-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Richard Solomon
Sent: Sunday, January 26, 2020 4:33 PM
To: TekScopes <TekScopes@groups.io>
Subject: Re: [TekScopes] TEK514 needs new 5V4G tube

This may be blasphemy, but you
could replace the rectifier tube with
a couple of diodes.

You may need a small resistance to
adjust for the lower voltage drop in
the diodes.

73, Dick, W1KSZ

On Sun, Jan 26, 2020 at 4:34 PM Roy Morgan <k1lky68@gmail.com> wrote:

Steve,

I would strongly suspect a shorted filter cap in that supply.

If you have an external variable B+ supply, bring the voltage up VERY
SLOWLY at the tube cathode while monitoring the current. (Scope power
off)

Roy Morgan
K1LKY Western Mass

On Jan 26, 2020, at 6:10 PM, Steve Hendrix
<SteveHx@hxengineering.com>

wrote:

Okay, it's a "valve" for our limey friends!

... One rectifier tube right next to that monster power transformer

started getting extra hot within seconds of power-on, and then started
arcing and making a nice arc lamp. ...

--
Dennis Tillman W7PF
TekScopes Moderator