[amsat-bb] Re: down converter

Luc Leblanc lucleblanc6 at videotron.ca
Sun Mar 22 17:09:41 PDT 2009

On 22 Mar 2009 at 16:03, Greg D. wrote:

> Or modify one.
> I wanted an IF in the 300 mHz range, so that I wouldn't have to worry about interference from either a 2m or 70cm uplink. 
>I'm using an ICOM R-7000 all mode scanner for the IF receiver, so the odd frequency isn't a problem.  It was a fairly simple 
>matter to swap crystals on a Drake 2880 and change out one cap, to move the local oscillator to 2100 mHz.
>That puts our 2401.x mHz downlinks at 301.x  You might be able to push it far enough to get to 435.  You'd need to get the LO down to 
7,679.69 kHz (7.68 mHz), if my calculations are correct.
> Greg  KO6TH
I'm using a PCR-1000 for the IF receiver tuning 123.xxxMHZ on a AIDC 3733 downconverter and i don't get any interference from even with 50w 
on a 14 elements cross yagi on 145mhz uplink.

No filtering just the RG-59U plugged into the PCR-1000 and with the AFC button depress you have a nice doppler correction without any bell 
and whistle.

P.S. I am still struggling with the deep fades more noticeable on the south to north pass on the south portion and on the north to south on 
the south portion too.If he's spin stabilized there is something blocking the path under some angles.Probably a new Irish Leprechaun 
playing havoc up there...I'm guessing it is the same one who was on AO-40.

We will have to wait untill the next S downlink session to test our S band gear again. Now it's SSTV pictures time.


Luc Leblanc VE2DWE
Skype VE2DWE


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