Re: accidental satellite ops
Glen,
Actually, AO-7 was placed in the narrow-band (CW/SSB) subband back when it was launched. AS I recall a waiver was sought to do this. So AO-7 is, in fact, in the wrong frequency allocation for satellite operations. Perhaps Tom Clark or one of the other old hands that were involved when AO-7 was built/launched can better state this (I was a member of sbms that built the 2.3 GHz transponder that was never allowed activation).
As far as attracting new satellite operators, there is an even chance since the operator already is in possession of CW/SSB equipment that is required for AO-7. Basically, they would need proper antennas and learning about tracking issues (times, freq. Doppler, etc.). Also that the input is inverted so one tranmits LSB to hear USB. Most of the weak-signal group (CW/SSB) are pretty savy bunch, so it remains whether it would interest them.
73, Ed - KL7UW
Original Message: ----------------- From: Glen Zook gzook@yahoo.com Date: Thu, 17 Sep 2009 08:25:11 -0700 (PDT) To: amsat-bb@amsat.org, sparkycivic@shaw.ca Subject: [amsat-bb] Re: accidental satellite ops
The primary problem is that the OSCAR VII inputs are now in the weak signal portions of the "band plans". With the proliferation of FM activity the weak signal portions have been compressed. It is unrealistic to even think of "blaming" the weak signal operators for interfering with OSCAR VII operations. Remember, OSCAR VII is 35 years old and was not expected to be in service for more than just a few years.
One should just be happy that OSCAR VII is still usable and work around the occasional situation with unintentional interference. Besides, there are not that many contests on the VHF and UHF bands and most of the time there is little activity in the weak signal portions of 2-meters and 70 cm.
As for garnering additional satellite operators that is definitely a possibility. However, I don't know how many new operators would actually be recruited.
Glen, K9STH AMSAT 239 / LM 463
Website: http://k9sth.com
--- On Wed, 9/16/09, Auke de Jong sparkycivic@shaw.ca wrote:
maybe the best one can do is to send QSL cards noting the time/freq/sat/mode to the ops. Of course this assumes that their callsign can be understood
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I went back in my copies of the AMSAT Newsletter (I have virtually all of them starting with Volume I, Number 2, dated October 1969 - I joined AMSAT the 2nd month of the organization's existence) and the only mention of a waiver was that due to the control requirements that a waiver was requested for OSCAR I through OSCAR VII. Volume V, Number 1, March 1973, page 19, describes the frequency selection for the OSCAR VII transponders and the mention is made that the life expectancy was 3 years. But, there was no mention of a waiver due to the frequency selection.
Volume V, Number 4, December 1973, has a lengthy article on the capabilities of OSCAR VII. Again, no mention of a waiver because of the frequency selection. On page 18 of that issue there is an announcement of Notice of Inquiry from the FCC concerning rules for the newly proposed Amateur Radio Satellite Service.
Volume VI, Number 2, June 1974, has AMSAT's official response to the Notice of Inquiry by the FCC starting on page 8.
Remember, before the establishment of the Amateur Radio Satellite Service there was nothing in the FCC regulations concerning the frequencies even suggested, let alone required.
These days 47 CFR Part 97 Section 97.207(c)(2) specifies, among other frequencies, 144 MHz to 146 MHz and 435 MHz to 438 MHz as the allowed frequency segments for satellite operation. But, prior to either late 1974 or early 1975 there were no specified frequencies for satellite operation. Of course the frequency range of 144 MHz to 146 MHz definitely encompasses the "weak signal" portion of the 2-meter band. The 435 MHz to 438 MHz segment is well above the present "weak signal" portion of the 70 cm band.
It is my opinion that the segment around 432.150 MHz was chosen because the vast majority of operators that had 70 cm capabilities were operating very near this segment and therefore no additional transmitting equipment would have to be acquired. Also, most 432 MHz operators also had 2-meter capabilities and could easily "hear" the downlink.
Glen, K9STH AMSAT 239 / LM 463
Website: http://k9sth.com
--- On Thu, 9/17/09, kl7uw@acsalaska.net kl7uw@acsalaska.net wrote:
Actually, AO-7 was placed in the narrow-band (CW/SSB) subband back when it was launched. AS I recall a waiver was sought to do this. So AO-7 is, in fact, in the wrong frequency allocation for satellite operations. Perhaps Tom Clark or one of the other old hands that were involved when AO-7 was built/launched can better state this (I was a member of sbms that built the 2.3 GHz transponder that was never allowed activation).
As far as attracting new satellite operators, there is an even chance since the operator already is in possession of CW/SSB equipment that is required for AO-7. Basically, they would need proper antennas and learning about tracking issues (times, freq. Doppler, etc.). Also that the input is inverted so one tranmits LSB to hear USB. Most of the weak-signal group (CW/SSB) are pretty savy bunch, so it remains whether it would interest them.
The July/August 2002 AMSAT Journal has a copy of the waiver on page 25, dated April 19, 1974.
At the time of the construction of the satellite, there was no separate amateur satellite service. By the time of the launch, there was, and it was 435-438 only, hence the waiver.
73, Drew KO4MA
That clears that up!
Glen, K9STH
Website: http://k9sth.com
--- On Thu, 9/17/09, Andrew Glasbrenner glasbrenner@mindspring.com wrote:
The July/August 2002 AMSAT Journal has a copy of the waiver on page 25, dated April 19, 1974.
At the time of the construction of the satellite, there was no separate amateur satellite service. By the time of the launch, there was, and it was 435-438 only, hence the waiver.
----- Original Message ----- From: kl7uw@acsalaska.net To: gzook@yahoo.com; amsat-bb@amsat.org; sparkycivic@shaw.ca Sent: Thursday, September 17, 2009 9:52 PM Subject: [amsat-bb] Re: accidental satellite ops
Glen,
<snip>
(I was a member of sbms that built the 2.3 GHz transponder that was never allowed activation).
73, Ed - KL7UW
Hi Ed, KL7UW
As far I know the 2304.1 MHz transmitter on board of OSCAR-7 was only a beacon and not a transponder.
73" de
i8CVS Domenico
Hi Dom,
Correct. There are a couple of selectable modulation modes like M.C. TLM etc. But it can never be activated. I have copies of the FCC paperwork where they denied the request.
73, Mike, N1JEZ AO-7 Cmd Op AMSAT 29649 "A closed mouth gathers no feet"
----- Original Message ----- From: "i8cvs" domenico.i8cvs@tin.it To: kl7uw@acsalaska.net; gzook@yahoo.com; "AMSAT-BB" amsat-bb@amsat.org; "Auke de Jong, VE6PWN" sparkycivic@shaw.ca Sent: Friday, September 18, 2009 7:59 AM Subject: [amsat-bb] Re: accidental satellite ops
----- Original Message ----- From: kl7uw@acsalaska.net To: gzook@yahoo.com; amsat-bb@amsat.org; sparkycivic@shaw.ca Sent: Thursday, September 17, 2009 9:52 PM Subject: [amsat-bb] Re: accidental satellite ops
Glen,
<snip>
(I was a member of sbms that built the 2.3 GHz transponder that was never allowed activation).
73, Ed - KL7UW
Hi Ed, KL7UW
As far I know the 2304.1 MHz transmitter on board of OSCAR-7 was only a beacon and not a transponder.
73" de
i8CVS Domenico
Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
participants (5)
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Andrew Glasbrenner
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Glen Zook
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i8cvs
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kl7uw@acsalaska.net
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n1jez@burlingtontelecom.net