A buddy of mine just installed MacDoppler
It seems to work great but he sent me a video that doesn't make sense to me.
It is controlling his radio changing freqs as needed to account for Doppler. BUT... I have never seen this before.
the 144 band was changing one way in freq and the 440 band the other way. Huh? That doesn't seem right in my head.
anyone care to maybe explain whats happening?
Joe WB9SBD
He must have been tuning while he was looking at an inverting linear transponder. That is, the downlink frequency goes up while the downlin frequency goes down as you tune across the passband. The doppler correction will always be in the same direction.
On Fri, Jul 10, 2020 at 7:32 PM Joe via AMSAT-BB [email protected] wrote:
A buddy of mine just installed MacDoppler
It seems to work great but he sent me a video that doesn't make sense to me.
It is controlling his radio changing freqs as needed to account for Doppler. BUT... I have never seen this before.
the 144 band was changing one way in freq and the 440 band the other way. Huh? That doesn't seem right in my head.
anyone care to maybe explain whats happening?
Joe WB9SBD
Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
Nope he wasn't touching anything the Mac Doppler was doing it all all by itself.
Joe WB9SBD
On 7/10/2020 6:42 PM, Burns Fisher via AMSAT-BB wrote:
He must have been tuning while he was looking at an inverting linear transponder. That is, the downlink frequency goes up while the downlin frequency goes down as you tune across the passband. The doppler correction will always be in the same direction.
On Fri, Jul 10, 2020 at 7:32 PM Joe via AMSAT-BB [email protected] wrote:
A buddy of mine just installed MacDoppler
It seems to work great but he sent me a video that doesn't make sense to me.
It is controlling his radio changing freqs as needed to account for Doppler. BUT... I have never seen this before.
the 144 band was changing one way in freq and the 440 band the other way. Huh? That doesn't seem right in my head.
anyone care to maybe explain whats happening?
Joe WB9SBD
Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
Hi Joe, sounds right. In the shack—Downlink Doppler goes down, uplink Doppler goes up. Think I’m saying that right!
Mark N8MH
On Fri, Jul 10, 2020 at 7:31 PM Joe via AMSAT-BB [email protected] wrote:
A buddy of mine just installed MacDoppler
It seems to work great but he sent me a video that doesn't make sense to me.
It is controlling his radio changing freqs as needed to account for Doppler. BUT... I have never seen this before.
the 144 band was changing one way in freq and the 440 band the other way. Huh? That doesn't seem right in my head.
anyone care to maybe explain whats happening?
Joe WB9SBD
Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
participants (3)
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Burns Fisher -
Joe -
Mark L. Hammond