12V systems? AN/VRC-64

[Whiterabbit]

Hey all.
I have a 12V Military Rover and a complete AN/VRC-64 set up and a PRC77 manpac and was wondering...... Is there any way to run the VRC-64 set in a 12V vehicle or is ther any radio setups that would work in it? Pretty much got the whole setup and have made up a batt. for the manpack with rechargable RC car batts.
Am I just outt'a luck and have to mount a CB??
Thanks all!

 

[papakb]

The 77 will work on 12 volts just fine, the 6707 matching unit doesn't like it. Running the 2060 on 12 volts also stresses the voltage regulator circuits on the card in the 2060 and they are getting harder and harder to find any more. Remember, most of this stuff is 50 years old now.

 

[Whiterabbit]

Ok, kind'a figgured the matching unit in the ant. mount and the power amp needed 24V. Just was hoping you could run 12V.
How about one of those DC-DC /12 to 24V 10 amp step up converters you see on ebay? Would one of those work?

 

[tennmogger]

PRC-74, 74B, and 74C are 12v. These are manpacks but no reason they could not be installed in a vehicle.

PRC-320 (British Clansman) HF radio and PRC-351/352 series VHF radios are 24v but have a 12v DCCU available (DC charging unit) that runs on 12v vehicle and keeps 24v battery topped up. I use that combination in my 12v civi vehicles. Works fine.

The Clansman equipment would be perfect for the Rover. That was original equipment!

Bob WB4ETT

 

[Whiterabbit]

I'd love to have a Clansman radio in it but I can't find any here in the states! LOL!

 

[Whiterabbit]

OK, found some info. Under the radio is an EMCU-116 12v to 24v inverter.
I'm assuming the switching power to the ant. mounts don't ground to the body?
Gett'n closer to putting it in.
OH, this isn't my truck. It's pics I found online for inspiration.

 

[Whiterabbit]

This my truck and some of the gear I want to install. Still digging through the garage and finding radio bits!

 

[papakb]

Follow this link and it'll take you to a decent voltage doubler.

Step Up 12 Volt to 24 Volt DC DC Converter Regulator 700 Watt Peak in Box | eBay

700 watts is more than enough to power up a 524 and some additional stuff. That works out to about 30 amps, so even being conservative you'll have plenty of power.

Kurt

KG6KMJ

 

[Whiterabbit]

Thanks! Haven't been able to track down an affordable 524 (and I don't think there's one laying in the garage)so that's why I running the prc77's in an VRC64 set up. Won't have alot of range like the 524 I guess? But I can pull and tote them if the truck takes a crap!
I know I ask alot of "stupid" questions but I just don't want to fry the poor radios.
Thanks! I'm off to fab the ant. mount!

 

[jamieboy]

hey jinxkat, sent you a PM about a clansman radio. Don't know if you saw it or not. Should be in your mailbox. The truck is lookin good!! Can't wait to see the radio gear installed.

 

[Storm 51]

That is very nice looking Rover, Jinxkat.

Good Luck with your radios!

Storm 51

 

[scottgs]

jinxkat, I think I may have camped next to you at the GA rally? FWIW, I have in the past mounted both the VRC 64, AS-1729/MX-6707 and PRC-77 in a S-III Rover (not the Lightweight I had at the rally). In general, I concur with what has already been said. I think you have some good options to install that equipment.

Option 1, install just he PRC-77 and build/modify a power cable to run it straight off 12VDC power. The MX-6707 will be fine if manually tuned with the switch on the bottom of the base.

Option 2, install the complete VRC-64 by using a 12VDC to 24VDC converter. 12VDC to 24VDC commercial converters are not hard to find, and generally work well.


Orrrrr... Option 3, sell the PRC-77 (VHF) eqmt. and buy a complete "clip in" British PRC-352 (VHF) set as originally installed in Rovers, and then for the utlimate in capability, compliment it with a PRC-320 (HF). I personally would likely chose this option, as the PRC-352 is a more versatile radio than the PRC-77, plus it's original to the vehicle. But, they do still require 24VDC power. Having said this, I have to admit that I have no experience with the PRC-352, but I certainly do with the PRC-25/77.

The other Brit radio mentioned, the PRC-320 (HF), is the equivalent (in capability) of the radio I had in my Land Rover at the rally. These HF radios are long range radios which can talk across the country, or world. The radio in my Rover at the rally was an Israeli Micom-XR, not the Clansman PRC-320, but they do the same basic thing.

Of course to really make the most use of any of these radios, an Amateur Radio license would be handy. Got to get that plug in there.

I'm not an expert on any of these radios, these are just my first thoughts.

Garret

 

[Whiterabbit]

Whooo weeee! That PRC320 is nice! Down side is I think the wife would pour hot grits on me while I sleep if I bought that! $$$$! I think I'll have 100 bucks in this system 'cause I had almost everything already, just had to dig it all out of the garage.
Oh, I blame you for the wife want'n a small MV like your Light Weight and me being interested in radios again! Looking to get the tech lic. to be legit, and trying to talk my brother outt'a a free uncut M151a2 he hasn't done jack with for years.
Going out and take some pics of the setup.

 

[Whiterabbit]

Getting there! The 700w 12v-24v converter showed up in the mail Sat(60 bucks). I'm fab'n up the Ant mount at work out of some scrap 6061T6 aluminum I had and I need to go get some more 8 or 10ga wire for to power the converter.

 

[Whiterabbit]

OK, Hmmmmmmm.
Hooked up power to the AM-1780 (J50 ran a 4723 cable off of J501 to the MT1029A, removed the cover on the back and moved the buss bar to the left to E22. Ran a 4723 cable off of J507 on the AM-1780 to my vic box which is a C10456. Pulled the PRC77 just in case and powered it up to see if the system is ok so far. I have hand mics on both connectors of the vic box.
ZIP! Nada! No light on the 1780 box. No power. Grrrrrrrrrr. Do the 1780's burn out?
I'm following TM-5820-498-12 chapter 2-5
Any insight??
Thanks!

 

[Whiterabbit]

Ok, the TM is as screwed up as a football bat!
Under chapter2, para2-5 (3) it says to run power directly to the AM-1780 and ,in turn, to the amp power supply (AM2060).
But........
You look at fig.2-3 it shows power running from a MX-7777 to the MT-1029 and a CX-4723 running to the AM-1780.
So, which one is right?
I found a MX_7777 with cables in my pile o' crap(garage) but the power input lead has the 3 pin conector on the end you hook up to the batt. Cut and solder ring terminals on that end?
Starting to think the whole intercom thing was a bad idea.

 

[Whiterabbit]

Whew! Bad C10456 and a bad mic on top of a intermittent short in a cable. Swapped out and now all good except the light still doesn't come on on the 1780. (yea, I turned it to open) But I did find a headset while digging around.
Will try to get some pics up tomorrow. Still need to weld out the ant. base mount.