Antenna question

[reelfinatic]

Hey guys, new here with a question. I have a Uniden PC78LTW CB and twin 4' fiberglass helically wound antennas mounted to my aluminum tool box in pick-up bed. I first had them co-phased and got very high SWR. After doing research I realized they may be to close together so I ran cable from one and left the other as a dummy. Still got very high SWR. Way over 3 on Channel 1 and about 3 on channel 40. From what I read it seems my antenna is too short. Could this be? A 4' antenna too short? I found one web site that listed tons of reasons for high SWR. If I were to test for each of the reasons it take take forever. I am new to CB's so if anyone can help it would be greatly apreciated. And if you need more info on my set up I will try to give it to you. Thanx.

[outerspacehillbilly]

Originally Posted by reelfinatic

Hey guys, new here with a question. I have a Uniden PC78LTW CB and twin 4' fiberglass helically wound antennas mounted to my aluminum tool box in pick-up bed. I first had them co-phased and got very high SWR. After doing research I realized they may be to close together so I ran cable from one and left the other as a dummy. Still got very high SWR. Way over 3 on Channel 1 and about 3 on channel 40. From what I read it seems my antenna is too short. Could this be? A 4' antenna too short? I found one web site that listed tons of reasons for high SWR. If I were to test for each of the reasons it take take forever. I am new to CB's so if anyone can help it would be greatly apreciated. And if you need more info on my set up I will try to give it to you. Thanx.

What brand antenna? What type of vehicle? What type of coax? What type of meter are you checking your swr with? The stock meters in the radios are not reliable at all for the most part. A good external swr meter should be used to check the swr.

[reelfinatic]

The vehicle is a Ford F-150 Supercrew, Tiger Shark Antenna with RG-59 co-phased cable and RG-58 single High SWR on both set-ups.. I am using the internal SWR meter as I do not have an external SWR meter nor know anybody that has one. I also do not know of a cb shop here in central jersey.

[WA4GCH]

A simple meter like this one is all you need ....

[LINK POSTED BY MEMBER] Only Members Can View This Truck Forum Link.

99% of the CB meters work just fine

[Carolina Thunder]

Originally Posted by reelfinatic

The vehicle is a Ford F-150 Supercrew, Tiger Shark Antenna with RG-59 co-phased cable and RG-58 single High SWR on both set-ups.. I am using the internal SWR meter as I do not have an external SWR meter nor know anybody that has one. I also do not know of a cb shop here in central jersey.

you cant go by the internal meter,they are never right. if there is a radio shack close to you then you can get a swr meter from them
for about $30.00.it's not the best but its a lot better than the built in meter!

[outerspacehillbilly]

Originally Posted by reelfinatic

The vehicle is a Ford F-150 Supercrew, Tiger Shark Antenna with RG-59 co-phased cable and RG-58 single High SWR on both set-ups.. I am using the internal SWR meter as I do not have an external SWR meter nor know anybody that has one. I also do not know of a cb shop here in central jersey.

Well for starters that antenna and coax are both junk. Get some good coax like belden RG8 95% shielded or if you want some really good stuff some RG213. Get yourself a good antenna like a wilson 2000 or 5000 or even a 102" whip or choice of several others. The antenna is 95% of your setup. Any of the above antennas and a $30 radio you'll be getting out good and hearing good, or your tiger shark antenna and a $500 radio and you'll still sound like ####! Your choice. Not trying to be harsh just the truth.

[reelfinatic]

I'll get an SWR meter and give it another try. Are twin co-phased antennas on the tool box too close together? That's what I heard. Thanx for the help.

[outerspacehillbilly]

Originally Posted by WA4GCH

99% of the CB meters work just fine

Are you talking internal meters or external. If external then yes but those built in internal meters are pretty much useless on most lower end radios.

[outerspacehillbilly]

Originally Posted by reelfinatic

I'll get an SWR meter and give it another try. Are twin co-phased antennas on the tool box too close together? That's what I heard. Thanx for the help.

Yes. For a proper co-phased setup they should be at least 9 feet apart. A co-phase setup is a pain in the arse to setup properly. Most dual antenna setups are for looks only, one is usually a dummy antenna.

[WA4GCH]

Originally Posted by outerspacehillbilly

Are you talking internal meters or external. If external then yes but those built in internal meters are pretty much useless on most lower end radios.

EXTERNAL .....

I have several I use from my BIRD down to a 40+ year old troughline CB one that works just fine on 2 meters.....