[amsat-bb] Re: yagi design (DK7ZB)

[Henk, PA3GUO]

Hi Bert !

DK7ZB antennas have a relative small bandwidth. What I did was to
make all elements a bit shorter, in order to go from 144.5 to 145.8 MHz.
EME stations seem to like the design. Fewer elements compared to other
designs. Total boom length is still comparable though.

I have built an 145 MHz DK7ZB, and have also done some measurements.
Have a look at: http://www.pa3guo.com/dk7zb.html (pictures & measuments)

Together with the TS2000 my 2x6 elements DK7ZB does all I need for sats.
Used it for RAFT, ANDE and PCSAT-1 commanding.
Also enough to relative 'strong' on ISS (with the 100W from the TS2000)

Henk, PA3GUO
http://www.pa3guo.com

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Hi all,

For the 2m version, I took the following design of DK7ZB as a start:
http://www.qsl.net/dk7zb/start1.htm -> 144MHz yasis -> 6 El-28-Ohm (2m60).
Because I want to tune this antenna to the upper side of the 2m band (I  had
145.800MHz as center frequency in mind), I entered the data of this yagi in
MMANA GAL, a free NEC program (http://mmhamsoft.amateur-radio.ca/mmana/).
After Calculation, i got totally diferent results as on the DK7ZB website.

Please find the MMANA file as an attachment on this mail. What am i doing
wrong?

73,

Bert - ON4DMD