i found out from a friend that there could be one of two related problems if not adjusted properly. Make sure the sound card you are using is set to 48k not 44.1. In the MMSSTV there is a software adjustment screen, sorry I'm not sitting in front of the computer, that allows you to set a parameter to 24000, exactly half of the sound card setting. The MMSSTV default setting is not 24000 and needs to be set to that. You then should get good clean images.
I set up both RS-SSTV and MMSSTV and got good images yesterday from both.
73 and happy holidays! Rick W2JAZ
Rick,
Excellent point, and one I did as a matter of routine since it is important with SDR rigs. Just looked and it can be found here:
Options Setup Misc Then the Clock section at the bottom of the page.
The sound card adjustments will vary slightly depending on the version of the OS you are running, but usually will be under the advanced properties for the device. You can _probably_ use a higher sampling rate for the sound card so long as it is a power of 2 multiple (2,4,8, etc) of the value in MMSSTV. For instance, I use 192k (8x) with no issues. The same applies to most similar software.
73s,
Alan WA4SCA
<-----Original Message----- <From: amsat-bb-bounces@amsat.org [mailto:amsat-bb-bounces@amsat.org] On Behalf Of Richard Lawn <Sent: Friday, December 19, 2014 7:25 AM <To: amsat-bb@amsat.org <Subject: [amsat-bb] MMSSTV and images from ISS < <i found out from a friend that there could be one of two related problems <if not adjusted properly. Make sure the sound card you are using is set to <48k not 44.1. In the MMSSTV there is a software adjustment screen, sorry <I'm not sitting in front of the computer, that allows you to set a <parameter to 24000, exactly half of the sound card setting. The MMSSTV <default setting is not 24000 and needs to be set to that. You then should <get good clean images. < <I set up both RS-SSTV and MMSSTV and got good images yesterday from both. < <73 and happy holidays! <Rick W2JAZ <_______________________________________________ <Sent via AMSAT-BB@amsat.org. 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!Rick <Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Thanks for clarifying this better than I did Alan! I was sitting at the breakfast table when I wrote the initial posting and couldn't remember where that setup page was in MMSTV. And yes, the math is simple as long as it's divisible by 2. This came up when Dave W0DHB and Ron W5RKN and I were getting prepared for the two days of ISS SSTV passes. Happy to pass the do on. And you are right again regarding the importance of these parameter settings when using my FunCube Dongle or softrock.
Now we can all look forward to tomorrow and some new images. I was only able to get one clean, complete image per pass yesterday so there is little hope to grab all 12!
happy holidays! Rick W2JAZ
On Friday, December 19, 2014, Alan <wa4sca@gmail.com javascript:_e(%7B%7D,'cvml','wa4sca@gmail.com');> wrote:
Rick,
Excellent point, and one I did as a matter of routine since it is important with SDR rigs. Just looked and it can be found here:
Options Setup Misc Then the Clock section at the bottom of the page.
The sound card adjustments will vary slightly depending on the version of the OS you are running, but usually will be under the advanced properties for the device. You can _probably_ use a higher sampling rate for the sound card so long as it is a power of 2 multiple (2,4,8, etc) of the value in MMSSTV. For instance, I use 192k (8x) with no issues. The same applies to most similar software.
73s,
Alan WA4SCA
<-----Original Message----- <From: amsat-bb-bounces@amsat.org [mailto:amsat-bb-bounces@amsat.org] On Behalf Of Richard Lawn <Sent: Friday, December 19, 2014 7:25 AM <To: amsat-bb@amsat.org <Subject: [amsat-bb] MMSSTV and images from ISS < <i found out from a friend that there could be one of two related problems <if not adjusted properly. Make sure the sound card you are using is set to <48k not 44.1. In the MMSSTV there is a software adjustment screen, sorry <I'm not sitting in front of the computer, that allows you to set a <parameter to 24000, exactly half of the sound card setting. The MMSSTV <default setting is not 24000 and needs to be set to that. You then should <get good clean images. < <I set up both RS-SSTV and MMSSTV and got good images yesterday from both. < <73 and happy holidays! <Rick W2JAZ <_______________________________________________ <Sent via AMSAT-BB@amsat.org. 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!Rick <Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
I wasn't listening yesterday, but generally the duty cycle is 180 seconds on and 180 seconds off, so the most you'd ever get in one 9.5 minute pass in two complete images, and only then if you're in the right place and the first transmission begins right at your AOS.
73,
Paul, N8HM
On Fri, Dec 19, 2014 at 8:58 AM, Richard Lawn rjlawn@gmail.com wrote:
Thanks for clarifying this better than I did Alan! I was sitting at the breakfast table when I wrote the initial posting and couldn't remember where that setup page was in MMSTV. And yes, the math is simple as long as it's divisible by 2. This came up when Dave W0DHB and Ron W5RKN and I were getting prepared for the two days of ISS SSTV passes. Happy to pass the do on. And you are right again regarding the importance of these parameter settings when using my FunCube Dongle or softrock.
Now we can all look forward to tomorrow and some new images. I was only able to get one clean, complete image per pass yesterday so there is little hope to grab all 12!
happy holidays! Rick W2JAZ
On Friday, December 19, 2014, Alan <wa4sca@gmail.com javascript:_e(%7B%7D,'cvml','wa4sca@gmail.com');> wrote:
Rick,
Excellent point, and one I did as a matter of routine since it is important with SDR rigs. Just looked and it can be found here:
Options Setup Misc Then the Clock section at the bottom of the page.
The sound card adjustments will vary slightly depending on the version of the OS you are running, but usually will be under the advanced properties for the device. You can _probably_ use a higher sampling rate for the sound card so long as it is a power of 2 multiple (2,4,8, etc) of the value in MMSSTV. For instance, I use 192k (8x) with no issues. The same applies to most similar software.
73s,
Alan WA4SCA
<-----Original Message----- <From: amsat-bb-bounces@amsat.org [mailto:amsat-bb-bounces@amsat.org] On Behalf Of Richard Lawn <Sent: Friday, December 19, 2014 7:25 AM <To: amsat-bb@amsat.org <Subject: [amsat-bb] MMSSTV and images from ISS < <i found out from a friend that there could be one of two related problems <if not adjusted properly. Make sure the sound card you are using is set to <48k not 44.1. In the MMSSTV there is a software adjustment screen, sorry <I'm not sitting in front of the computer, that allows you to set a <parameter to 24000, exactly half of the sound card setting. The MMSSTV <default setting is not 24000 and needs to be set to that. You then should <get good clean images. < <I set up both RS-SSTV and MMSSTV and got good images yesterday from both. < <73 and happy holidays! <Rick W2JAZ <_______________________________________________ <Sent via AMSAT-BB@amsat.org. 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!Rick <Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via AMSAT-BB@amsat.org. 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://amsat.org/mailman/listinfo/amsat-bb
participants (3)
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Alan -
Paul Stoetzer -
Richard Lawn