In a message dated 97-02-26 18:34:20 EST, k0wa@southwind.net (Lee Buller)
writes:
<<
Several years ago, a CQ magazine writer extolled the virtue of the Sylvania
or Amprex 3-500Z. he said it had heavier graphite on the plate and a
different pate design which allows for more power dissapation. He also
swore that they sounded better over the air.
Has anyone any comments on this? Isn't a 3-500Z just that? >>
That article was not so accurate. It told people to replace tubes after every
so many hours because the "sound better". IMHO, thats bad advice.
The dissipation is identical between the tubes. The thicker graphite anode
has longer thermal lag, but is more prone to outgassing. I find no real life
difference unless the tube is subjected to large short duration overloads,
in that case the graphite anode is better.
Eimac graphite anode tubes are about ten bucks more than the moly anode
tubes.
73 Tom
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