[amsat-bb] Re: 25 watt Moonbounce
hbottiki at gmx.de
Sat Feb 2 12:53:35 PST 2008
I am using a homebrew single 6 el. Yagi (DK7ZB design 10.15dBd gain) on the
terrace of my house (approx 8ft above ground on a tripod))for "QRP EME"
operations regularly. I am running about 90-100 Watt into this antenna
(approx 1 KW ERP). This is real QRP for EME standards.
Usually Gary KB8RQ always comes back on my first calls (even without prior
announcement of my call in one of the usual EME internet chat rooms).
Thus, I would guess that it would even work with much less power (I just
never tried it)...so it seems "normal practice" at least with big gun
stations of the size of KB8RQ, W5UN, etc.
I would even say if he could work KB8RQ with 25w he should give RN6BN a try
with only 10-15w (he uses most likely the largest private array on earth
since he has recently expanded it). The smallest station he ever worked via
OSCAR 0 was a 4 el. yagi with 40W. I am sure you can even decode him on a
dipole+preamp, since he has exorbitant strong signals (even compared to
other big guns).
RX is generally not the problem: I can copy 2 and 4 yagi stations very
frequently. I even copied some single longyagi (6 lambda boom length)
stations with my tiny antenna in the past a few times. The only problem is
the return path where you simply would need more HF power.
In total I have already worked about 8 stations (the smallest were 8 yagi
group stations) and had more than 15 QSOs with my tiny setup during the past
This is of course only possible with the help of WSJT software and JT65
mode, hi !!! Otherwise we would still be stuck in EME stone age.
73 de Oscar DJ0MY
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