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Re: FM vs. Linear on LEOs



First, let me say that I wholeheartedly agree with Drew, FM should be kept 
to the FM birds.

> If the available FM satellites are not enough for your pleasures, step up 
> to the SSB transponders,
>or support a satellite program that intends to build more FM birds, or 
>convince the many educational
> or experimental groups to configure their sats for 2 way FM use when they 
> are done with them (ie
> Saudisat series, Unisat series, Mozhayets series, future cubesats, 
> etc....)


I sure miss being able to operate the linear birds. At my previous QTH, I 
had my 2m / 70 cm crossed yagis
equipped with AZ/EL, and enjoyed operating many birds from the comfort of my 
shack. I even managed
to make some pretty respectable terrestrial contacts on CW/SSB. What fun!

Shortly after I moved to my current QTH, and before I had a chance to 
install antennas, RS 12/13
perished. [sob]    This had been my favorite bird, and I had the privilege 
to meet many of you on this bird. I
also met many OMs on 15m who had no idea that they were inadvertently 
uplinking into a satellite! What
fun it was to tell them I was listening to them on 2m SSB!

 I then turned my attention to AO-40, my first HEO experience. I always 
intended to reinstall the satellite
antennas, but after working AO-40 for a while, I decided that I didn't NEED 
rotors at all! Considering
the harsh Kansas winters and strong winds, roof-mounting my precious gear 
didn't seem like such a good
idea anymore. Also, I'd have added another 50 feet of feed line, further 
attenuating my 20w output on the UHF
uplink.

I did just fine setting up my antennas on the porch each time I had a 
workable pass. Took about 5 minutes
to set up, and 5 minutes to take down.  Between work and family obligations, 
etc my shack time is limited, so I might have only one hour to work AO-40 at 
a time. That meant going outside to 'tweak' the antennas 2 or 3 times. No 
big deal!

So, here we are without AO-40, and my satellite antennas still live in the 
basement!  Lately, I've purchased
an Arrow antenna and operate AO-51 and SO-50 when time allows. For those who 
haven't tried this, you're
missing out on quite a bit of fun! With $80 in radios and a $75 antenna, I'm 
able to work the FM birds. No
expensive feed line to buy, no rotors to worry about.

I would love to work FO-29 and VO-52 if it didn't mean dragging a lot of 
gear outside for a 12 minute pass. My
only other option is to install the whole antenna array on the roof, which I 
may end up doing someday.

It's just too bad that CW/SSB transmitters are not available in a compact 
HT-size package. A few current-model
HTs offer SSB receive, that much I know.

I'm really looking forward to P3E and Eagle, and hoping to work mode U/s 
again!

73 and Happy Holidays,

Kyle Yoksh
K0KN
Olathe, Kansas
Amsat# 35249

----- Original Message ----- 
> Date: Thu, 24 Nov 2005 10:27:02 -0500 (GMT-05:00)
> From: Andrew Glasbrenner
> Subject: Re: [amsat-bb] Hamsat FM
>
> I respectfully disagree. For about $20 users can purchase a single 
> frequency tone encoder for your radio, or build one for much less. 
> Furthermore, once we let the genie out of the bottle of allowing FM on 
> transponders, we'll never get it back in. Pretty soon the small percentage 
> of the hams that don't understand the schedule or agreement will think FM 
> is fine anywhere and anytime, and then the transponders will be useless. 
> Once you go down that road there is no way back.
>
> There are other issues as well. With FM on a transponder there is nothing 
> holding users to one pair of frequencies. Without tuning for Doppler, or 
> with crude 5 kHz steps and no AFC on the satellite to center things, the 
> users would be all over the passband. Once you add multiple users, like 
> would happen over Europe and the US, the downlink power would be split 
> over a wide bandwidth as the various user uplinks diverge because of 
> Doppler. Pretty soon instead of one fat hog that can hear himself on FM, 
> you have lots of little squealing piggies sharing the one watt of downlink 
> power over 30 kHz that can't hear anything coherent and have ruined the 
> satellite for everyone. Over India, and probably the extreme north like 
> where you are, the single FM users survives on VO-52 simply because there 
> is no competition.
>
> Allowing or encouraging FM on transponders is a dumbing down of AMSAT that 
> I will not stand by to see happen. If the available FM satellites are not 
> enough for your pleasures, step up to the SSB transponders, or support a 
> satellite program that intends to build more FM birds, or convince the 
> many educational or experimental groups to configure their sats for 2 way 
> FM use when they are done with them (ie Saudisat series, Unisat series, 
> Mozhayets series, future cubesats, etc....)
>
> When Posat comes online again, I'll bet there will be no tone. Posat is 
> bigger than your average FM sat like 27, 50, or 51 and has more power 
> available. With it's big hairy downlink it will be like the heyday of it's 
> predecessor UO-14, and we'll all forget about using FM on transponders.
>
> Happy Thanksgiving for those celebrating today and 73 to all,
>
> Drew KO4MA
----
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