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Re: GRRRRRRRAAAAAAAHHHHHHHHGGGGGGGGG



Tim,

You have gotten lots of advice and I will probably duplicate it somewhat.
When AO-51 was first launched many of us wanted to copy the 9600-baud
telemetry beacon (this was before it was open for QSO's).  It was
determined that to get good reception you should not use a 5/8 whips or
dual-band whips.  It was recommended to use a 1/4 wavelength 2m whip over a
ground-plane (it works perfectly as a 3/4 wavelength whip on UHF).

I tried that with RG-213 (same as RG-8) to my FT-847 receiving on UHF.  It
did not work.  When I added a preamp it worked gang-busters!  As others
have stated AO-51 is not as strong as UO-14 or AO-27.  The long run of coax
before your IC706 is destroying your receiver noise figure due to the cable
loss.  Most commercial rigs have poor NF, in the first case.  The reason an
HT works (sort-of) is because the antenna is directly connected to the
radio and you do not havee the long coax run.

The simplest idea to verify this for yourself is to make a simple 1/4
wavelength whip or simple dipole and take the radio outside with antenna
connected with say 6-foot of cable.  You should be able to hear something
if there are QSO's going.

Really, for a home set up with roof-top mounted antennas you need a preamp
on UHF and a separate VHF whip to transmit on.  I am not familiar with the
IC706 to know if it has separate VHF and UHF antenna jacks.  If not then
maybe someone will relate how to do this.  I will not get into it.

GL and 73's
Ed - AL7EB

At 11:33 AM 1/25/2005 -0500, Timothy A. Holmes (W8TAH) wrote:
>Hi Folks:
>
>I am experiencing extreme frustration trying to hear AO-51
>
>Let me describe my setup which, I realize is not great for satellite 
>work (which is why I'm only trying to hear the blasted thing)
>
>Radio - IC706MKII
>Antenna 5/8 wave Bottom loaded groundplane at about 15 feet
>the only pre-amp I have is the one in the radio, and the COAX is basic 
>RG -8 i think
>
>
>I have been trying off and on to hear AO51 -- even just a gradual slight 
>silencing of the static would make me happy just to know I can hear it.  
>I mean guys are working the thing with HT's and Rubber duckies without 
>any trouble, and I used to use the same antenna to listen to UO 14 on my 
>vx5R.
>
>Last Night about 9:30 or quarter to 10 -- I dont have my numbers in 
>front of me, I was listening from 435.290 to 435.310 during a 69 degree 
>pass here in the cleveland area and I heard nothing. My keps are only 
>about 2 days old, I use nova and just had it do an automatic download 
>from whereever it defaults to to get them (celestrack I think). I didnt 
>see anything on the schedule page about the spacecraft being off.
>
>I really dont know where the problme is.  I had just used the radio and 
>antenna system earlier in the night for a net, so I know that its all good.
>
>Please throw some suggestions out here, I know I really dont have a 
>prayer of making it into the spacecraft without el-az antennas and true 
>full duplex, but I would think that I should be able to at least here 
>some of the downlink from it.
>
>Thanks 
>
>TIM
>W8TAH
>----
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