Amps
[Top] [All Lists]

Re: [Amps] PL172 (8295)

To: chris@g3vbl.co.uk
Subject: Re: [Amps] PL172 (8295)
From: Alek Petkovic <vk6apk@bigpond.com>
Date: Sun, 07 May 2017 07:44:20 +0800
List-post: <amps@contesting.com">mailto:amps@contesting.com>
A 1kV megger will give you an immediate indication if there is any leakage.

I use it on old tubes. I run them in a burn in jig which applys heater volts and blows air through the tube. Some of the old Russian tubes take a week to get to the stage where there is no leakage indicated with the megger. At that point, they are good to stick into an amplifier and run at full steam.

You don't really need a hipot tester. The megger is fine and its cheap.

Alek
VK6APK

On 6/05/2017 10:11 PM, Chris Pedder wrote:
For the last 37 years my Hallicrafter HT33A has been sitting on the floor
in the garage with an 8295A (Ceramic) fitted. I have a pair of 'new in the
box' PL172s one of whose boxes is still sealed. Packing date was 6/67 so
that's almost 50 years.
I suspect that the glass seals will have leaked but is there anyone with
experience of these tubes after such a long period of time. If I were to
construct a hi-pot device, what sort of values should I expect from a
'good' tube? Thanks.

Chris G3VBL
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps


--
From sunny Binningup
Our new house.
https://17coronation.wordpress.com


Family Businesses:
SP Electrical. www.spelectrical.net.au
The Velvet Fox. www.facebook.com/TheVelvetFox
Smart Design Electrical. 0417 602 032
Perth Interiors. https://www.instagram.com/perthinteriors/


---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps

<Prev in Thread] Current Thread [Next in Thread>