[By Subject] [By Date] [By Sender [By Thread]
Previous In Time

Next in Time

From: f6dro@mail.jovenet.fr
Subject: re: Dayton Johnson's 1296 double rhombic.
Date: Fri, 29 Nov 1996 22:27:08 +0100
At 10:45 29/11/1996 -0600, you wrote:
>Bernie nuls wrote:
>> Dayton Johnson's 1296 double rhombic.
>> Date:
>> 29 Nov 1996 10:08:20 -0600
>> From:
>> bad@uhf.wireless.net
>> To:
>> Geraldj
>>On page 90 of December QST is a picture of Dayton Johnson and his award
>>winning 1296 MHz. double rhombic. Does anyone know where he got the
>>from or wether he designed/optimized it himself for 1296?
>>I'd very much like to copy his design and build something similar for
>>(about the same gain, but with much lower visual impact than my 33
>>element loop yagi).
>>Bernie nu1s
>Hi, I don't know about the 23cm design but I do remember seeing a 70cm double rhombic described in 73's magazine around 1978 (+/- 1 year).This one should be the inspiration source for the 23cm antenna.Just one word:gain is OK to win gain contests but more important is G/T.For Rhombics G/T is very poor due to low efficiency (loss in terminating resistor),the very poor efficiency is OK on HF,but not on VHF/UHF.Noise temperature of the antenna is very high.So if you want a good antenna built something else. 73's Dom

------ Submissions: vhf@w6yx.stanford.edu Subscription/removal requests: vhf-request@w6yx.stanford.edu Human list administrator: vhf-approval@w6yx.stanford.edu