Diamond Discone D130J and CB channels

[chazcarly]

Is there anything I can do to improve my Diamond discone to pick up CB Channel 19, 27.185 I work next to the Interstate and with and old mag base mobile Larson tri band on top of my toolbox it comes in fine, but when I'm plugged in to the New discone on the roof of the building, nothing. For everything else the Diamond is working great. I thought I read something that the center radial of the mass is the low band part of the antenna and trimming that might help, if that is true how do you know how much to cut off?

This is on my 996P2. with RG8

Thanks for your help.

 

[Dog]

Is there anything I can do to improve my Diamond discone to pick up CB Channel 19, 27.185 I work next to the Interstate and with and old mag base mobile Larson tri band on top of my toolbox it comes in fine, but when I'm plugged in to the New discone on the roof of the building, nothing. For everything else the Diamond is working great. I thought I read something that the center radial of the mass is the low band part of the antenna and trimming that might help, if that is true how do you know how much to cut off?

This is on my 996P2. with RG8

Thanks for your help.

"Trimming" is used to "tune" an antenna. It done for transmitting. You need a transmitter and SWR meter or power watt meter to know how much to trim.

 

[mmckenna]

Trimming would help, even if not transmitting.

However, the whip on those antennas is usually tuned around 50MHz, and you'd need to lengthen it quite a bit to make it resonate at 27MHz.
Add in there's a lack of suitable ground plane to make it work right.

These discones are not very good at CB frequencies, even though they may advertise frequency capability down to 25MHz.

If you want decent CB performance, get an old CB antenna and drop it on a large metal ground plane.

 

[Brales60]

I pick up channel 19 with my Omni X about 20' up. I'm about 3-4 miles from I-75.

 

[chazcarly]

Thanks for all the answers.
How about two antennas with a splitter? The Larson works fine for the CB. I just don't know about if you can use a splitter or if you can what one to get.

 

[mmckenna]

Depends on exactly what you are planning to do with the splitter?
Are you trying to combine two antennas to one radio?
-or-
Use one antenna for two radios?

 

[chazcarly]

Yes one radio,my 996p2

 

[Dog]

Depends on exactly what you are planning to do with the splitter?
Are you trying to combine two antennas to one radio?
-or-
Use one antenna for two radios?

"splitters" are cheap. It wouldn't cost much to try it out. A lot of variables. If it doesn't work as you planned you can try a multicoupler but that is a lot more expensive option.

 

[mmckenna]

Yes one radio,my 996p2

One radio connected to two antennas?

Yes, however you cannot just "T" the two together. That can work, or it can totally cancel out any gains. You need to use a diplexer. It's a frequency/band selective combiner. The would have a common port you connect your radio to. There would be two (or more) ports you would connect the antennas to.

You would need to have a diplexer that handled the frequencies you wanted.
There isn't a huge selection, so finding one that will do what you want may be a challenge.

 

[mmckenna]

Something like this might do what you want:

Comet Antennas CF-360B Comet Duplexers | DX Engineering

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