This came up on Twitter recently. [1] When I first started using SO-50 I assumed once the transponder was turned on with the 74.4 Hz tone it would stay on as long as it was being used (people are uplinking with a 67 HZ tone), but in fact it turns off every 10 minutes regardless of activity.
If you ever hear it go silent in the middle of a busy pass try sending a 74.4 hz tone to reset the timer/turn the transponder back on.
73, John Brier KG4AKV
John,
I have noticed that over the last couple years. Have had to turn it back on during several passes. I never remember having to do that in the early years of the sat. Maybe it is showing its age.
73, Scott, KA7FVV Director - KBARA. kbara.org Alternate Board of Director - AMSAT amsat.org Co-Owner WA7DRE 443.525 System Fusion Repeater Co-Owner KA7FVV 147.320 KBARA Repeater ka7fvv.net
On Mar 25, 2019, at 08:15, John Brier [email protected] wrote:
This came up on Twitter recently. [1] When I first started using SO-50 I assumed once the transponder was turned on with the 74.4 Hz tone it would stay on as long as it was being used (people are uplinking with a 67 HZ tone), but in fact it turns off every 10 minutes regardless of activity.
If you ever hear it go silent in the middle of a busy pass try sending a 74.4 hz tone to reset the timer/turn the transponder back on.
73, John Brier KG4AKV
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
The 10-minute timer is documented here: https://www.amsat.org/two-way-satellites/so-50-satellite-information/ although I can see you might assume that the 10 minutes means "10 minutes with no use".
But I was always told "don't worry about the 10 minute timer--someone will have triggered it". Maybe the "someones" who used to trigger it frequently are using it less than they used to :-)
Burns
On Mon, Mar 25, 2019 at 2:03 PM Scott via AMSAT-BB [email protected] wrote:
John,
I have noticed that over the last couple years. Have had to turn it back on during several passes. I never remember having to do that in the early years of the sat. Maybe it is showing its age.
73, Scott, KA7FVV Director - KBARA. kbara.org Alternate Board of Director - AMSAT amsat.org Co-Owner WA7DRE 443.525 System Fusion Repeater Co-Owner KA7FVV 147.320 KBARA Repeater ka7fvv.net
On Mar 25, 2019, at 08:15, John Brier [email protected] wrote:
This came up on Twitter recently. [1] When I first started using SO-50 I assumed once the transponder was turned on with the 74.4 Hz tone it would stay on as long as it was being used (people are uplinking with a 67 HZ tone), but in fact it turns off every 10 minutes regardless of activity.
If you ever hear it go silent in the middle of a busy pass try sending a 74.4 hz tone to reset the timer/turn the transponder back on.
73, John Brier KG4AKV
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
I was aware of that page and you are correct that I assumed it meant 10 minutes with no use. I propose the text on that web page be replaced with the below text. I have slightly edited the intro, rewrote the middle and added new information, and left the last paragraph alone completely:
SO-50 includes a V/u FM repeater operating with a 145.850 MHz uplink and 436.795 MHz (+/- 10 KHz) downlink. The repeater is available to amateurs worldwide. To use the repeater it must first be turned on by transmitting a carrier with a 74.4 Hz PL tone for two seconds. Once it is turned on you must use a 67 Hz tone to communicate through it. After 10 minutes, even if it is in use, the repeater will turn off. To turn it back on transmit a carrier with a 74.4 Hz PL tone for two seconds again.
Over populated regions of the world, usually a knowledgeable station on the fringe of the region who is in range of the satellite before the majority of the region will turn the repeater on, but not always. Also, usually a knowledgeable station will turn the repeater on again after it turns off in between a pass over the region, but not always.
It is best to be able to turn it on yourself if needed, especially if you are in a less populated region, are on the fringe of a populated region, or operate during times when the satellite is likely to have little activity, like late at night or early in the morning.
The repeater has no hang time so you cannot tell if you are successfully accessing the repeater by listening for a short carrier or courtesy beep after your transmissions like you can with most terrestrial repeaters. Assuming you can hear others on the repeater, the best way to verify you are successfully accessing the repeater is by using a full-duplex setup and listening for your voice on the downlink while you transmit on the uplink.
The repeater consists of a miniature VHF receiver with sensitivity of -124dBm, having an IF bandwidth of 15 KHz. The receive antenna is a 1/4 wave vertical mounted in the top corner of the spacecraft. The receive audio is filtered and conditioned then gated in the control electronics prior to feeding it to the 250mW UHF transmitter. The downlink antenna is a 1/4 wave mounted in the bottom corner of the spacecraft and canted at 45 degrees inward.
On Mon, Mar 25, 2019 at 4:17 PM Burns Fisher [email protected] wrote:
The 10-minute timer is documented here: https://www.amsat.org/two-way-satellites/so-50-satellite-information/ although I can see you might assume that the 10 minutes means "10 minutes with no use".
But I was always told "don't worry about the 10 minute timer--someone will have triggered it". Maybe the "someones" who used to trigger it frequently are using it less than they used to :-)
Burns
On Mon, Mar 25, 2019 at 2:03 PM Scott via AMSAT-BB [email protected] wrote:
John,
I have noticed that over the last couple years. Have had to turn it back on during several passes. I never remember having to do that in the early years of the sat. Maybe it is showing its age.
73, Scott, KA7FVV Director - KBARA. kbara.org Alternate Board of Director - AMSAT amsat.org Co-Owner WA7DRE 443.525 System Fusion Repeater Co-Owner KA7FVV 147.320 KBARA Repeater ka7fvv.net
On Mar 25, 2019, at 08:15, John Brier [email protected] wrote:
This came up on Twitter recently. [1] When I first started using SO-50 I assumed once the transponder was turned on with the 74.4 Hz tone it would stay on as long as it was being used (people are uplinking with a 67 HZ tone), but in fact it turns off every 10 minutes regardless of activity.
If you ever hear it go silent in the middle of a busy pass try sending a 74.4 hz tone to reset the timer/turn the transponder back on.
73, John Brier KG4AKV
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
-
Burns Fisher -
John Brier -
Scott