AO-85: Tone or no Tone for SSTV
two questions:
According to Amsat website, 67Hz tone is required for a couple of seconds to activate repeater.
Once the repeater is activated, does it still require the tone every couple of minutes to stay on, or does it only start the timer after normal ("un-toned") activity stops?
Will constantly sending the tone during SSTV Tx mess with the SSTV Rx? I'm planning on eventually trying my own image, and want to be sure I don't waste 36 seconds of valuable airtime.
-Roy K3RLD
Roy,
AMSAT recommends always sending the tone on AO-85. If it doesn't hear the tone for two minutes, the repeater will turn off.
The 67 Hz tone is well below the SSTV signal's tones and will not interfere with signal transmission. The lowest tone used in a Robot36 transmission is 1100 Hz and the highest tone is 2300 Hz (with the image transmission occurring primarly between 1500 and 2300 Hz).
73,
Paul, N8HM
On Wed, Aug 30, 2017 at 9:11 AM, Roy Dean [email protected] wrote:
two questions:
According to Amsat website, 67Hz tone is required for a couple of seconds to activate repeater.
Once the repeater is activated, does it still require the tone every couple of minutes to stay on, or does it only start the timer after normal ("un-toned") activity stops?
Will constantly sending the tone during SSTV Tx mess with the SSTV Rx? I'm planning on eventually trying my own image, and want to be sure I don't waste 36 seconds of valuable airtime.
-Roy K3RLD _______________________________________________ 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: http://www.amsat.org/mailman/listinfo/amsat-bb
On 8/30/2017 08:16, Paul Stoetzer wrote:
AMSAT recommends always sending the tone on AO-85. If it doesn't hear the tone for two minutes, the repeater will turn off.
Correction, it's one minute.
Jerry Buxton, NØJY
Roy
What's the audio bandwidth of you sstv ?
Andrew
Sent from my iPhone
On 30 Aug 2017, at 11:11 pm, Roy Dean [email protected] wrote:
two questions:
According to Amsat website, 67Hz tone is required for a couple of seconds to activate repeater.
Once the repeater is activated, does it still require the tone every couple of minutes to stay on, or does it only start the timer after normal ("un-toned") activity stops?
Will constantly sending the tone during SSTV Tx mess with the SSTV Rx? I'm planning on eventually trying my own image, and want to be sure I don't waste 36 seconds of valuable airtime.
-Roy K3RLD _______________________________________________ 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: http://www.amsat.org/mailman/listinfo/amsat-bb
participants (4)
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Andrew Rich -
Jerry Buxton -
Paul Stoetzer -
Roy Dean