CB/VHF Conflicting

[Ckeith11]

I'm thinking about installing a base station at my house, and was playing with the idea of putting a VHF antenna up with a CB. I live right next to the coast, and I like to listen to the guys fishing talk on the radio(I also fish and like to get the fishing reports). I was thinking about mounting a regular 10 foot boat VHF antenna on my chimney, but I have two questions about the CB,

-Would a 102 whip work if its up 20+ feet and I'm 1/2 mile or so from an overpass on flat ground?
-Would the CB and VHF signals conflict even though they are on different frequencies?
I have several VHF laying around, so a VHF isn't a problem, but would pulling my mobile out of my truck serve fine for short distance talking from my base?

Thanks,
-Curt

[316]

No they will not conflict.
Now if you are wanting to run more power than 30 or so watts I would turn the VHF off, so that you do not destroy the radio.
Also I be sure that you ground both of them as well as possible.

[linx]

They work great together.

The only time I get any issues is when I have both radios on, and key my 2 meter radio. It is a 50w radio and fills my CB with static. Vise versa, I get now issues with keying my CB and going into my VHF, and I'm running a heck of a lot more watts.

My antennas on my pickup truck are a couple inches apart

As far as the 102" whip. I guess you could get out cheap like that. I've seen it done. If it was a permanent fixture though, you may as well buy an antron 99 or something though. I would imagine in the wind, the 102" would lose SWR just like it does in a mobile, and with you being on the coast, the wind probably never stops.

[KI4MSJ]

You want to mount the two antennas as far apart as possible. If they are to close they will interfere with each other. They are so far apart in frequency that if spaced properly, they will not harm each other. As far as the 102" whip, there are some post in here about that very same question. I would suggest a base antenna or at the very least make yourself four radials 1/2 wave length to the frequency you want to operate at. And make sure you ground the antennas well. Good luck

[Ckeith11]

Alright thanks guys, I'm going to look at an A-99. As far as pulling my Uniden out of my truck and using that, how well will that work. Someone on here estimated its doing 20-30 PEP, which I believe means peak envelope power. Will this cut it?

[80 meter man]

I run CB and VHF all day together among others no problem. Like the other guy said turn of the the radio your not transmitting on if you hear heavy static on it. If you don't hear any interference you will be fine leaving both radios on. I do and have never had a problem. I only have to run 15 watts VHF and less than 100 for HF and they never bother each other.

A general rule when mounting antennas is mount them at minimum one wave length apart. Any closer they will reflect off each other. The antenna for the longer wave length will be affected more than the shorter wave length.

[dud muck]

If both the CB and VHF antennas are verticals, then some vertical separation will help, one higher than the other.
If your limited in horizontal separation, a few ferrites on the coax feeding the higher antenna can help.

A low-pass filter on the CB will help. CB transmit harmonics go into VHF. The filter also works on receive, keeping VHF from hitting your CB receive.

If you had the extreme case where you wanted to run big watts on the CB, and use the VHF at the same time, that gets a bit brutal. Might need a high-pass filter on the VHF radio for that.