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Re: FO29/FO20 blues



on 9/5/00 5:52 AM, jim at jmadden@seanet.com wrote:

> However, when I try to transmit in the middle of the band (lsb on
> 145.95) I hear nothing on receive at 435.85.

It's not an exact match.  You have doppler effects to account for.  You
probably made it in, but your resulting downlink may be above or below the
"nominal" frequency.  If the satellite is coming toward you, your uplink
frequency will look higher at the satellite than 145.95 so you will have a
lower downlink frequency at the bird than 435.85.  However, there is a
doppler shift in the downlink to you as well which results in the frequency
going up as far as  you are concerned.  If doppler were the same on both
bands, it would be a wash, but the effects are more pronounced on 70 cm so
my bet is you would have to tune higher than 435.85 to hear yourself.


Move your RX around while transmitting a CW tone.  You should hear yourself.

73,

Jon
NA9D

-------------------------------------
Jon Ogden
NA9D (ex: KE9NA)

Member:  ARRL, AMSAT, DXCC, NRA

http://www.qsl.net/ke9na

"A life lived in fear is a life half lived."

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