Rerurn to Romy the Cat's Site

In the Forum: Off Air Audio
In the Thread: A tube tuner? REL Precedent 646C
Post Subject: I do not touch the RF. Absolutely not.Posted by Romy the Cat on: 7/29/2008

 Paul S wrote:
Of course you will give this Grande Dame ('54 - '55 ?) a fair shot with some new parts, apropos?  Especially new caps?

I would certainly would be very interested if someone with RF knowledge would rebuild the REL circuit from scratch, using better contemporary part and better building methods, perhaps with some minor improvement of the REL’s ideas; however I will not be the person who will touch anything in the REL as it is now. I trashed the REL output stage. Whatever in there before the detector diodes is not sound but radio frequency and I have absolutely no knowledge how the RF parts are responsible for sound. There are explanations how the RF solutions effect reception characteristics but not sound, at least it not know to me.

All that I intend to do if to put better contemporary end of the detector and build-in a good op-amp buffer for MPX signal to drive my external stereo decoder. It might be an elegant idea to use the sockets for tubes V14 and V15 to build my own output stage but I never was able to make a transparent enough tube buffer.  If you still deal with Mike Zuccaro then ask him what buffer he used, unless he built into the REL a very sensitive decoder chip.

BTW, I changed today the detector diodes to regular 4pF silicone and the mixing resistors and the sound did got better, much less cotton-like. I weigh when the Schottkyes and the ap-amps arrive…

The Cat

Rerurn to Romy the Cat's Site