This is a great thread.
Well, I am going to continue with full doppler and just resolve myself to tuning in some people that are not quite there yet. As a lot, I would think adding computer control to handle full doppler would not be that big a deal nowadays as most of the programs support it. I am not telling you how to spend your money though. The big test will be at Field Day when I am using full doppler and listening to everyone do the doppler-shuffle. :)
See you on the air as W4TA from Field Day but NEVER on an FM bird.
73,
Tom Schaefer, NY4I ny4i@arrl.net EL88pb Monitoring EchoLink node KJ4FEC-L 489389 DSTAR Capable APRS: NY4I-15
On Jun 9, 2011, at 1:19 PM, David Palmer KB5WIA wrote:
Jerry's correct. If you only adjust your transmit frequency, such that your receive frequency appears to stay the same -- then you're automatically correcting for your own downlink doppler, but not for anyone elses. Other hams in the footprint will still have to chase you. The only way to stick with the "one true rule" is to adjust *both* uplink and downlink during the pass.
That being said, adjusting the higher (UHF) transmit frequency on VO-52 and AO-07 only (ie. manual control) will get you pretty close, and you won't drift a whole lot. I hear plenty of hams doing this, as long as there are just one or a two QSO's going on, they don't drift into each other very often.
73 de Dave KB5WIA / CM88 SatPC32 with 2xFT817ND
On Thu, Jun 9, 2011 at 7:35 AM, n0jy@lavabit.com wrote:
OK my brain may be playing tricks, but if you vary only your transmit frequency such that you always hear yourself on the same downlink frequency, isn't it true that the other station may not necessarily be hearing you on the same downlink frequency and is chasing you anyway? Your doppler is +5kHz (for example) on the receive, the bird is just about to pass overhead of me though so my receive ferquency goes rapidly from +2kHz to -5kHz, your transmit tuning has no relation at all to what frequency I am listening on. Then the bird goes past you and you suddenly switch down 5kHz, so I have to follow you on my receive.
Or am I nuts? (Quite possible, come see where I work and you will understand!)
Jerry NØJY
I always varied the transmit.
This way the person I'm talking to as well as any other listeners are all on the same freq listening.
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