In a previous post, I professed that +20dbm from a preamp shouldn't be a big
deal. Somebody responded "so do you have this stuff laying around the
shack?"
I have been examining the National (formerly Com Linear) Variable Gain
Amplifier known as the CLC-522. It purports to be a 0 - 40 db variable gain
op amp that operates up to 165 mHz of usable bandwidth. It is a nifty
design and a $6 part. It has a typical noise floor of -152dbm. The data
sheet (if you can believe it) shows a -1db compression point (at maximum
gain) of about 18dbm, which should be quite usable on topband.
I have several concerns. 1) The inputs (very high impedance) may be very
sensitive to storm damage when hooked to a flag or pennant, which is my
goal. and 2) I want to try the 14 pin DIP version of the part to make storm
damage easier to repair than the 14 pin SOIC version (surface mount)--is 40
db of gain out of a DIP part either realistic or needed? (The Pennant has a
gain of -30-35dbi on topband)
Thanks for the bandwidth
Ford-N0FP
ford@cmgate.com
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