CB question

[JeepJunkie]

ok i got me a cheapo CB from radio shack and a 4ft fiberglass antenna. Its all mounted up and the CB is grounded to the frame and is getting power from a slot in the fuse panel labeled "BATT" I havent had a chance to bring it somwhere to get it tuned, and i dont feel like buying a SWR meter. but it does work but there are problems. With the car off there is a little static noise on most channels but some channels have a sort of whine to them. Is this because it hasnt been tuned? now with the car on, i get MAJOR noise, i heard someone call it alternator whine or something like that. It is more of a buzzing sound and when the engine is revved it gets a little louder. I can get rid of the noise with the squealch controll but after i do that i cant hear anyone talking. Which i would assume its because they are out of range and the signal isnt strong enough to get past the squealch....is this normal to hear all that noise?? also the antenna is a no ground one made for boats or motorhomes that are fiberglass, is that ok? The strongest signal i got was from someone who was less than a mile away and i was able to get rid of the buzzin with the squealch but as soon as he said something the buzzing came back, then went away when he stop transmitting....anyone have any ideas????

[blkTJ]

try taking the power directly from the battery itself. that should help.

there are also noise filters for that kind of thing I think. haven't tried one, don't know if they work.

[jmbrowning]

The whine is probably from your alternator. Go directly to the batt and ground as close to the radio as possible. To minimize this noise further consider putting a capacitor in the power circuit. Very interesting article on hunting down RF interference in your mobile install.

Tuning SWR only improves transmit and doesn't affect your receive. SWR adjustment is worth it if you have the capacity in your antenna. Many cheapo ants don't have it.

The NGP (no ground plane) ants are not as effective as standard antennas of the same length.

[JeepJunkie]

any idea where to look for those noise filters?

I did take power directly from the battery and i still had a crazy buzzing sound when the car was running.

I dont have a radio so i cant ground to that...right now its grounded to the side of the body in the engine compartment. Should i look for another place to ground it say like behind the engine compartment towards the rear of the car? the antenna that i got i wouldnt call cheap...it was like 45 bucks. as for it being NGP i guess i shoulda looked into that more to see about it being less powerfull.

oh yea also, the tones i get when i put the keys in the ign. like the fasten seatbelt, or "your lights are on you dummy" those are transmitted through the speaker in the CB.

ahh this is so agrivating!!!!!!!! :cry: :confused2

[seapahn]

For the noise killers: Radioshack, most truck stop stores, car audio stores, electronics stores, online ...

But most often, having a clean power and ground lines direct to battery and frame will do the trick. Also, if your antenna wire is too long, don't coil it up into a tight loop. Keep it as straight as possible and don't run it parallel to power wires for too long.

By the way, are you setting the squelch control on your CB properly? With the squelch turned up, you shouldn't be hearing anything from the CB when there is no actual transmission taking place (that is normal operation).

[jmbrowning]

When I said "Ground close to the radio" I meant, "Ground to the nearest metal object to your CB radio." Tub, roll cage, seat frame whatever. Try grounding the tub, hood, head, frame directly to the batt and grounding the exhaust as suggested by Stu's site.

Running the power through coax sounded like an interesting idea also. Putting capacitors in the fuel pump circuit seemed a bit over the top:tongue:

Personally, I don't mind too much a bit of RF interference. after all, it's not meant to be CD quality it's just a $30 Made-in-China radio.

[JeepJunkie]

first off jmbrowning your right about it being a cheap radio so i guess you get what you pay for. ill try to ground closer to the radio.

Seapahn, i tried running "clean" power and i still got the buzzing. It was on the positive battery terminal and grounded to the side of the body. when you say dont run the antenna wire to close to other wires for too long....how far is too long? a few feet? or less. Also im pretty sure im using the squelch correctly. when its all the way down there is the static and buzzing and i can hear the weaker transmissions from others. when its turned up just to the point where i dont hear any more buzzing its silent untill i get a strong signal, and when i receive that buzzing picks up a little.

So as of right now i really need someone else to test it around here, the signals i have been getting have been from pretty far away(ive heard their location) one of them was from the mile high city....denver not sure how i got that one. another one was from Forest Hill which is about 45 miles or so away. and the only way i could hear these guys was because the squelch was down. Basically i need to test it with someone relatively close, within a few miles. How much range should i be expecting, i know there are a lot of factors. but is it mainly Line of Sight?? so 3 maybe 4 miles away?? thanks for your help so far guys.

[jmbrowning]

You are experiencing "skip". CB runs on the 11 meter band which is essentially High Frequency shortwave.

HF signals skip off the ionosphere, esp when sunspot activity is high. Others even work moon skip where they bounce their signals off of the lunar surface. This requires very specialized antennas and amplifiers (amp use is illegal in CB). I suspect that they won't hear you talking back at them with your five watt rig thru an untuned antenna .

For trail comms under practical communications figure about a mile at best. Less if in gullys and such. In Moab, I was able to radio my wife from the hotel to the City Market which was several blocks, using a stock Rat Shack CB with a tuned antenna. Range goes up if you use SSB, but you won't be able to communicate with the AM guys, which is what most everybody runs.

Try running power through coax cable as this is shielded and should minimize the RF intereference. This seems like an interesting idea and I will probably do this when I get the energy to replace the CB with a decent radio.

If you are really interested in cutting edge technology without static, consider MURS. This is the newest band from the FCC/PRSG and encompasses the old business color-dot bands and is FM, so NO STATIC. Right now there is very little activity on these freqs and there is talk about using some of them for digital data comms such as extending wireless Internet connections for kilometers rather than meters!

If you'd like to borrow my SWR meter and try out the range of your radio, feel free to come on over and we can get your antenna and radio sorted out.

[JeepJunkie]

how do you run the power through the coax cable?? how do you connect it to the power cable on the radio and then to the power source?

i would take you up on coming to test out the radio but arent you in Southern CA?

[NAILER341]

a good ground is key. see that your antenna has a good ground, as does your radio.
some antennas need to have a "strap" which grounds them better. some even have the grounding strap built into the antenna.
wilson makes a nice antenna with strap, and adjustability. i have one of those, and it works very well.

[JeepJunkie]

i think my radio ground is a good one, its grounded to the side of the body and i cleaned the spot before i put it on, also my antenna is a no ground type. how much is that wilson antenna you posted a pic of?? oh yea also would a antenna that isnt NGP eliminate some static?


edit: ooooo i didnt realize that was a link...

[avnative]

Sound like to main prob is the cheap radio, I ran a cobra 29 with a cigarette lighter plug and a mount bolted to my spare tire mount on a new tj, didnt have any prob with alternator feedback.

If you are in the ontario area, there is a great cb shop just south of the TA east truckstop. just south of the RR tracks and east of miliken, Theyve been there along time and have alway done xlnt work on my radio...

[avnative]

One other thing, the only radio antenna I will run is a firestick, Have always used them on the semi and on personal vehicle, Have never had a prob with them....

[JeepJunkie]

ok....im tempted to take this radio back and get another one...could this be my specific radio?? when i first got it somhow i blew the inline fuse....and replaced it with one that could handle a little more....prob wasnt a good idea. i think ill just return mine and get another of the same one. im trying to save my cash for other things to do to the jeep. unfortunately the jeep is sucking down all my monies and at 16 isnt the most abundant of things as im sure thats the same with everyone

[avnative]

Brett, Try using a name brand,(such as cobra or uniden) I have used nothing but those and only one time have had the electrical whine you are having, I took it to a cb shop to have a resistor put in and that fixed it.
You can also go for the firestik antenna, which is fairly cheap and a very good antenna (18 years and well over a million miles I've use them) Honestly, the best place for selection and usually price is a large truckstop like TA or petro as they sell alot and turn em fast..