BB7V question

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k1agh

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I just got a BB7V antenna and was wondering if I attached a 2 meter j pole antenna to the mast would it affect anything? I wouldn't be attaching it to the antenna just the mast I have to supply to mount it.
 

prcguy

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If you put the J-pole on an arm to get it away from the mast it should work ok. A 2m J-pole might even work better on HF than the HF antenna you chose....
prcguy

I just got a BB7V antenna and was wondering if I attached a 2 meter j pole antenna to the mast would it affect anything? I wouldn't be attaching it to the antenna just the mast I have to supply to mount it.
 

SCPD

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.................Looking at the BB7 -- it would probably be fine to mount a J-pole beneath the active element. I'd keep it clear of anything that addition would detune. Personally I don't think much of J-poles- they are mechanically awkward, for one thing -- if you are looking to mount anything to the side of that BB7's support, I'd suggest a simple half wave dipole. For that matter, if its possible, I'd make your VHF antenna separate from this setup. There is enuff RF going on right there at the HF antenna to be mixing in something else at so close a proximity. But all this is just one person's personal preferences- a J-pole properly done should be fine :)
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....................CF
 

k1agh

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Thanks for the tips. I wont be using HF and 2 meter at the same time.
A 2m J-pole might even work better on HF than the HF antenna you chose....
prcguy--what do you mean by this?
 

prcguy

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The BB7 is Diamonds answer to the Comet CHA-250B, which is an end fed pipe with about a 6:1 balun at the end and no ground radials or counterpoise. On 80 through 40m its a dreadful performer and a tuned 7ft Hamstick on a small car will put out a bigger signal. On 20 through 10m people boast about making contacts on them but most any type of antenna would put out a bigger signal, including a Hamstick on a car.

I wish the mfrs of these things would put information in their advertising so people would know what to expect. Instead of simply advertising "The new BB7V multiband vertical antenna provides coverage from 2 MHz to 30 MHz without radials and requires the use of a tuner", they should also add something like "Its typically -25dB down from a dipole on 80m, 20dB down from a dipole on 40m and only a small fraction of your signal will radiate on other bands. And that is dependent on your length of coax, which by the way will also radiate".

I know lots of people don't have space for a wire antenna stretched out across the property or lots of ground radials, but this particular type of antenna is a complete dog and there are much better performing antennas of similar size that will cover 40 through 10m and some larger ones that will work ok on 80m. You will find this out by visiting other hamsters in your town and watching them making tons of contacts that you cannot with the same amount of power and the only difference will be the antenna.
prcguy


Thanks for the tips. I wont be using HF and 2 meter at the same time.
A 2m J-pole might even work better on HF than the HF antenna you chose....
prcguy--what do you mean by this?
 
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