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*Subject*: Re: [amsat-bb] FO-29 Freq*From*: "John P. Toscano" <tosca005@xxxxxxxxxx>*Date*: Mon, 11 Dec 2000 13:25:35 -0600

Robert Jewell wrote: > Translation Equation: > > downlink = 581.800- uplink freq (plus or minus doppler). > > NON inverting. Robert, why do you say NON inverting? It most certainly *IS* an inverting transponder. That's how I have it programmed into my FT-847, with LSB on the uplink and USB on the downlink, inverted tracking, and once the Doppler is factored in, I can tune up and down the passband with the main tuning knob and the uplink and downlink stay correctly adjusted with respect to one another. Even your equation shows it. As the uplink increases, the downlink decreases, and vice versa. For a NON-inverting transponder, the equation would be in the form of downlink = offset + uplink so that as the uplink increases, the downlink also increases. The basic frequencies for either FO-20 or FO-29 in JA mode would thus be, before Doppler correction: Uplink 145.90 (bottom), 145.95 (mid), 146.00 (top) Downlink 435.90, 435.85, 435.80 There was an email message announcing an updated "Fuji Transponder Map" on this list within the week, but I don't have the URL handy now. This "map" showed more precise sets of numbers for the uplinks and downlinks on the two Fuji birds that are slightly different than the short table above, due to a drift in the working frequencies of the transponders on the two spacecraft over the years. So there are actually two equations, one for FO-20, and one for FO-29, that are slightly different than the one you listed above. John (KBØZEV) ---- Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA. To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org

**References**:**FO-29 Freq***From:*Robert Jewell

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