[jegzus]

The problem is your antenna is only 3' long. If you want to be able to receive well and transmit well you need to get a 5' fiberglass antenna or a wilson 2000 trucker.

Also get yourself a SWR meter from radio shack along with a 3 foot jumper cable. Don't trust the SWR meter built into the radio I have never seen one be close to acurate.

The reason you hear the noises when you use the windows is because your power terminals are run to the fuse board in the truck along with everything else. To get rid of that you need to run the power wires right to the battery.

A well tuned cobra 29 will swing to 35 watts, and will receive very well. And a good peak and tune will cost 40-50 dollars, and stay away from truck stop CB shops they are sloppy and usually don't know what they are doing.

[kc0iv]

Originally Posted by jegzus

The problem is your antenna is only 3' long. If you want to be able to receive well and transmit well you need to get a 5' fiberglass antenna or a wilson 2000 trucker.

Also get yourself a SWR meter from radio shack along with a 3 foot jumper cable. Don't trust the SWR meter built into the radio I have never seen one be close to acurate.

The reason you hear the noises when you use the windows is because your power terminals are run to the fuse board in the truck along with everything else. To get rid of that you need to run the power wires right to the battery.

A well tuned cobra 29 will swing to 35 watts, and will receive very well. And a good peak and tune will cost 40-50 dollars, and stay away from truck stop CB shops they are sloppy and usually don't know what they are doing.

Increasing an antenna's length from a 3' to 5' has very little improvement in the signal. It will give a little wider bandwidth. The biggest problem be it a 3' antenna or a 5' antenna the wavelength is still short compared to a 1/4 wavelength ( standard 102") antenna. Both antennas are heavily loaded electrically.

A coax cable should be a 1/2 wavelength (11 meters) to properly connect a VWSR meter. This will reflect the true reading between the antenna and the radio.

If you connect the wire to the battery you should have a fuse connected directly to the battery. A better approach would be to connect a .01mfd 50 volt capacitor directly across the motor terminals.

Since increasing the power from 4 watts to 35 watts amounts to a power gain of 9 db ( or about 1-2 "S" meter readings) I'm not sure you gain much for that 40-50 dollars.

kc0iv

[jegzus]

Originally Posted by kc0iv

Increasing an antenna's length from a 3' to 5' has very little improvement in the signal. It will give a little wider bandwidth. The biggest problem be it a 3' antenna or a 5' antenna the wavelength is still short compared to a 1/4 wavelength ( standard 102") antenna. Both antennas are heavily loaded electrically.

A coax cable should be a 1/2 wavelength (11 meters) to properly connect a VWSR meter. This will reflect the true reading between the antenna and the radio.

If you connect the wire to the battery you should have a fuse connected directly to the battery. A better approach would be to connect a .01mfd 50 volt capacitor directly across the motor terminals.

Since increasing the power from 4 watts to 35 watts amounts to a power gain of 9 db ( or about 1-2 "S" meter readings) I'm not sure you gain much for that 40-50 dollars.

kc0iv

First of all there is a HUGE difference in a 3' and a 5' + antenna and you can never tell me different. The longer antenna's receive and transmit better due to the coil's and wire wrappings to make it equal a 102" antenna.

And yes if you want to be MR.Saftey then put a fuse at the battery along with the fuse at the radio......

And if 1-2 S units is not worth the money then that's fine, run your stock radio and don't cry when everyone is keying on you and you can't talk to any body on channel 19.

And if you want to get really technical the only true way to get an accurate SWR reading is use a bird meter and a 250mw slug to test your reflect that way.

I run 21' of Rg-213 coax in my big truck and my SWR using the bird meter is 1.3:1 on a wilson 2000.

[kc0iv]

Originally Posted by jegzus

First of all there is a HUGE difference in a 3' and a 5' + antenna and you can never tell me different. The longer antenna's receive and transmit better due to the coil's and wire wrappings to make it equal a 102" antenna.

And yes if you want to be MR.Saftey then put a fuse at the battery along with the fuse at the radio......

And if 1-2 S units is not worth the money then that's fine, run your stock radio and don't cry when everyone is keying on you and you can't talk to any body on channel 19.

And if you want to get really technical the only true way to get an accurate SWR reading is use a bird meter and a 250mw slug to test your reflect that way.

I run 21' of Rg-213 coax in my big truck and my SWR using the bird meter is 1.3:1 on a wilson 2000.

Using a older copy of EZNEC software I find the difference of less .0001% between the 3' vs the 5' in near field "E" pattern. On far field "E" pattern shows a increase angle of less than 1 degree. Since we are talking of ground-wave transmission when dealing with CB I don't think you could detect a .0001% change. Even in muli-hop transmission the 1 degree raise in radiation pattern would be only slightly noticeable.

You must have one special setup. Since a Bird 43 with a 250 mW element is a special order item. The lowest Bird 43 element for 27 mhz is 5 watts. A Bird model 5A.

While a VSWR meter such as the Bird will work a better approach is to use a SWR Analyzers. The Bird does not show the reactive component of the signal. The Bird could be showing a 1:1 VSWR but the reactive component could be highly reactive. With the net effect being poor antenna performance. The analyzer will show the true impedance composed of both it's load impedance and it's reactive component.

kc0iv

[unkut2003]

Holy hell, HAHAHA!!! I have NO idea what you guys are talking about... :lol: So in "english", I should go to a local CB shop with my truck and buy an additional '3 antenna for duals? Or, could I just pull the CB from the truck and take itself to the shop and tell em to peak and tune it??? Thanks for all the help too!!!!!

[BigDaddyD]

Not really local to you but on I94 in MI near the umm crap 140 to 160 miles marker there is a shop. I had some work done there when I lived in MI.

[shanhamm]

Originally Posted by BigDaddyD

Not really local to you but on I94 in MI near the umm crap 140 to 160 miles marker there is a shop. I had some work done there when I lived in MI.

Would that be the pilot at the 167 mm?

[kc0iv]

Originally Posted by unkut2003

Holy hell, HAHAHA!!! I have NO idea what you guys are talking about... :lol: So in "english", I should go to a local CB shop with my truck and buy an additional '3 antenna for duals? Or, could I just pull the CB from the truck and take itself to the shop and tell em to peak and tune it??? Thanks for all the help too!!!!!

Adding a second antenna isn't going to solve your problem. attempting to solve a radio system problem via the internet really isn't possible. That being said the first thing is the radio setup correctly?

Common problem(s) when an a radio won't receive is having:
Improper ground *,
Noise Blanker turned on,
RF Gain Control not being set to full on,
Squelch Control not set correctly.

* Many or should I say most truckers mount the antenna on the mirror mounts. While they may be clamped to the the mirror it may not be grounded to the truck chassis. Thereby it is attempting to use the outside of the coax for a ground path. It is important the antenna have a solid ground separate from the coax shield. Poor ground will also affect the transmit signal also.

The effective range a signal can be received varies because of such factors as location, noise level and surrounding obstructions (both near field and far field). VSWR has very little effect on a received signal. Most receivers have enough gain to over come any VSWR problems.

countryhorseman suggested http://]www.firestik.com/Tech_Docs.htm While I don't agree with everything they say it is a pretty good site.

Now a little about "Peak and Tune." It has been my experience very few non-professional shops have the equipment nor the training to properly tune a radio. They turn the screws for maximum deflection not knowing what effects the circuit should being doing or why it does what it does. In all the years I was in the 2 way radio business I found very few radios needed tuning from what the factory settings were, unless part(s) were replaced. I might also add when it comes to the transmitter even fewer have the required license to tune a transmitter.

While a internal VSWR meter leaves alot to be desired most will get you close enough. In fact most CB internal meters use the same circuit used by the cheap external meters.

As I said above attempting to solve a radio problem isn't really possible via the internet.

kc0iv