Hello all,
Just got my first CB from ebay, very cheap mobile DNT brand one (DNT Start 1, 40 channels FM) with a magnetic mount antenna, and I have some questions since I know very little about radios or electricity.
I'm gonna attach the magnetic foot of the antenna to a 2ft x 2ft steel sheet, as I read the antenna would be useless without it. Good idea?
For the power supply, I found a 220V to 12V car battery charger (4A - my radio needs 2A and 13.5V), so it has the black and red clamps at the end of the wires. Would this be ok as a power supply? Can I just cut off the car lighter socket from the radio wires and put the clamps on the cut wire ends (black clamp on black radio wire...)?
I don't have an SWR meter (yet). If I turn on the radio and listen to some channels and it picks them up fine, does this mean it's safe to transmit?
Any other things I could be doing wrong, please post, thanks!

Car battery chargers don't always put out steady voltage. You'd be better off to use it the way it was intended, just for best results. If you hooked that up to the battery, and the battery had a jump or a drop in power, it could fuck your shit up.

Car battery chargers don't always put out steady voltage. You'd be better off to use it the way it was intended, just for best results. If you hooked that up to the battery, and the battery had a jump or a drop in power, it could fuck your shit up.

Ahem..

http://en.wikipedia.org/wiki/Fuse_(electrical)

uhhgg.. :(

Ahem..

http://en.wikipedia.org/wiki/Fuse_(electrical)

First off, your link didn't work. Secondly, don't think that I don't know what a fuse does. I do work in radio, and have a degree in computer sciences and know that a fluctuation in voltage can spell disaster for any equipment.

Hello all,
Just got my first CB from ebay, very cheap mobile DNT brand one (DNT Start 1, 40 channels FM) with a magnetic mount antenna, and I have some questions since I know very little about radios or electricity.
I'm gonna attach the magnetic foot of the antenna to a 2ft x 2ft steel sheet, as I read the antenna would be useless without it. Good idea?
For the power supply, I found a 220V to 12V car battery charger (4A - my radio needs 2A and 13.5V), so it has the black and red clamps at the end of the wires. Would this be ok as a power supply? Can I just cut off the car lighter socket from the radio wires and put the clamps on the cut wire ends (black clamp on black radio wire...)?
I don't have an SWR meter (yet). If I turn on the radio and listen to some channels and it picks them up fine, does this mean it's safe to transmit?
Any other things I could be doing wrong, please post, thanks!

look.. i'm not trying to be snotty to anyone-- ya'll know when i do ;)

but the radio we are talking about is for a damned car for petes sake!!

of course a 12v WHATEVER (as long as the power supply is what the radio requires.. which is probably DC) WILL work..

ie, it is close enough to 13.5 to work (or should).

also DOUBLE check the output on whatever power supply you decide, with the ingnition/accessories, on AND off.. to verify that power is coming through.

you should be able to test/use the radio with that battery charger.. if the specs you claim are true.

and as long as your rated amps are = > what you need.. your ok there to.

and EVEN tho the pretty color wires *match* (in the auto)... does NOT mean you should just go ahead and ASSume that everything is ok..

you NEED to verify that teh hot is red (positive almost definitely with a car bat)...

do this with a meter that will tell you whether your hot is negative or possitive.

and it can never be stressed enough ** DO NOT EVER TRANSMIT WITHOUT HAVING A ~proper~ ANTENNA OR DUMMY LOAD * attached to the transmitter!!

good luck.. lettuce know..

Thanks Halvy. I bought a regulated 2A power source just to be sure I wouldn't fuck up the radio but it hasn't arrived yet. I tried the radio in the car and it powered up fine but I didn't receive anything, probably cause the car was inside the garage...
As soon as I get my power supply I'll try my radio with antenna on the roof, which should work better.
So uh... Picking up signals fine doesn't mean the SWR is okay and it's safe to transmit?

So uh... Picking up signals fine doesn't mean the SWR is okay and it's safe to transmit?

Unfortunately not. VSWR doesn't really come into play when receiving, only when transmitting. If only it were so easy as to adjust until you got a good reception...

Thanks Halvy. I bought a regulated 2A power source just to be sure I wouldn't fuck up the radio but it hasn't arrived yet. I tried the radio in the car and it powered up fine but I didn't receive anything, probably cause the car was inside the garage...
As soon as I get my power supply I'll try my radio with antenna on the roof, which should work better.
So uh... Picking up signals fine doesn't mean the SWR is okay and it's safe to transmit?

cb has very little chatter usually these days.. but try chan 14 & 19 for trucker s(i think).

someone told me the troopers or state still monitor channel 9.. but i dunno.. it may matter what area your in.

that plate prol is not necessary if you are going to mount it on a large piece of metal like your roof.

and the larger amps rating in that original bat charger should have been ok.. the amp rating is what YOU draw.. which would have only been 2a.

it's not like the charger (or whatever) just PUTS OUT 4 amps.. that is ONLY what it is desinged to draw, as it's maxs.

if you want perfection, get a *clean* power supply that will give exactly what you want (13.5volts)... and won't deviate more than a 1/10 of a volt, like most dc crap ps.

get a cheap 2nd test cb to make sure everything is working.

look.. i'm not trying to be snotty to anyone-- ya'll know when i do ;)

but the radio we are talking about is for a damned car for petes sake!!

of course a 12v WHATEVER (as long as the power supply is what the radio requires.. which is probably DC) WILL work..


A battery charger is NOT a power supply. Many battery chargers are 1/2 wave rectified, with no filtering or voltage regulation. Even thought the output is "close enough" to 12V DC, they just won't work.

Wall wart type battery chargers often are filtered and may work just fine.

They still sell CB's? I thought those went out in the 80's.

A battery charger is NOT a power supply. Many battery chargers are 1/2 wave rectified, with no filtering or voltage regulation. Even thought the output is "close enough" to 12V DC, they just won't work.

Wall wart type battery chargers often are filtered and may work just fine.

They still sell CB's? I thought those went out in the 80's.

hay Mc long time no see :]

yea i didn't consider if the batter charger would hold up even tho the volts and amp ratings seem fine.

i know with the wall warts that you NEED to check the voltage coming out tho.. cause ALOT of the time they are WAYYY higher than the item you want to power is calling for.

If it is just a small fraction (like 1-5%) higher, then you MIGHT be ok.. but this is an area that needs to be verified on a individual basis so as to not destroy your device.

I thought you were talking abought chastity belts.... Wrong forum.

First off, your link didn't work. Secondly, don't think that I don't know what a fuse does. I do work in radio, and have a degree in computer sciences and know that a fluctuation in voltage can spell disaster for any equipment.

Firstly, if you have a degree in computer sciences, maybe you could figure out how to make the link work if you were so inclined. :rolleyes:

A good portion of car CB's already have a built-in voltage fluctuation protection circuit.

If you were that worried about it, Im sure you're also familiar with the terms voltage stabilizer, and linear regulator.

Your computer's PSU will work fine, the quality from them is very good.