View Full Version : Peak and Tune

12-15-2016, 03:43 AM
I have heard mention in several articles that sometimes the radio might need some peaking and tuning. I have a
Cobra 29 LX 40-Channel CB RadioAnd as i rarely use it except when way off road in a group, and have never really been able to send out. I would like a suggestion if possible of either a shop to send it to, or to buy a new unit that it is operating at max.

Depending on the group, it's either FRS, CB or ham

12-15-2016, 06:42 AM
The radio most likely isn't your issue. It's most likely your antenna setup and the terrain. What type of antenna do you have and how long is it. Also where is it placed. Antenna systems are often overlooked. And even with a peak and tune it won't help if the antenna setup isn't right. JMHO's.
All a peak and tune is that a tech goes in and makes sure the radio is receiving and transmitting on the same frequency and the right one, and also he will turn the modulation and AM power up and making sure it is transmitting a clean signal. Not all techs do the last thing i listed as they don't have the correct equipment. So if you do decide to send it out, send it to a reputable tech. Doug's Custom CB shop. Fine Tune, Mikes Radio Repair, Key CB, Bells cb shop in FL. Those are some good ones. But as I said, look into your antenna setup first and read up on how a short antenna versus a full 1/4 wave whip, which is about 108" total, as most use a 4-6" spring and a 102" whip. Also you need metal under the antenna. They do make ones that can work without a lot of metal under them, Firestick antennas have some like this. Thing is to get the tallest one you can possible get. 6ft one if they have it. Or a 5ft one. The closer to 108" physically the better. JMHO's. Hope this helps some. Have a good day.

Squirrel Slayer
12-18-2016, 01:38 PM
I was using a Wilson 1000 magnet mount and it worked really well, but I kept knocking it over. Now I'm using a
MFJ-1966 108" SS whip and no spring with 18' coax mounted off the spare tire rack . It works better than the Wilson by a long shot . The SWR is 1.2 on both ch 1 and ch 40. It get out like a boss...

12-18-2016, 02:25 PM
Yep. Mag mount antenna are not truly made for permanent installation. And the closer to 108" or near that is going to be best as far as height. Physical length, not what the box or package says either. There is no compromise for length IMO. Get the antenna setup right and you will find that an amp might not be needed. But for a small amp that works good for what it is, the RM Italy KL203P. Spend more and get a TNT 350HD for more power and a better overall amp. Again without a proper antenna setup you are just pissing in the wind. Sorry not trying to be harsh just realistic. Hope this helps. Good day.

12-18-2016, 09:26 PM
I have several Wilsons and Firesticks, but I like the idea of the 108" whip. Will hunt for a place that sells them in the SF Bay area or wait until I get moved to Oregon. The nice thing about the whip is you can lay it down when not in use. During the early 80"s when living in Nevada, everyone had a cb and it was funny to listen to the "CB Cops" that would try to chase after some one transmitting with more power than allowed. Where I would be using it, I doubt and CB cops are going to go after me because they would have to be willing to go 30 - 40 miles off road. I will use my ham setup for range, but like i said, not everyone has a ham radio or license, and so easiest is FRS then CB then Ham. When I connect to my truck, I have a bracket in the back that is bolted to the metal if the frame, is there any special connection process or just tie it down and run my coax

Squirrel Slayer
12-18-2016, 09:46 PM

is where I got mine ,the shipping hurts more than the antenna ...

12-19-2016, 01:03 AM
Thanks, cheaper than this one:


12-19-2016, 06:30 AM
Make sure you install it properly and have a good ground plane below it. Metal under the antenna will make it work at its best. The more metal as in like a roof of a vehicle is what is really needed. The larger the vehicle the better as well. But you can make them work without a lot of metal not saying you can't. They just won't be as efficient.
Use good coax, if the connector is outside in the weather, make sure you weather proof if correctly and well. Also you can use NO-OX on all connection points and make sure that it's bare metal to metal contact with the mount and such. Again, use good coax, not the cheap truck stop stuff either. It will pay in the long run. These are JMHO's. Good day