[Amps] Collins 30L-1 / 572's B

[Don Nesbitt]

I've been restoring and repairing 30L-1's and S-Lines
since the early 70's.  The only advantage to using
572B's in the 30L-1 is the higher plate dissipation of
the 572B - and that "may" be an advantage over the
long haul.  As others have stated, in order to realize
an increase in output, you'd have to increase the
plate voltage, etc, etc.  In my opinion, that's just
not worth the effort in this amplifier!

In the 30L-1, the 572B is a "drop in" replacement
requiring no modifications, etc - now, the purest will
likely argue here that the "Tune" indicator must be
reset using a good scope and a two-tone test generator
- but - lab measurements confirm that the difference
is for all practical purposes negligible - besides
which, in the "real" world, most people that I've
dealt with don't even use the "Tune" indicator, they
just tune for maximum smoke!

I do run 572B's in two of my personal 30L-1's (811A's
in my other two) - but - the difference in price
between the 811A and 572B not withstanding, if you've
already got some 572B's drop them in and go knowing
that you have an extra bit of plate dissipation.  If
you have a good set of 811A's already in your 30L-1
and would have to go out and buy a set of 572B's, save
your money!  Have fun, 73 es gud dx  --don n4hh


		
__________________________________
Do you Yahoo!?
Yahoo! Mail - 50x more storage than other providers!
http://promotions.yahoo.com/new_mail