[Drake] Tube tester wanted

[Garey Barrell]

Joe -

You, and your Drakes, would be better served by spending the money on 
a set of replacement tubes.

It's best to try the new tubes one at a time, in a properly operating 
radio, as not all 'new' tubes are good.  Once you have a 'known good' 
set of tubes, any time you think your radio may not be operating up to 
par, start subbing appropriate tubes.  If no improvement, putthe 'old' 
tube back in and your good tube back on the shelf!  Once a radio is 
tuned up and operating normally, there are very few tube 'failures' or 
'weaknesses'. There are a LOT ofgood tubes tossed out because of tube 
testers and those who think they're like spark plugs and replace them 
all at once!  :-) 'Weakness' is a result of Cathode depletion, and 
modern tubes have LOTS of cathode coating.  PA tubes are the only ones 
that will eventually 'wear out' in normal use.  Run them off resonance 
however, and they'll wear out in a hurry as the Cathode coating get 
blown off by amperes of current!!

Testing them at 60 Hz in a tube tester only remotely infers how they 
would work at RF.  A tubetester is useful if you have a box of 1000 
tubes of unknown condition and you want to sort them out!

73, Garey - K4OAH
Glen Allen, VA

Drake 2-B, 2-C/2-NT, 4-A, 4-B, C-Line
and TR-4/C Service Supplement CDs
<www.k4oah.com>

Joseph Trombino, Jr wrote:
> 'm looking for a Hickok 752A tube tester in working condition.
>
> A Heathkit TT1A tube tester could work for me as well.
>
> If anyone out there has one of these critters for sale please let me know.
>
> Trying to keep my Drake gear in working condition and a good tube tester sure would help in this endeavor.
>
> Many thanks for any assistance.
>
> 			73, Joe W2KJ
>