[amsat-bb] Re: AO7 calibration
Bob I have observed this also with AO-7 and VO-52 and to a lesser degree with FO-29 Dave W0DHB -Original Message- From: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] On Behalf Of Bob- W7LRD Sent: Monday, November 18, 2013 10:00 AM To: amsat-bb@amsat.org Subject: [amsat-bb] AO7 calibration Hello...More often than not I have to adjust the up link calibration on satpc32 in order to accurately track the sat. It is not always the same adjustment, it can vary from a few cycles to as much as 2.5 khz. Given AO-7 is a grand old lady, is she just being temperamental, or do I have an issue (operator error). 73 Bob W7LRD ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: AO7 calibration
On 11/18/13, David W0DHB d...@w0dhb.net wrote: Bob I have observed this also with AO-7 and VO-52 and to a lesser degree with FO-29 Dave W0DHB I've had the same issue with Gpredict. 73s Bernhard VA6BMJ @ DO33FL snip ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: AO7 calibration
Hi Bob, There are many reasons why the transponder constant varies somewhat. The temperature of the satellite is somewhat dependent on sun angle, periods of eclipse, etc. This usually results in a slow seasonal variation, most frequently seen in SSB satellites, but also in some cases in the FM birds. In the case of AO-7 there is no battery to stabilize the voltage, so at some (most?) times the 39 year old arrays may not provide enough power for a completely stable output. I recall an article on the subject in the AMSAT Journal, though I don't have it handy. 73s, Alan WA4SCA -Original Message- From: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] On Behalf Of Bob- W7LRD Sent: Monday, November 18, 2013 11:00 AM To: amsat-bb@amsat.org Subject: [amsat-bb] AO7 calibration Hello...More often than not I have to adjust the up link calibration on satpc32 in order to accurately track the sat. It is not always the same adjustment, it can vary from a few cycles to as much as 2.5 khz. Given AO-7 is a grand old lady, is she just being temperamental, or do I have an issue (operator error). 73 Bob W7LRD ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
