Pete, I’ve found the best way to A/B antennas in real time is to listen on one
of the hundreds of online Kiwi SDRs …. You can flip from one antenna to the
other instantly and the difference is readily apparent. RBN can never be A/B ‘d
instantly.
Steve VE7SL
----- Original Message -----
This would have been more helpful to Ignacy before the second antenna
went up, but taking off from Stan's question ... if you want to get a
quick quantitative comparison between two transmitting antennas, you can
use the Reverse Beacon Network. Go to
https://reversebeacon.net/main.php. ; Transmit a CQ or test (CQ or TEST
at least twice, and your callsign 3-4 times) and note the spots that
result. QSY at least 0.3 KHz and repeat. You should see spots from
some of the same stations, and you can readily tell (in dB) which
antenna was stronger. You can do the same trick to compare receiving
antennas, without QSYing, but you must wait 10 minutes before the system
will accept a second spot of the same station from you.
73, Pete N4ZR
On 1/18/2023 11:31 AM, Stan Stockton wrote:
> Ignacy,
>
> Is your thought that you are a few dB weaker based on sone kind of A-B test
> of the two antenna setups or just that you feel weaker?
>
> 73…Stan, K5GO
>
> Sent from my iPhone
>
>> On Jan 17, 2023, at 9:44 PM, Ignacy Misztal<no9e@arrl.net> wrote:
>>
>> I have a 100 ft tower with jk mid tri 40 on top. When shunt fed, it was
>> pretty competitive on 160. Recently the antenna seems to be a few db
>> weaker. The only change was adding another beam at 60ft. Could it have had
>> an impact? Adding the beam only marginally affected the match.
>>
>> Ignacy NO9E
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