[R-390] CV-157

[Bill Hawkins]

What Nick said and some caveats.

The two rack panels are joined by a thick cable with no connectors.
You could separate them if you have infinite patience and time.

The missing power transformer is a deal breaker if you want to
restore it. Quite unique.

Speaking of unique, the mixer tube that brings 455 KC down to 100
is rare. Don't remember the number, now. The creep that sent mine
had stuffed it with arbitrary tubes and put it in a single cardboard
box with peanuts. The box was broken, peanuts mostly gone, and
something heavy had smashed the 100 KC transformers in a corner
of the upper chassis. Never did get it working, someone else's
problem now. Lost several hundred dollars learning that lesson.
Shipper wouldn't pay because of the crappy packing. Guy who sold
it wasn't rational.

The auto-tune mechanism requires some carrier in the SSB signal,
which is unlikely these days. The 157 was part of a system that sent
eight channels of TTY data, four on either side of the carrier. 
Good luck finding a signal like that in today's digital comm.

Other than that, it's a real piece of high-tech history.

Bill Hawkins


-----Original Message-----
From: Nick England
Sent: Monday, October 15, 2012 7:29 AM
To: polaraligned at optonline.net

Well they are interestingly complicated. And they certainly are boatanchors.
Even without the pwr xfmr it'll be 100 lbs. 
I really enjoyed restoring mine and learning all about it. Your friends will
definitely be amazed watching the AFC motor do its thing. And being able to
do simultaneous USB and LSB is kinda neat. 
But practically speaking the CV-591 is much much easier to restore and
operate and move around. I have both hooked up and don't really hear any
difference in voice quality. 

The CV-157 is a star because of the AFC and ISB capabilities but that's not
anything you can make use of on the air today. 

Value? I think I paid $100 ea for the two I have. One was local and the
other cost me another $100 in shipping. Basically the value to the other guy
is what he could get parting it out. 

If you like technical challenges and enjoy learning new circuitry it is a
great project even if the CV-591 is much more practical. 
My opinion for what it's worth. 
Nick
(phone email acct)