Thermionic valve construction - UK Vintage Radio Repair and Restoration Discussion Forum

kellys_eye · 10th Apr 2016, 11:01 pm

Does anyone know of a website where I can get images of genuine thermionic valves (some of the more common versions, diode, triode, EL83 etc) in their 'de-constructed' state? Hopefully with dimensions?

I've found many sites that show the basic working construction but nothing that shows the actual parts in a dis-assembled form that is readily identifiable.

Reason for wanting the info - I would like to create Sketchup drawings of typical devices such that each part is drawn as a separate 'layer' making it possible to view the parts from the 'inside to the outside' and also rotate the drawing to view it from any angle, zoom in etc etc.

Ok, no practical application for what I'm intending to do but it may prove to be a reasonably good looking (maybe fun?) educational tool.

TIA

Dave

M0FYA Andy · 11th Apr 2016, 9:02 am

The parts used to build an EF80 are shown here -

http://www.r-type.org/articles/art-019.htm

I don't know whether Mullard produced similar items for other valves, I have one of these EF80 'kits', but have never seen any others.

Andy

kellys_eye · 11th Apr 2016, 10:42 am

That's a good example, thanks Andy. I can extrapolate the dimensions of the internal parts from the known size of the finished envelope.

Even now I am amazed at how intricate the construction was and the practical uses to which the finished product was put. Far from being 'old technology' it is just disappointing there aren't more in use today!

I'll do a trial construction in Sketchup using the details in your link.

mark pirate · 11th Apr 2016, 12:26 pm

This film shows component parts and assembly.
https://www.youtube.com/watch?v=dErs...&nohtml5=False

Mark

11th Apr 2016, 2:57 pm

Break a non working one and have a look?

valvecollector · 11th Apr 2016, 3:06 pm

I have a couple gone to air I can cull if you want some measurements and pics.

Jeremy

M0FYA Andy · 11th Apr 2016, 3:21 pm

For an EF80 I wouldn't even worry about breaking a working example - put two in a drawer and look next day and there will now be ten!
Andy

11th Apr 2016, 4:22 pm

Put a request into 'parts wanted' for dead valves. No need for expensive packaging, but I think they will all survive. Seems a shame to wreck a working valve, even if it is one of the 'lowly' types. EF80's work well at audio to (oops, that's put the price up from 1p to 10's of pence).

10th Apr 2016, 11:01 pm	#1
kellys_eye Octode Join Date: Jan 2014 Location: Oban, Scotland, UK. Posts: 1,096	Thermionic valve construction Does anyone know of a website where I can get images of genuine thermionic valves (some of the more common versions, diode, triode, EL83 etc) in their 'de-constructed' state? Hopefully with dimensions? I've found many sites that show the basic working construction but nothing that shows the actual parts in a dis-assembled form that is readily identifiable. Reason for wanting the info - I would like to create Sketchup drawings of typical devices such that each part is drawn as a separate 'layer' making it possible to view the parts from the 'inside to the outside' and also rotate the drawing to view it from any angle, zoom in etc etc. Ok, no practical application for what I'm intending to do but it may prove to be a reasonably good looking (maybe fun?) educational tool. TIA Dave

11th Apr 2016, 9:02 am	#2
M0FYA Andy Nonode Join Date: May 2007 Location: Preston, Lancashire, UK. Posts: 2,483	Re: Thermionic valve construction The parts used to build an EF80 are shown here - http://www.r-type.org/articles/art-019.htm I don't know whether Mullard produced similar items for other valves, I have one of these EF80 'kits', but have never seen any others. Andy

11th Apr 2016, 10:42 am	#3
kellys_eye Octode Join Date: Jan 2014 Location: Oban, Scotland, UK. Posts: 1,096	Re: Thermionic valve construction That's a good example, thanks Andy. I can extrapolate the dimensions of the internal parts from the known size of the finished envelope. Even now I am amazed at how intricate the construction was and the practical uses to which the finished product was put. Far from being 'old technology' it is just disappointing there aren't more in use today! I'll do a trial construction in Sketchup using the details in your link.

11th Apr 2016, 12:26 pm	#4
mark pirate Dekatron Join Date: Mar 2008 Location: Worthing, West Sussex, UK Posts: 5,182	Re: Thermionic valve construction This film shows component parts and assembly. https://www.youtube.com/watch?v=dErs...&nohtml5=False Mark

11th Apr 2016, 2:57 pm	#5
Guest Guest Posts: n/a	Re: Thermionic valve construction Break a non working one and have a look?

11th Apr 2016, 3:06 pm	#6
valvecollector Hexode Join Date: Jul 2003 Location: Leeds, West Yorkshire, UK. Posts: 430	Re: Thermionic valve construction I have a couple gone to air I can cull if you want some measurements and pics. Jeremy __________________ Virtual Valve Museum https://valvecollector.uk/ Jeremy, M0RVB

11th Apr 2016, 3:21 pm	#7
M0FYA Andy Nonode Join Date: May 2007 Location: Preston, Lancashire, UK. Posts: 2,483	Re: Thermionic valve construction For an EF80 I wouldn't even worry about breaking a working example - put two in a drawer and look next day and there will now be ten! Andy

11th Apr 2016, 4:22 pm	#8
Guest Guest Posts: n/a	Re: Thermionic valve construction Put a request into 'parts wanted' for dead valves. No need for expensive packaging, but I think they will all survive. Seems a shame to wreck a working valve, even if it is one of the 'lowly' types. EF80's work well at audio to (oops, that's put the price up from 1p to 10's of pence).