[hpsdr] IP3 >+50 dBm ?

[stoskopf at tri.net]

Chadwick in RadCom some years ago went into detail the need for better
receivers, and without digging the article out of many boxes, I think that
his conclusion was that we pretty well were there.

The present discussion seems to be comparing the TenTech Orion engineering
approach of making all the stages with similar strengths (or weakness) to
our hobby approach of making each stage a good as it can be, even if at
the present that stage is overkill.  None of us are doing this to shave a
few pennies off manufacturing costs.

I've got a 25 year old homebrew Martin type 160M on the shelf with a
Mini-Circuits RAY mixer straight from the antenna feeding a VMP-4 grounded
gate IF amp at 400 ma feeding one of Sherwood's gaussian filters and
Plessey chips for the rest of the ckts.  LO built around a BC-221 running
2 watts and attenuated down to match the mixer.  Each stage in a separate
die cast box. Except for the crummy AF AGC it probably is the stoutest RX
I have including the Orion I.  I never tried to figure out which was the
next weak link or cost as it ran rings around the commercial rigs of its
time.

Now if I can just get the Ubuntu screen resolution on the new PS3 set at
better than the default, I'll try to join the guys in a NEXT step in the
pursuit of the perfect RX.

N0UU




 1188363860.0