[Hallicrafters] HP VTVM's

[David C. Hallam]

Hi, thanks for the information about the 410C.  Actually some models of the
410B used the EA53 and that is what mine has.  HP must have anticipated
using either tube as there is a voltage adjustment to set the filament
voltage to the correct value for the diode in use.

73
David

-----Original Message-----
From: J. A Call [mailto:w7ksg at juno.com]
Sent: Friday, October 07, 2005 8:48 AM
To: dhallam at rapidsys.com
Cc: hallicrafters at mailman.qth.net
Subject: Re: [Hallicrafters] HP VTVM's


The tip probe will work on either  but the diode tube will not work
satisfactory because the diode tube from a HP410B is a  2-01C with a 5
volt filament, and the diode tube from a HP410C is a EA53 with a 6v
filament.

J
W7KSG