what is the correct way to set memory channels for Doppler?


Tim L
 


I have read the postings and still not sure  how to set my memory channels to accommodate for doppler on the u/v -v/u Fm sats. I have created memory channels spaced 5KC apart. my question is do I set the xmit and receive both or just xmit frequency? and  do they both increment and decrement in the same direction or do I set them so when the xmit goes up 5 the rec goes down 5? Please help
 
two example's below. what is the correct set up



                       RECEIVE            TRANSMIT


Clint Bradford
 

Neither chart is correct.

On 2M, you really do not have to accommodate for Doppler.

But definitely on the 440 “side” of life.

Transmit on 437.500 - MID 

Transmit BELOW as you acquire - so program …

437.490 AOS-2
437.495 AOS-1
437.500 - MID
437.505 - LOS 1
437.510 - LOS 2

Clint


Steve [AA8AF]
 

Tim,
My understanding is compensation for doppler shift is only needed on the 440 frequency - either for transmitting or receiving on 440.  The 2M frequency can stay the same as the doppler shift is inconsequential.  Here’s a screenshot of a portion of my FT-60 setup I did awhile back (from an RT Systems programmer) showing the center nominal frequency and two steps on either side:


In the case above for SO-50, there’s a channel programmed with the “wakeup tone” (e.g. #102).

Steve
AA8AF

On Jan 18, 2022, at 7:17 PM, Tim L <ptim15@...> wrote:


I have read the postings and still not sure  how to set my memory channels to accommodate for doppler on the u/v -v/u Fm sats. I have created memory channels spaced 5KC apart. my question is do I set the xmit and receive both or just xmit frequency? and  do they both increment and decrement in the same direction or do I set them so when the xmit goes up 5 the rec goes down 5? Please help
 
two example's below. what is the correct set up



                       RECEIVE            TRANSMIT
<dummyfile.0.part>


Tim L
 

Thanks Steve, got it...  Clint Helped alot as well. this is my new config


Clint Bradford
 

If you are outside, reception reports for '92 welcome ... just not working well.

And please only attempt working '91 and '92 when they are in Sunlight!


On Jan 18, 2022, at 6:42 PM, Tim L <ptim15@...> wrote:

Thanks Steve, got it...  Clint Helped alot as well. this is my new config