[amsat-bb] Why too much uplink power is bad/eggbeater antennas on xmit

Kevin M n4ufo at yahoo.com
Mon Aug 3 03:45:37 UTC 2015


Philip, when I first got back on the birds in 2013, SO-50 was my first attempt ever on an FM bird. I used a HT for receive with a small directional antenna mounted on it and a mere 10 watts to a 2m Squalo. For all intents and purposes, an eggbeater is likely better than my Squalo on transmit gain and my 10 watts was more than enough. Using 50 watts of transmit power is bordering on obscene... using 150 watts by comparison seems downright criminal.

Put it to the OM this way... he's hearing a 1/4 watt transmitter using a 1/4 wave whip from space... some people have talked back to it with 5 watts or less to a rubber duck. Why in the world would it take 50 watts to talk to it, regardless of the antenna?!!!
Sometimes it just takes some common sense and the right point of view to get these things, I guess. =^)

73, Kevin N4UFO

----------------------------My question is two-fold (I still need to follow-up with him). 1) For those
of you successfully using eggbeaters for the uplink (and he is adamant
about not using a yagi, despite my advice that the performance will suffer
quite a bit with eggbeaters), what output power do you typically use? I
think 50 watts into an eggbeater is probably still too much power,
considering 5 watts into an Arrow is usually enough for successful
communications.

2) I know that various power levels are suggested for various gain
antennas, but I'm wondering what the suggested EIRP is for successful - not
ones which would hog the satellite  - uplinks.

Philip N4HF


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