diyAudio (
-   Tubes / Valves (
-   -   Help, what is this (Marconi 6204) ? (

tricomp 2nd April 2013 08:28 PM

Help, what is this (Marconi 6204) ?
1 Attachment(s)
This picture from an ebay auction.
What is it?
Seller claims 1/2 of a 6X5, more or less.
Sibley's Tube Lore doesn't know.
Neither does any RCA manuals I have.
Google is empty.
WHAT is it?



lazzer408 2nd April 2013 08:48 PM


tricomp 2nd April 2013 08:54 PM


Originally Posted by lazzer408 (

..and how do you know?
Any data available?



tricomp 2nd April 2013 09:21 PM

1 Attachment(s)
I have a Military Handbook covering pretty much anything in tubes over time.

The 6204 just isn't there, have a look.
Makes you wonder if it was ever in production and the ebay specimen is a prototype sample.



tomchr 2nd April 2013 09:21 PM

Perhaps you should try Bing... It comes up with the following:

TUBE 6204-MCN Marconi - Tetrode | Vacuum tube online

No data, though. But at least it shows as a tetrode.


tricomp 2nd April 2013 09:26 PM

Hi Tom,

Thanks, Google shows the same.
This doesn't prove anything, like the ebay auction stating it's a rectifier doesn't prove anything.
Have a look at the pdf-page above I pulled from the Military hand-book.
The reason why I'm interested is that if it's really a rectifier I would buy it.
I have planned a hi-gloss yellow chassis Marconi 6V6GT/G PP integrated stereo-amp with green hi-gloss xfmr-covers for the future.
The pale-blue octals would fit right in if they are indeed rectifiers.

...or is that over the edge...? :D



kevinkr 2nd April 2013 11:48 PM

Strange I have data for 6203 and 6205, but not 6204 - and this in a variety of Sylvania, GE and other tube manuals. Franks has no reference to it, even in short data or the Vade Mecum which is pretty comprehensive.

tricomp 3rd April 2013 03:02 AM

That, kevinkr is exactly what I mean.
I also have a lot of manuals on hand and no ref. to a 6204 in any of them.
Yet there can be no doubt that it exists looking at the picture and even the box has the number 6204 printed on it.


tricomp 3rd April 2013 11:13 AM

1 Attachment(s)
Page from old AVO-tester manual.
No such thing as a 6204.

Very, very strange...


kevinkr 3rd April 2013 04:22 PM

I will try to have a look at the charts on my Hickok 539B and in the manuals, but I suspect it will be the same story.

They might be worth having as a conversational curiosity, but even knowing what they are (and I don't.. lol) I would not design them into anything. There has got to be a reason why this number was assigned and never released into the wilds.. :p

All times are GMT. The time now is 11:45 PM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2