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Re: Questions about operating F0-20 & 29



Hi "rover"
I use M2 HO-loops while mobile and work FO-20 and FO-29 just about
daily.
UP:  2m HO-loop, IC-290H.  Usually have the brick on too, about 100W to
the antenna.  On high elevation passes I can frequently turn off the amp
and work fine with only about 15W to the antenna.  CW/SSB either way, no
problem.
DOWN: 70cm HO-loop, FT-100, ARR preamp.  With the low-gain antenna the
preamp is a MUST.

There is a fair amount of fading on the birds--they are not stabilized
at all--but I can work most of every pass.  When they are good, they're
very good.  Note that FO-20 has poor/no battery performance and
generally performs very poorly when eclipsed.

Many use M2 eggbeaters or the equivalent.  I used an M2 eggbeater on
70cm for some time, but do not notice any real difference between it and
the horizontally-polarized HO-loop.

Doppler correction is constant, really...seems to be about 8-9kHz per
pass (which average around 18 minutes), so nearly 500Hz/minute.  Please
adjust your RX freq only or stations will tire of chasing you around (I
know I will...I have to do this while driving!)

I regret to say that I have heard very little DX...USA and VE only.  

As a bonus you could work UO-14 (FM) as well, as noted by others.  


Wayne Day N5WD wrote:
> 
> On Thu, 9 May 2002 15:28:54 -0400, Greg KB4NVD/R wrote:
> 
> >I have a few questions about what it is like to operate mode JA
> >on FO-20 & 29:
> >What kind of antennas will I need for TX and RX? Will omni's be
> >sufficient?
> 
> Yes, you can use omni's.  I'm using a pair of the M-squared Eggbeaters
> for up and downlink to the FO sats with pretty good success.  The
> limiting factor will be hearing yourself - I'm usually not quite as
> loud as the other stations in the QSO, but can most often hear my
> own downlink enough to tell that I'm on frequency. Adding a software
> doppler correction program (I use the W6IHG Radio Tuner for the
> Kenwood TS-2000 now) helps.. or you can use one of the hardware
> solutions.  Trying to tune for doppler and move antennas manually
> would drive someone crazy, quickly.. those birds move fast!
> 
> >What is the dopler like and how do I tune for it on a JA transponder?
> 
> The doppler on 435 is a killer.. most folks set their transmitter and
> tune the receiver on the FO sats.  I've got the ability  (with the software
> and the computer controlled doppler correction) to keep the apparent
> downlink frequency stable using uplink and downlink correction, but I've
> not heard anyone else that does that on the FO birds.
> 
> >How well are the satellites working right now?
> 
> They work quite well most of the time. Some short (10-30 sec) fades, but
> quite often there's only a couple of folks on the satellite.
> 
> >Is there many people on and what about some DX stuff like Carribean
> >islands, South American stations, VE, etc?
> 
> See above. Nope, not a lot of DX on the FO sats that I've heard. They're
> within range, but not too many people on them.
> 
> >My background is that of a VHF rover and an old timer RS-10 Mode
> >A operator. I have available for this project; KNWD TR-751 2m 25w
> >TR-851 430 radios, ARR preamp for 435.
> >If possible, I want to keep my antennas simple so I can take this show
> >on the road and operate portable from various grids.
> 
> That's certainly do-able. Mount the eggbeaters as far away from each other
> as you can and take off... should work well, as long as you've got very
> decent ears (add a good preamp to the 435mHz redeive chain... you'll be
> very glad you did)... and 100w omni up should give you more than enough
> signal into the satellites.
> 
> Good luck and see you on FO20 & FO29!
> 
> 73 Wayne N5WD
> 
> ---------------------------------------------------------
> R. Wayne Day, Licensed Paramedic  Fort Worth, Texas, USA
>      n5wd@earthlink.net      rday@northwest.k12.tx.us
> Health Science Technology Instructor/Clinical Coordinator
>       Northwest High School, Justin,Texas  Go Texans!
> -------------------- 73 de N5WD -------------------------
> 
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