[amsat-bb] Re: VO52 questions.... Fri, 2 May 2008 21:29:26 -0700 (PDT)

John Kopala jkopala at gmail.com
Sat May 3 23:04:27 PDT 2008


I think that crazy tuning pattern boils down to this:  If the station you 
hear is not using doppler they will appear to be going up the band.  Then a 
station that is using doppler control may appear stationary or moving up the 
band depending upon how fast your doppler AND their doppler are updating. 
More frequent updates are better and eliminate a bunch of tuning.  I think 
the default is around 100 hz.  I use 20 hz.

For your own signal, I'm assuming that your are hearing yourself.  I often 
have to tune either the uplink or the downlink as much as 1500 Hz to match 
the uplink to the downlink.  You are right on the LSB up and the USB down. 
Don't give up, you are almost there.  Don't worry about the other stations. 
Pick a open spot and tune yourself first using the CAT Tuning window.  I 
believe I usually have to tune the Uplink UP.  Once you do it the first 
time, you'll get the hand of it.

Also, sometimes when I first select an SSB bird, the Downlink and Uplink 
frequencies will be a ways off from the frequencies shown in the CAT Tuning 
window.  If this happens, go to the up and down buttons just to the right of 
the Downlink and Uplink display, click the 20 up and then the 20 down.  The 
Downlink and Uplink should jump to the proper frequency.  This may have been 
caused by my CAT delay not being high enough, but I haven't observed whether 
changing that fixed it.

John
N7JK

From: asd asd <sunsetdialpad at yahoo.com>
Subject: [amsat-bb]  VO52 questions....

I have been trying for a week to get into the VO52 satellite and have some 
questions... I can hear people talking and have to constantly manually tune 
them in in crazy patterns. One persons doppler will go up and another will 
go down. It is like I am chasing people that are constantly changing their 
transmit frequency and does not fit a normal doppler change. Another thing 
is that I cannot tune myself in at all. It is like I am transmitting in the 
wrong sideband. I am recieving the downlink in USB and it is my 
understanding that the uplink is supposed to be LSB. The program I am using 
is SatPC32 that CAT tunes an IC910H into a M2 2MCP14 - M2436CP30 both with 
right hand polarization. Just trying to get away from the FM Birds and try 
some new ones and looking for some help to figure out what I may be 
overlooking or doing wrong.

  Thanks...

 



More information about the AMSAT-BB mailing list