[amsat-bb] Preamp source

[Edward R Cole]

The problem is hams expect things to cost near nothing and prices 
never to increase.

ARR Gasfet preamps* sold for years at $79.xx yet cost of material are 
rising.  Last I checked they still use the mgf-1302 yet where is one 
able to find one?  The mgf-1302 provides a reliable 0.5 dBNF and 
about 22 to 25 dB gain.

PGA-103+ appears to get 0.6 dB gain with about 15-18 dB gain

If you are a small mfr you do not get the volume parts discounts so 
materials represent 80% or more of your price and return on labor 
does not justify working.  When I built DEMI transverter kits for 
$100 in labor I made $100/16 = $6.25 per hour.  I finally quit as I 
thought about doing something else in my retirement.

WA2ODO has quit the preamp business (age & health).  For $85-110 you 
don't make much for your time once the cost of materials is paid.

*non RF switched versions

Spend $95 each for two coax relays and add to $79 and see how cheap 
you can make a switched one for yourself.  Yes, some pcb relays can 
be used if you can figure out how to eliminate inherent 
inductance/capacitance.  RF-sensed switching preamps are still "hot 
switched": RF arcs across the contacts as the relay closes.  Only 
with a switched preamp under sequenced dc control is the device truly safe.

73, Ed - KL7UW
   http://www.kl7uw.com
Dubus-NA Business mail:
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