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Re: {amsat-bb} 3731AA Downconverter Gain ?

On 15 Aug 2003 at 20:55, Peter Moscatt wrote:

> What is the typical gain for the 3731AA downconverter ?
> I would like to optimise my dish setup for AO40 and calulate overall
> performance given gain and line losses.
> Pete VK4CCV
Maybe some use -  I have a calamp 31881 (an older version than yours)
Has a new front end chip, the measured fiqures from a professional 
source is gain 39db noisefiq 2.5db.
With these numbers I find ANY co-ax from the dc will do I am using 
30feet of 70ohm tv cable !!!. 
dc is mounted either at the feed or I use a 17db gain .6db noisefiq 
preamp right at the ant 2feet low loss 1/2 inch co-ax to dc
ron vk5akj (acheyJ)

BTW I see from time to time offset dish setups with the arm on top 
REAL BAD idea the whole purpose of an offset dish is to aim the feed 
"spillover" at the cold sky NOT the warm earth

Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
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