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Old August 29th 05, 04:19 PM
Pete KE9OA
 
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I used to have a few of them, but the collection grew to the point where I
don't have the time for play with them all. Right now, I am working on
another receiver. I just picked up an Icom R7100. The 51.2MHz reference
crystal had drifted down in frequency over the years to the point where it
could not be warped on frequency with the trimmer capacitor. I replaced the
trimmer with a better grade microwave trimmer and solved the problem.
The original trimmer had a range of 2 to 12pF......I replaced it with a 1.3
to 14pF unit and was able to warp the oscillator to the correct frequency.
The off-frequency crystal caused a few problems. First of all, it is divided
down to 12.8MHz to act as a frequency reference for the synthesizer. Next,
it is multiplied by 5 to 256MHz for the 2nd LO injection for the 512 to
1000MHz range........finally, it is multiplied by 15 to 768MHz for the 2nd
LO injection for the 25 to 512MHz range.
I still need to check the 3rd LO frequency of 10.245MHz and make sure it is
on frequency and adjust the BFO injection frequencies for the SSB modes.
A relatively complex receiver, but it seems to be easy to work on. I forgot
that you had an AOR unit. I haven't gotten to play with mine for awhile, but
the 7030 is a decent receiver. My favorite thing about it is is menu
structure. With all of those hidden functions, it is like having a castle
with all kinds of rooms to explore.

Pete

I figured the Palstar R30 would sound good after reading about the audio
output stage and other specifications on the filters.

Don't know about the collecting thing. I like to use what I own. I have
three table top radios. The 7030+ is next to the bed and the other two
are on a shelf in the office. I have one on Matt Drudge and the other is
on NZ right now. I have a speaker cable going down stairs so I can
listen while puttering in the kitchen. Today I was listening to Japan,
Netherlands and Australia while baking my latest disaster in the kitchen.

--
Telamon
Ventura, California