SatPC32 - New Program Feature - Doppler
Erich DK1TB has again implemented another great feature into SatPC32 V12.8b by means of a "patch" file. You can find it in the "downloads" link on his website, www.dk1tb.de Scroll down to Section 7, Patches.
I often hear others talk about meeting someone, usually a long distance new grid square, on a certain frequency. Since doppler is always in play, telling someone you will be on 435.845 is meaningless unless you are both in the approximate same location. If the other station is at LOS and you are at AOS, your dial readings could be 15Khz apart. It's a great way to miss a 60 second window.
The trick here is to use the same point of reference. That reference would be the frequency you are on at the satellite receiver. The whole idea of doppler correction is to be at a constant frequency within the satellite receiver passband. To do that you have to adjust your uplink frequency constantly. And you have to adjust your downlink frequency to continue to hear yourself or someone else using full doppler correction.
Erich has now added the option of seeing the frequency you are on at the satellite receiver. This is a common frame of reference so if you tell someone you'll be on 435.845 at the satellite, they can be on that same frequency even though your terrestrial dial frequencies will be much different. Just adjust your receiver or use the up/down buttons in SatPC32 to set your frequency shown in the "Sat" window. That frequency will remain constant as your uplink and downlink are controlled by SatPC32.
If you haven't managed to interface your radio with SatPC32, this is just another reason to do so. Staying at a constant frequency at the satellite allows many stations to share the bird without drifting into each other. And being able to know exactly where you are in the passband without doing the calculation in your head gives you more time to concentrate on making a successful QSO! Rumor has it that even a certain Maritime Mobile will soon be controlling his radio with SatPC32.
73, John K8YSE
Hi Erich, DK1TB
Congratulations for your new implementation into SatPC32 V12.8b It is really a great job seeing the frequency we are on at the satellite receiver !
73" de
i8CVS Domenico
----- Original Message ----- From: "John Papay" john@papays.com To: amsat-bb@amsat.org Sent: Friday, March 23, 2012 1:20 AM Subject: [amsat-bb] SatPC32 - New Program Feature - Doppler
Erich DK1TB has again implemented another great feature into SatPC32 V12.8b by means of a "patch" file. You can find it in the "downloads" link on his website, www.dk1tb.de Scroll down to Section 7, Patches.
I often hear others talk about meeting someone, usually a long distance new grid square, on a certain frequency. Since doppler is always in play, telling someone you will be on 435.845 is meaningless unless you are both in the approximate same location. If the other station is at LOS and you are at AOS, your dial readings could be 15Khz apart. It's a great way to miss a 60 second window.
The trick here is to use the same point of reference. That reference would be the frequency you are on at the satellite receiver. The whole idea of doppler correction is to be at a constant frequency within the satellite receiver passband. To do that you have to adjust your uplink frequency constantly. And you have to adjust your downlink frequency to continue to hear yourself or someone else using full doppler correction.
Erich has now added the option of seeing the frequency you are on at the satellite receiver. This is a common frame of reference so if you tell someone you'll be on 435.845 at the satellite, they can be on that same frequency even though your terrestrial dial frequencies will be much different. Just adjust your receiver or use the up/down buttons in
SatPC32
to set your frequency shown in the "Sat" window. That frequency will
remain
constant as your uplink and downlink are controlled by SatPC32.
If you haven't managed to interface your radio with SatPC32, this is just another reason to do so. Staying at a constant frequency at the satellite allows many stations to share the bird without drifting into each other. And being able to know exactly where you are in the passband without doing the calculation in your head gives you more time to concentrate on making a successful QSO! Rumor has it that even a certain Maritime Mobile will soon be controlling his radio with SatPC32.
73, John K8YSE
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
John,
Thanks for mentioning this. I had missed his update. This makes SATPC32 unique in providing this support.
There is an article in the July/August 2010 issue of the AMSAT Journal called "Bringing the One True Rule of Doppler Tuning into the 21st Century." It explains in some detail the rational for doing this. If someone wishes a copy, please contact me OFF LIST and I will send you a PDF.
73s,
Alan WA4SCA
-----Original Message----- From: amsat-bb-bounces@amsat.org [mailto:amsat-bb-bounces@amsat.org] On Behalf Of John Papay Sent: Thursday, March 22, 2012 7:21 PM To: amsat-bb@amsat.org Subject: [amsat-bb] SatPC32 - New Program Feature - Doppler
Erich DK1TB has again implemented another great feature into SatPC32 V12.8b by means of a "patch" file. You can find it in the "downloads" link on his website, www.dk1tb.de Scroll down to Section 7, Patches.
I often hear others talk about meeting someone, usually a long distance new grid square, on a certain frequency. Since doppler is always in play, telling someone you will be on 435.845 is meaningless unless you are both in the approximate same location. If the other station is at LOS and you are at AOS, your dial readings could be 15Khz apart. It's a great way to miss a 60 second window.
The trick here is to use the same point of reference. That reference would be the frequency you are on at the satellite receiver. The whole idea of doppler correction is to be at a constant frequency within the satellite receiver passband. To do that you have to adjust your uplink frequency constantly. And you have to adjust your downlink frequency to continue to hear yourself or someone else using full doppler correction.
Erich has now added the option of seeing the frequency you are on at the satellite receiver. This is a common frame of reference so if you tell someone you'll be on 435.845 at the satellite, they can be on that same frequency even though your terrestrial dial frequencies will be much different. Just adjust your receiver or use the up/down buttons in SatPC32 to set your frequency shown in the "Sat" window. That frequency will remain constant as your uplink and downlink are controlled by SatPC32.
If you haven't managed to interface your radio with SatPC32, this is just another reason to do so. Staying at a constant frequency at the satellite allows many stations to share the bird without drifting into each other. And being able to know exactly where you are in the passband without doing the calculation in your head gives you more time to concentrate on making a successful QSO! Rumor has it that even a certain Maritime Mobile will soon be controlling his radio with SatPC32.
73, John K8YSE
_______________________________________________ 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
participants (3)
-
Alan P. Biddle -
i8cvs -
John Papay