
Hello,
Please what is the minimum power that i should use to send data for cubesat. 20w is it sufficient? When i increase the power in the icom 9100, the icom restart once i exceed approximately 35w. What is the problem.
Thank you. Best regards Kais

Hello Kais, I have been able to send data (APRS or DTMF) with 5 watts - under perfect conditions. Because conditions are not normally perfect - I typically transmit at 35 watts - but 20 watts should be plenty of power. 73 Robert MacHale. KE6BLR FCC Licensed Radio Operator . http://www.aprsat.com/predict . http://www.spaceCommunicator.club%C2%A0 . Supporting Boy Scout Merit Badges in Radio, Robotics, and Space Exploration
Silly Joke: What did the little mountain say to the bigger mountain? Hi Cliff!
He who dares not offend cannot be honest. -- THOMAS PAINE There is nothing noble in being superior to your fellow men. True nobility lies in being superior to your former self. -- ERNEST HEMINGWAY
On Sunday, May 23, 2021, 10:54:13 AM PDT, belwafi kais [email protected] wrote:
Hello, Please what is the minimum power that i should use to send data for cubesat. 20w is it sufficient?When i increase the power in the icom 9100, the icom restart once i exceed approximately 35w. What is the problem. Thank you.Best regardsKais
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If the Icom restarts when you increase the power the power supply might not be providing enough current, or there could be a connection problem with the power cables.
Radios can also restart due to high SWR. It is a protection circuit. If that was the issue though I would think it would happen at lower power levels too, though.
73, John Brier KG4AKV
On Sun, May 23, 2021, 13:54 belwafi kais [email protected] wrote:
Hello,
Please what is the minimum power that i should use to send data for cubesat. 20w is it sufficient? When i increase the power in the icom 9100, the icom restart once i exceed approximately 35w. What is the problem.
Thank you. Best regards Kais
Sent via AMSAT-BB(a)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. Acceptable Use and Privacy Policies available at https://www.amsat.org/about-amsat/
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Full modulation for data or tone (anywhere, not just satellites) is less than you are used to for voice. Sometimes it might be good to experiment with backing off the modulation, power might not be the problem.
On Sun, May 23, 2021, 18:17 John Brier [email protected] wrote:
If the Icom restarts when you increase the power the power supply might not be providing enough current, or there could be a connection problem with the power cables.
Radios can also restart due to high SWR. It is a protection circuit. If that was the issue though I would think it would happen at lower power levels too, though.
73, John Brier KG4AKV
On Sun, May 23, 2021, 13:54 belwafi kais [email protected] wrote:
Hello,
Please what is the minimum power that i should use to send data for cubesat. 20w is it sufficient? When i increase the power in the icom 9100, the icom restart once i exceed approximately 35w. What is the problem.
Thank you. Best regards Kais
Sent via AMSAT-BB(a)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. Acceptable Use and Privacy Policies available at https://www.amsat.org/about-amsat/
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Sent via AMSAT-BB(a)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. Acceptable Use and Privacy Policies available at https://www.amsat.org/about-amsat/
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Sorry for the mis-directed email.
From: [email protected] [email protected] Sent: Monday, May 24, 2021 12:29 To: 'John Brier' [email protected] Subject: RE: [AMSAT-BB] Re: Power to send data to a cubesat
Kais,
This is a follow up to your note – does not address the power required question, but does address the symptom you describe for your IC-9100.
This is a common issue with most newer ICOM radios which have “automotive” AT (large blade style) fuses in the stock power cable. Apparently the fuse and fuse holder contacts become oxidized and develop quite a significant amount of resistance.
Before doing anything more aggressive, try removing the fuses from the holder so you can clean the fuse blades and the holder contacts, then reseat the fuses. If the problem goes away, you have the solution. To prevent it in the future, use some “contact” dressing on the blades. I have found that applying a very small amount of “Jet Lube SS-30” or “Sanchem NO-OX-ID A-Special” seems to prevent the problem from recurring.
Jack Spitznagel – KD4IZ
Assistant Editor – AMSAT News Service
[email protected] mailto:[email protected]
From: John Brier <[email protected] mailto:[email protected] > Sent: Sunday, May 23, 2021 21:17 To: belwafi kais <[email protected] mailto:[email protected] > Cc: AMSAT BB <[email protected] mailto:[email protected] > Subject: [AMSAT-BB] Re: Power to send data to a cubesat
If the Icom restarts when you increase the power the power supply might not be providing enough current, or there could be a connection problem with the power cables.
Radios can also restart due to high SWR. It is a protection circuit. If that was the issue though I would think it would happen at lower power levels too, though.
73, John Brier KG4AKV
On Sun, May 23, 2021, 13:54 belwafi kais <[email protected] mailto:[email protected] > wrote:
Hello,
Please what is the minimum power that i should use to send data for cubesat. 20w is it sufficient?
When i increase the power in the icom 9100, the icom restart once i exceed approximately 35w. What is the problem.
Thank you.
Best regards
Kais
-----------------------------------------------------------
Sent via AMSAT-BB(a)amsat.org http://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. Acceptable Use and Privacy Policies available at https://www.amsat.org/about-amsat/
View archives of this mailing list at https://mailman.amsat.org/hyperkitty/list/[email protected] To unsubscribe send an email to amsat-bb-leave(a)amsat.org http://amsat.org Manage all of your AMSAT-NA mailing list preferences at https://mailman.amsat.org
participants (5)
-
belwafi kais
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Bruce Perens
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John Brier
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kd4iz@frawg.org
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Robert MacHale