[amsat-bb] AO-51 power levels

[Gould Smith]

I am still trying to tweak the power levels to get through all the eclipes 
during the day.

Tonight I changed TXA (L/U) to 210 mW and TXB (V/U) to 290 (as low as I can 
get it without turning it off).
The eclipse I measured on one pass tonight was 16:05 minutes +- 5 sec.  The 
eclipse time should start to decrease over the next few days.

73,
Gould, WA4SXM
----- Original Message ----- 
From: <n3tl at bellsouth.net>
To: "Jeff Yanko" <wb3jfs at cox.net>; <amsat-bb at amsat.org>
Sent: Thursday, June 25, 2009 9:45 PM
Subject: [amsat-bb] Re: AO-51


> If I recall correctly from a post last week, the U/V pair is operating at 
> roughly 290 milliwatts RF out on transmit, and the L/U pair is at roughly 
> 260 mW. In other words, each transmitter is operating on slightly more 
> than SO-50 (250 mW) power levels.
>
> I have had passes this week where the satellite was armchair copy on one 
> pass, and about like has been described this evening on another. I suspect 
> the lower power levels (half or less of what has been nominal for most of 
> the past year) and the inevitable mismatch (depending on the angle between 
> the satellite and a given ground station) of its circular-polarized 
> antennas to many ground stations' linear-polarized antennas are 
> contributing to the reception differences.
>
> Drew (KO4MA) or Gould (WA4SXM) can comment - and I hope they will if this 
> is incorrect - but I suspect that AO-51 continues to operate as it has 
> recently. I appreciate very much their efforts to maintain the satellite. 
> That being said, it will definitely prove to be a challenge to work for 
> many Field Day stations.
>
> I hope I can get the one contact on it that I can count for the club FD 
> effort I'll be a part of. And I hope that other stations will make their 
> one allowed contact and give other stations the same chance to get theirs.
>
> Best of Field Day luck and 73 to all,
>
> Tim - N3TL
> -------------- Original message from "Jeff Yanko" 
> <wb3jfs at cox.net>: -------------- 
>
>
>> Wondering if AO-51 is operating? Just listened for the 2357z pass and
>> nothing received. The last time I checked the status of the bird it shows
>> that the 435.300 downlink was active. I also listened for the 435.150 to 
>> no
>> avail.
>>
>>
>> 73,
>>
>> Jeff WB3JFS
>> Las Vegas, NV
>> DM26
>>
>>
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