Crossing Voltage for Fun and Profit! (just fun actually)

amateurhour

Okay, so I purchased this CB radio and antenna from Goodwill for like ten bucks. It's got three wires coming out the back of it that go to some kind of adapter clips (well, two of them do, the white and red wires. The black wire just keeps going) and then all three wires meet into a cigarette lighter adapter. On the back of the radio it says 13.8 V DC

I've got a standard PC power cable. The kind with the three pronged adapter that, when you cut it open, has three (usually) matching color wires. Sometimes one of them is green. I've cut these up all the time to wire them directly to CFL bulbs for lamps, and stuff like that, but that's not what this is about.

What I would like to do is cut the power cord, wire it to the three wires coming from the CB radio so that I can plug it up in the house and use it. This is a pretty simple process.

The 13.8 V DC kind of worries me though. I want to make sure the power is right between the device and the wall and it's not going to A) Instantly break my shiny new/old radio and B) Burn down my house or crash my breakers.

Is it safe to do what I'm planning to do? The end result is that I would like to have a CB radio in the house to play with from time to time. I can just buy one of those cigarette lighter to AC wall adapters from radio shack, but I thought this might save me $15 bucks.

So is it pretty simple, or am I going to burn the house down?

Thanks H/A!

Technicality

Buy the adapter.

13.8v DC and mains (~120v) AC are very very different.

matt has a problem

You won't burn the house down. You will be treated to a possible smoke and light show, as you put 120 volts into something only made for 14.

Fats

It won't even be an exciting smoke and light show, unless you manage to electrocute yourself in the process.

But no, your 13.8VDC radio will not be happy with 120VAC.

amateurhour

And this is why I love asking questions before I go plugging things into the wall.

Thanks, you can close this topic. I'll pick up an adapter.

LuckyYou

Keep in mind that although you'll be able to receive transmissions, you won't likely be able to transmit very far since the antenna will be indoors.

amateurhour

LuckyYou wrote: »

Keep in mind that although you'll be able to receive transmissions, you won't likely be able to transmit very far since the antenna will be indoors.

I plan to either attach it outside the window or use an old 300 watt amp I had from my old radio that was in my car.

I'm really only messing with it to see if I still have an interest in it because I was thinking of getting my radio license for higher end equipment. That's all.

phekno

amateurhour wrote: »

LuckyYou wrote: »

Keep in mind that although you'll be able to receive transmissions, you won't likely be able to transmit very far since the antenna will be indoors.

I plan to either attach it outside the window or use an old 300 watt amp I had from my old radio that was in my car.

I'm really only messing with it to see if I still have an interest in it because I was thinking of getting my radio license for higher end equipment. That's all.

You're going to use an old 300 watt amp from your car for the CB? Is it a CB amp (i.e. one meant for CB radio transmission)?

amateurhour

phekno wrote: »

amateurhour wrote: »

LuckyYou wrote: »

Keep in mind that although you'll be able to receive transmissions, you won't likely be able to transmit very far since the antenna will be indoors.

I plan to either attach it outside the window or use an old 300 watt amp I had from my old radio that was in my car.

I'm really only messing with it to see if I still have an interest in it because I was thinking of getting my radio license for higher end equipment. That's all.

You're going to use an old 300 watt amp from your car for the CB? Is it a CB amp (i.e. one meant for CB radio transmission)?

Yes.

back in college this dude who was really into radio equipment set me up with a modified CB radio that was putting out about 30 watts over the normal 4, and a 300 watt amp. I could reach New Mexico from Alabama on a clear day. We used to use them instead of cell phones when we were on campus.

Although it was probably illegal as hell though, I'm guessing.

Anyway, I want to get back into it, and maybe go a step further and get a ham radio license.

MrOletta

I'm hoping to go take the exam for my license in a few months, too!

I would say be careful, because FCC limits the CB frequency to 4 watts without your license. Normally people won't care, as truckers drive around with 30-40 watt "export" radios all the time, but just make sure you don't jump onto the other bands, or the FCC might come knocking on your door.

amateurhour

MrOletta wrote: »

I'm hoping to go take the exam for my license in a few months, too!

I would say be careful, because FCC limits the CB frequency to 4 watts without your license. Normally people won't care, as truckers drive around with 30-40 watt "export" radios all the time, but just make sure you don't jump onto the other bands, or the FCC might come knocking on your door.

Honestly I probably won't do the amp. I'll stick with 4 watts just to play around until I decide to either get/not get a license.

The reason I wanted to get back into it is because I found this old software setup from the 80's based on military plans where you can take a linux/unix machine and connect it to a ham radio to send packets to another machine on a bbs network. it's slow as hell, but the idea of a radio based chat program is cool.

Beltaine

Ahem

You need one of these

Do something besides just frying it all with 120v AC and you'll have more fun and might learn a something or two.