[Drake] TR-4 question - solved

[Steve Thompson]

On Tuesday 08 June 2004 03:24, Jerry Kincade wrote:
> Call off the dogs, and thanks for all the suggestions. As most suspected,
> it turned out to be a neutralization problem after all. Found the neut cap
> fully meshed - don't see that too often - cranked it out to 45 degrees for
> a starting point (tip of the hat to Dave Harmon, K6XYZ), and started
> neutralizing on 20m vice 10m. She came in pretty as you please at about 15%
> meshed. Also checked all three PA cathode resistors (supposed to be 15 ohm
> 1W, 5%), they ran from 16.8 to 22 ohms. Hmmm... 5% would be +/- 0.75 ohms.
> Ha. Will change them out with 2 watters (do they have to be carbon or can I
> get away with "flameproof" metal film?) 
Unless you have a driving desire to preserve the originailty, I'd suggest that 
you never use carbon resistors in anything these days. Metal film are much 
more reliable. Their long term stability is excellent and all the brands I've 
used (professionally) can take serious overload without changing value - I've 
run some to the point where the colour bands are totally burned off, and they 
are still within 1%.

I'd be surprised if changing them required fresh neutralising, but please let 
us know if you do it.

Steve