holes be drilled. I'm very nervous about drilling holes into my jeep! I have seen diagrams and photos examples of it Radio Station where the rear seat is (rear seat removed) on the passenger rear tire well and on the drivers rear passenger well. Is there a "more correct" location? Or is it simply a personal choice? Personally, I think it looks best on the rear passenger side tire well. Primarily because it is closest to the axillary radio plug immediately behind the passenger seat. That brings up another question...my radio station has two (positive and negative) power terminals which I'm assuming are to wired directly into cowl battery. I would prefer to utilize the auxiliary radio plug. The auxiliary plug is a 3 pin female type (+, -, ?), however, my radio only has two ends (+ & -). What is the third connector on my auxiliary radio plug for, and can I get the appropriate plug to attach to my radio station to utilize this plug? I have attached a links to a few photos of my VRC Radio Station and my auxiliary plug to which I am referring to.
https://plus.google.com/u/0/10751641194 ... WEniMEmQhr
Thanks,
Dan
Posted: Mon Jun 25, 2012 12:47 pm
by evanso1975
Regarding the power outlet, mine only has A & B wired up. Outlet C is not connected (the rubber seal in the back of the plug has only two cable holes in it). Maybe this outlet was used for another function on different vehicles/equipment?
Owen.
Posted: Mon Jun 25, 2012 1:11 pm
by DFoley
Yea...my auxiliary radio plug also only has two wires wired up (positive to the battery and a ground). The third terminal is not connected to anything. what's up with that? This is supposed to be the correct power plug for this radio system...isn't it?
Posted: Mon Jun 25, 2012 3:45 pm
by OKCM38CDN
Dan,
I do not know if you are an amatuer radio operator or not so I am going to relply as if you are not... getting a license is very easy and the FCC has done away with the requirement to learn Morse code...
The radio would generally go on the driver's side and be mounted using the blocks and Mount MT-299 (last I knew this was a hard mount to find and expensive if you find one), this will hold the power supply PP-112(24 volt) PP-109 (12 volt) and the Radio... (one of the following, RT-66, RT-67 or RT-68) The power cable runs thru a channel from the passenger side to the mount... John at Midwest Military has the radio channel advertised on his website...
Another way to mount this set is using the MT-297 mount and this is generally across the rear of the jeep on both wheel wells and the rear seat is generally taken out... this mount holds lots of equipment and is basicly the setup for a command vehicle... I use a MT-297 as a bench set up to run my radios in the shop to test them and do repairs using a 28 volt power supply...
The cable will have only 2 lines used the A & B lead... the C was there in the event of a failure and the cable needed to be rewired... common practice in the military (at least in my time)...
I have a fully functioning RT-68 setup in my M-38CDN and have the license to operate it on the 50-54 Mhz band... Please keep in mind these radios are FM and considered Wideband (20Khz) channels... todays standards are 5 Khz channels...
If everything is operating properly then the 25 amp generator will easily power the radio gear and the rest of the jeep...
I use my setup to keep in touch with the wife as I progress thru the local parades... she has a civilian radio in her van; we are both amateur radio operators.
As for mounting Wes, had the mounting drawings in the gallery under radios...
Hope this helps...
73 (Best Regards), KB1ZQ
PM me if interested in getting a license if not already so...
Posted: Mon Jun 25, 2012 4:13 pm
by DFoley
Hal,
Thanks for the advice. I do have the MT-299 mounting bracket and the wooden blocks. I have seen drawings of the radio mounted on the drivers side, but never any actual pictures of it mounted on the drivers side. All the pictures of radios installed in jeeps have always been on the passengers side. The passenger side seems to make more sense because that is the side the plug is located on and would therefore negate the use of the channel to cover the power cord over to the auxiliary radio plug.
I have downloaded the installation files, but they have proved to be less than usefull because of their poor readability.
Also I'm not currently licensed but anticipate doing so shortly.
Thanks for your help,
Dan
Posted: Tue Jun 26, 2012 8:15 am
by wesk
The passenger side mounting was rare in the military. Civvy owners do it so they can operate the radio and drive the jeep at the same time. The military usually had a radio operator in the passenger seat. Right side mounting helps with weight distribution as well.
I have the VRC8 (RT-66 Armor), 9 (RT-67 Artilliary) & 10 (RT-68 Infantry) installation drawings in my album:
http://www.willysmjeeps.com/v2/modules. ... _album.php
Rod Nowland makes the oak blocks.
Posted: Tue Jun 26, 2012 10:32 am
by DFoley
Wes,
Thanks...the drawing in your person folder is more what I was looking for...I should have thought to look there first.
I have a set of Rod's oak blocks upon which to set this radio station. I'm guessing I can install it anywhere on the drivers side wheel well. But the diagram seems to indicate that it should be installed as far forward as possible.
Thanks,
Posted: Tue Jun 26, 2012 10:39 am
by wesk
seems to indicate that it should be installed as far forward as possible.
So the operator can reach it of course!

Posted: Tue Jun 26, 2012 10:45 am
by DFoley
What is the correct male end 3 pin plug that will connect with the 3 pin female auxiliary radio receptacle behind the passengers seat? My MT-299 simply has a power cord with two battery terminal type connectors (+ and -) be be connected directly to the Cowl battery. I would like to exchange this for the correct plug to use my already installed radio receptacle.
Posted: Tue Jun 26, 2012 3:59 pm
by pockers
Hi
Ive gotthe same setup for my m38a1 and am looking to mount on the passenger wheel arch
Think ive got everything except the wood blocks - do you have apics or dimensions of your ones?
Would really appreciate pics whenyou getit installed
With thanks
Pockers
UK
Posted: Wed Jun 27, 2012 7:40 am
by skyjeep50
Posted: Wed Jun 27, 2012 8:01 am
by wesk
This is the wood spacer used with the VRC8, 9, 10 on the M38 and M38A1 wheel house with the MT-299
http://www.willysmjeeps.com/v2/modules. ... pic&t=5167

Posted: Thu Jun 28, 2012 2:40 pm
by pockers
Hi
Thanks for the pics they are a great help
Can i pick your brains?
Can you still fold the rear seat up? When itried mine in place the seat wouldnt fold - do the wood spacers solve this?
Thanks
Posted: Thu Jun 28, 2012 2:42 pm
by pockers
Ps - do the spacers run front to back or left to right?
Posted: Thu Jun 28, 2012 3:56 pm
by skyjeep50
With the radio mounted as far forward as possible on the wheel well, you still can't fold up the seat. My MT-299 does not have a wood spacer underneath but I don't think that will make any difference since the radio mount will still project over the edge of the fender well. The seat can be removed by lifting it out on one end.