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Radio 24vdc to 12vdc ?

GRHooten

Member
Joined
Oct 24, 2006
Messages
7
Location
Hawaii
Anyone know the best way to convert 24vdc to 12vdc?
I want to replace the old 24v radio with a 12v new one which are much easier to get.
Any suggestions on converters?
Machine is a Cat 307 SSR 24vdc system
Thanks,
Gary
 

BrianHay

Senior Member
Joined
Jun 21, 2007
Messages
514
Location
Nanaimo B.C
I don't know what they cost, I have never bought one myself but you can get converters for that. Most iron I have operated that had cb's had them. I tap into them to plug in my satilite radio. Check out some electronics stores and you will probably find one.
 

nedly05

Senior Member
Joined
Jan 28, 2006
Messages
1,801
Location
Adk. Mtns, NY
We had to get a converter to put the 2 way radio in our loader,I dont remember what it cost but it was really easy to put in.
 

Komatsu 150

Senior Member
Joined
Aug 17, 2007
Messages
673
Location
Northern Illinois
Napa has two different models available. I've used both, the little one is only 2 amps or something and not built as well as the larger one. You may have to arm wrestle the counter guy to convince him it exists and to make him look it up. Cat has one that is very well built but rather spendy. Electronic stores around here are completely clueless.
 

Squizzy246B

Administrator
Joined
Sep 9, 2005
Messages
3,388
Location
Perth, Western Australia
Occupation
Digger Driver
If you have 12 volt batteries connected in series you can just pick up 12 volts from the first battery or bank, run a fuse and you have an "unregulated" supply. Check with a meter to make sure. The CD player we got awhile back was capable of running off anywhere between 9 and 16 volts.
 

GRHooten

Member
Joined
Oct 24, 2006
Messages
7
Location
Hawaii
Thanks for the suggestions
I've checked with NAPA but have'nt had any luck. I just went onto Ebay and found a couple of 24vdc to 12vdc converters so I guess I'll pick one up.
I thought about the hook up to the 1st battery but, I would rather have the radio power to be switched at the key so things won't br left on by accident.
 

surfer-joe

Senior Member
Joined
Mar 25, 2007
Messages
1,403
Location
Arizona
Radio Shack has them at a fair price, others do too as you have found. The Radio Shack model, which is likely similiar to the 2 amp NAPA version, is not what one would call a long term investment. In other words, they usually do not last too long. The Cat convertor is top notch. I've never had a problem with them. They are for the serious user however, very expensive tho not so bad as when they originally became available back in the late seventies.

There is a good reason why not to hook to one battery only, doing so puts a constant load on that one battery. The alternator, being stupid, thinks both batteries are needing a charge, and proceeds to do just that. This tends to cook your batteries and shorten their life. There is a Cat Service Bulletin about that from years ago available. Ask your Cat PSR guy to look it up for you. AC Delco had a brochure about it as well.
 

Komatsu 150

Senior Member
Joined
Aug 17, 2007
Messages
673
Location
Northern Illinois
The local county highway department went through 8 or 9 batteries on a motor grader after they wired the FM communications radio to one battery. Amp draw was pretty heavy and the other battery would cook to death from over charging.
 

72V

Well-Known Member
Joined
Aug 25, 2007
Messages
121
Location
Oregon
Occupation
grader, cat, excavator hack
I've experienced the same thing on a 14G wired that way. And if you shut off the night switch with the radios still plugged in, they would fry.
 

GRHooten

Member
Joined
Oct 24, 2006
Messages
7
Location
Hawaii
Yeah, I did'nt want to hook up to only one battery, like surfer-joe said there would be a unbalanced load from the two batteries and the charging system will keep charging them at 24v - 28v which will overcharge the battery that is not carrying the radio load .
NAPA wanted $205 for a 10amp converter. I found a couple of 10 to 15 amp ones on Ebay for $40 to $60. I going to order one and try it out. Hopefully all will go well.
 

lgammon

Senior Member
Joined
Mar 26, 2007
Messages
303
Location
kingsport, tn
look at you machine closely our 953 had the origenal radio robbed so i went through what you are now only to find that it had the cat converter already in it
 

BeaudesertSand

Active Member
Joined
Aug 29, 2007
Messages
26
Location
Australia
Occupation
Plant Operator
Our old 966C has a radio just hooked to one of the 12 volt batteries, works okay, tried with the volvo dump truck = bzzzzzzzt for the radio. A radio Shack equivilant shop here supplied a 24 -12 convertor and its been happily filling my cab with crap music ever since.

My .02 would be: get a convertor.. Or Invertor, whatever its called.
 

tw_692000

Well-Known Member
Joined
Nov 14, 2007
Messages
45
Location
indiana
Occupation
heavy equipment opperator /assistant foreman
Anyone know the best way to convert 24vdc to 12vdc?
I want to replace the old 24v radio with a 12v new one which are much easier to get.
Any suggestions on converters?
Machine is a Cat 307 SSR 24vdc system
Thanks,
Gary

my volvo has a converter for the am/fm radio that just went bad.....the radio being 12v and machine 24v it was if i remember right cost $286 from volvo, but the 2 way radio man put one in for just the 2 way don't know what it cost but there must be a difference in them but i don't know what it is because he couldn't use the one on the machine....
 
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