Using 10 Watts, I have not been able to get into AO-92 L Band.
From the AO-92 web site:
================
......Since the 435 MHz uplink antenna is used to receive the 1267 MHz signals and may present a mismatch at that frequency, pre-launch estimates suggest that a power level of 100 watts ERP will be required for horizon-to-horizon access in Mode L/v. AMSAT Engineering will issue further guidance after in-orbit testing. Look for future articles on the AMSAT website and in The AMSAT Journal for equipment ideas and tutorials for accessing the L-band uplink. ====================
Perhaps my 10 Watts are too low. Have there been updates from AMSAT on recommended L band power? What power do others run?
Alan WA9WUD
On 07/08/20 16:51, Alan Blind via AMSAT-BB wrote:
Perhaps my 10 Watts are too low. Have there been updates from AMSAT on recommended L band power? What power do others run?
Alan,
Out of curiosity, what is your antenna and calculated EIRP?
I have a nearly-complete 1.2GHz FM rig that just needs to go into a box. (http://www.pe1jpd.nl/index.php/23cm_nbfm/ with the AO-92 mod.)
--- Zach N0ZGO
Hi Alan!
I have been using 10W from an old Kenwood TM-541A 1.2 GHz FM mobile, connected to a 10-element Yagi with 6 feet of coax. I was on two passes earlier this morning, and two passes last night. Even with the smallest tuning steps on the TM-541A at 10 watts, I am able to get through during most of almost any pass. I have been using this setup for the past few months.
In the past, I was working AO-92 L/V with 1 watt from an Alinco DJ-G7T HT into the same coax and Yagi. The DJ-G7T tunes in 5 kHz steps, which is helpful at the lower power level. The AFC in AO-92's uplink receiver doesn't appear to work with weaker signals, where the 10W from the TM-541A works even if I am a couple of kHz from what the Doppler-adjusted uplink frequency would be at some moments during passes.
What radio, coax, and antenna are you using for your 1.2 GHz uplink?
73!
Patrick WD9EWK/VA7EWK http://www.wd9ewk.net/ Twitter: @WD9EWK or http://twitter.com/WD9EWK
On Wed, Jul 8, 2020 at 9:52 PM Alan Blind via AMSAT-BB [email protected] wrote:
Using 10 Watts, I have not been able to get into AO-92 L Band.
<snip>
Perhaps my 10 Watts are too low. Have there been updates from AMSAT on recommended L band power? What power do others run?
Alan WA9WUD
Patrick:
rig - Down East Microwave L24X Transmit converter coax - 150 feet LMR-600 antenna - M2 23CM22EZA , 18 dbi gain, Horizontal, Diamond SX1100 Power meter, SWR is 1.4:1 TX PL tone 67.0 kHZ
I have pushed the TX to 20 watts, but also, did not hear myself.
AO-92 U/v works just fine, so I know my RX is OK.
Alan WA9WUD
On Wed, Jul 8, 2020 at 6:10 PM Patrick STODDARD (WD9EWK/VA7EWK) < [email protected]> wrote:
Hi Alan!
I have been using 10W from an old Kenwood TM-541A 1.2 GHz FM mobile, connected to a 10-element Yagi with 6 feet of coax. I was on two passes earlier this morning, and two passes last night. Even with the smallest tuning steps on the TM-541A at 10 watts, I am able to get through during most of almost any pass. I have been using this setup for the past few months.
In the past, I was working AO-92 L/V with 1 watt from an Alinco DJ-G7T HT into the same coax and Yagi. The DJ-G7T tunes in 5 kHz steps, which is helpful at the lower power level. The AFC in AO-92's uplink receiver doesn't appear to work with weaker signals, where the 10W from the TM-541A works even if I am a couple of kHz from what the Doppler-adjusted uplink frequency would be at some moments during passes.
What radio, coax, and antenna are you using for your 1.2 GHz uplink?
73!
Patrick WD9EWK/VA7EWK http://www.wd9ewk.net/ Twitter: @WD9EWK or http://twitter.com/WD9EWK
On Wed, Jul 8, 2020 at 9:52 PM Alan Blind via AMSAT-BB [email protected] wrote:
Using 10 Watts, I have not been able to get into AO-92 L Band.
<snip>
Perhaps my 10 Watts are too low. Have there been updates from AMSAT on recommended L band power? What power do others run?
Alan WA9WUD
Hi Alan, I use 10 watts from my Icom IC-9700. I run about 100 feet of LMR 600 coax so maybe 5 watts to the antenna. I use a 35 element yagi antenna. I made the satellite today at 14 degrees elevation OK. 73sLynnKD9BVG
On Wednesday, July 8, 2020, 04:53:09 PM CDT, Alan Blind via AMSAT-BB [email protected] wrote:
Using 10 Watts, I have not been able to get into AO-92 L Band.
From the AO-92 web site:
================
......Since the 435 MHz uplink antenna is used to receive the 1267 MHz signals and may present a mismatch at that frequency, pre-launch estimates suggest that a power level of 100 watts ERP will be required for horizon-to-horizon access in Mode L/v. AMSAT Engineering will issue further guidance after in-orbit testing. Look for future articles on the AMSAT website and in The AMSAT Journal for equipment ideas and tutorials for accessing the L-band uplink. ====================
Perhaps my 10 Watts are too low. Have there been updates from AMSAT on recommended L band power? What power do others run?
Alan WA9WUD _______________________________________________ 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
All
The important thing to remember is ERP. Using the KV5R calculator and assuming an SWR or 1.2:! the ERP for this contact was 618 watts. ( http://kv5r.com/ham-radio/coax-loss-calculator/) The antenna gain was based on the published gain for the M2 35 element Yagi .
Ten watts may or may not be enough. What we need to do is look at the overall system of losses ( coax) and gains (antenna).
Hope this helps
John K4SQC
On Thu, Jul 9, 2020 at 10:13 AM Lynn Palmer via AMSAT-BB [email protected] wrote:
Hi Alan, I use 10 watts from my Icom IC-9700. I run about 100 feet of LMR 600 coax so maybe 5 watts to the antenna. I use a 35 element yagi antenna. I made the satellite today at 14 degrees elevation OK. 73sLynnKD9BVG
On Wednesday, July 8, 2020, 04:53:09 PM CDT, Alan Blind via AMSAT-BB <[email protected]> wrote:
Using 10 Watts, I have not been able to get into AO-92 L Band.
From the AO-92 web site:
================
......Since the 435 MHz uplink antenna is used to receive the 1267 MHz signals and may present a mismatch at that frequency, pre-launch estimates suggest that a power level of 100 watts ERP will be required for horizon-to-horizon access in Mode L/v. AMSAT Engineering will issue further guidance after in-orbit testing. Look for future articles on the AMSAT website and in The AMSAT Journal for equipment ideas and tutorials for accessing the L-band uplink. ====================
Perhaps my 10 Watts are too low. Have there been updates from AMSAT on recommended L band power? What power do others run?
Alan WA9WUD _______________________________________________ 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
John, Yes, of course you are right. It is important to understand ERP to make comparisons. If I use my actual measured SWR and account for additional losses due to a jumper thru the entrance panel and into the shack, the calculated ERP is probably closer to 500 watts assuming the M2 published gain data of 20.94 dBi represents the actual performance of my "as installed" antenna setup. 73sLynn KD9BVG On Thursday, July 9, 2020, 11:15:38 AM CDT, John Kludt [email protected] wrote:
All The important thing to remember is ERP. Using the KV5R calculator and assuming an SWR or 1.2:! the ERP for this contact was 618 watts. ( http://kv5r.com/ham-radio/coax-loss-calculator/)%C2%A0 The antenna gain was based on the published gain for the M2 35 element Yagi . Ten watts may or may not be enough. What we need to do is look at the overall system of losses ( coax) and gains (antenna). Hope this helps John K4SQC On Thu, Jul 9, 2020 at 10:13 AM Lynn Palmer via AMSAT-BB [email protected] wrote:
Hi Alan, I use 10 watts from my Icom IC-9700. I run about 100 feet of LMR 600 coax so maybe 5 watts to the antenna. I use a 35 element yagi antenna. I made the satellite today at 14 degrees elevation OK. 73sLynnKD9BVG
On Wednesday, July 8, 2020, 04:53:09 PM CDT, Alan Blind via AMSAT-BB [email protected] wrote:
Using 10 Watts, I have not been able to get into AO-92 L Band.
From the AO-92 web site:
================
......Since the 435 MHz uplink antenna is used to receive the 1267 MHz signals and may present a mismatch at that frequency, pre-launch estimates suggest that a power level of 100 watts ERP will be required for horizon-to-horizon access in Mode L/v. AMSAT Engineering will issue further guidance after in-orbit testing. Look for future articles on the AMSAT website and in The AMSAT Journal for equipment ideas and tutorials for accessing the L-band uplink. ====================
Perhaps my 10 Watts are too low. Have there been updates from AMSAT on recommended L band power? What power do others run?
Alan WA9WUD _______________________________________________ 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
Alan,
I'm using 10w (ICOM IC-9700) through 50 feet LMR-400 into a Directive Systems 24 Element Loop Yagi. No issues getting in when the L-Band is enabled ( currently on Wednesday's )
Cal/N3CAL
-----Original Message----- From: AMSAT-BB [mailto:[email protected]] On Behalf Of Alan Blind via AMSAT-BB Sent: Wednesday, July 08, 2020 5:51 PM To: [email protected] Subject: [amsat-bb] AO-92 L Band Power
Using 10 Watts, I have not been able to get into AO-92 L Band.
From the AO-92 web site:
================
......Since the 435 MHz uplink antenna is used to receive the 1267 MHz signals and may present a mismatch at that frequency, pre-launch estimates suggest that a power level of 100 watts ERP will be required for horizon-to-horizon access in Mode L/v. AMSAT Engineering will issue further guidance after in-orbit testing. Look for future articles on the AMSAT website and in The AMSAT Journal for equipment ideas and tutorials for accessing the L-band uplink. ====================
Perhaps my 10 Watts are too low. Have there been updates from AMSAT on recommended L band power? What power do others run?
Alan WA9WUD _______________________________________________ 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
Alan- IC-910 10W through 70 feet of LMR600 24 el looper. Works great. 73 Bob W7LRD
On 07/08/2020 2:51 PM Alan Blind via AMSAT-BB [email protected] wrote:
Using 10 Watts, I have not been able to get into AO-92 L Band.
From the AO-92 web site:
================
......Since the 435 MHz uplink antenna is used to receive the 1267 MHz signals and may present a mismatch at that frequency, pre-launch estimates suggest that a power level of 100 watts ERP will be required for horizon-to-horizon access in Mode L/v. AMSAT Engineering will issue further guidance after in-orbit testing. Look for future articles on the AMSAT website and in The AMSAT Journal for equipment ideas and tutorials for accessing the L-band uplink. ====================
Perhaps my 10 Watts are too low. Have there been updates from AMSAT on recommended L band power? What power do others run?
Alan WA9WUD _______________________________________________ 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
On 7/8/2020 16:51, Alan Blind via AMSAT-BB wrote:
Using 10 Watts, I have not been able to get into AO-92 L Band.
Hi Alan,
Perhaps it's something else, just for thought. At 1267 MHz frequency is important and with the higher Doppler shift and perhaps other slightly stronger or closer to center frequency uplink signals might be captured. AFC favors stronger, at least fairly constant strength signals and those closer to the center frequency. You may have enough power but are just enough off frequency to be bested by other signals, off frequency can be because of PC clock, lat/long (your QTH) in the tracking program, the accuracy of your transmitter, and items of a similar nature.
I have spent a few passes over the years being off frequency or even stupidly off frequency or even off (wrong) band, wrong Doppler.sqf line selected in the CAT window, no/wrong CTCSS, or forgot to engage antenna tracking, that kinda stuff that just happens. Sometimes the cats turn off the radio when I'm not looking, just before a pass. Nobody knows about these problems though because I haven't told anyone, if somebody asks where I was I just say like "no, I didn't get on for that pass".
Jerry Buxton, NØJY
Hi Alan, in the rather safe than sorry category—check your uplink frequency. After launch we quickly determined a “best” uplink was 1267.359 MHzMost folks find this to be pretty good. Then Doppler correction is important at these frequencies, so adjust for that as well. One night I wasn’t quite getting into the bird and knew I should have been. It was just a couple kHz off, but enough to make a big difference. Give that a shot anyhow. Easy for radios to be off a tad at these high frequencies, too.
Hope to work you on L-band soon!
Mark N8MH
On Wed, Jul 8, 2020 at 5:52 PM Alan Blind via AMSAT-BB [email protected] wrote:
Using 10 Watts, I have not been able to get into AO-92 L Band.
From the AO-92 web site:
================
......Since the 435 MHz uplink antenna is used to receive the 1267 MHz signals and may present a mismatch at that frequency, pre-launch estimates suggest that a power level of 100 watts ERP will be required for horizon-to-horizon access in Mode L/v. AMSAT Engineering will issue further guidance after in-orbit testing. Look for future articles on the AMSAT website and in The AMSAT Journal for equipment ideas and tutorials for accessing the L-band uplink. ====================
Perhaps my 10 Watts are too low. Have there been updates from AMSAT on recommended L band power? What power do others run?
Alan WA9WUD _______________________________________________ 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
participants (9)
-
73 Bob W7LRD -
Alan Blind -
Cal Spreitzer -
Jerry Buxton -
John Kludt -
Lynn Palmer -
Mark L. Hammond -
Patrick STODDARD (WD9EWK/VA7EWK) -
Zach Metzinger