Xmas present to myself

[Vintage_RC]

Amongst my various interests I collect valves, mainly early and pre-broadcast era but also ones with visual appeal. I have just added an impressive valve to my collection, an STC 4212E. I have attached a photo of it alongside an R-valve and it's big, too tall for the cabinet I use for display.

[AndyWithStuff]

Thats really quite sculptural, I can see the aesthetic value of that, its difficult to tell how big it is with no size reference but going on the wall tiles I'd guess 2 feet?

[line sync]

That's a very impressive valve , I like it.

Robin

[Red to black]

That truly looks both a feat of engineering and a work of art I am suitably impressed

[Vintage_RC]

Originally Posted by AndyWithStuff

Thats really quite sculptural, I can see the aesthetic value of that, its difficult to tell how big it is with no size reference but going on the wall tiles I'd guess 2 feet?

There's an R-valve next to it to the right as a means of judging size. It is so much larger than the R-valve it is easy to miss it!

[Vintage_RC]

This is part of the description on the Science Museum website (they have one in their collection) :-

"STC 4212 E triode valve from Daventry short-wave transmitter, made by Standard Telephones and Cables Limited, England, 1925-1970.

This valve was taken from the first short-wave radio transmitter to be installed at Daventry in 1932"

['LIVEWIRE?']

I thought that might be a transmitting Valve, Alan.

[Herald1360]

https://frank.pocnet.net/sheets/125/4/4212E.pdf

[ionburn]

A good specimen and lovely idea. I cannot see her indoors accepting it though LOL

[David Simpson]

To Alan & any other special valve enthusiasts - I put out a lot of Forum thread info on an STC4212D back in 2015(25th Sept. "NOS STC4212D For Sale") & (7th Oct. "Testing the STC4212D Triode").
It was eventually flogged on eBay, but not for £500, but still for a fair wack. An amazing big rare valve & I enjoyed building the one-off testing rig.

Regards, David

[Vintage_RC]

I took a chance when purchasing the STC 4212E as the seller listed it as having a small misty area on the inside of the envelope which probably put many potential buyers off as they might be suspecting loss of vacuum. Also I asked if the filament had continuity but the seller (who turned out to be a very pleasant lady) had no way of testing it. I ended up getting it at her opening price of £50, on arrival the misty area was where the getter had be fired and the filament was good, in fact the valve looks new and unused. I doubt I will try it in operation but it must be impressive as a bright emitter with a filament rating of 14V at 6A (ie 84W!). There is a short video of one in a high power audio amplifier her:-
https://youtu.be/8LUIeZJEoAk

[Vintage_RC]

Just took a look at your example David, it looks as if it had a magnesium getter which is unusual for these valves, perhaps a late example as they were made over a very long period.

[HamishBoxer]

I had one of these valves in mint condition but never seen again after house move along with other things.

[G0HZU_JMR]

When I was a student we spent some time playing with real comms/radar equipment and I can remember seeing inside a Marconi Commander HF transmitter. Inside was a huge transmitting valve and it looked fantastic. I wish I could have taken a picture because my memory of what it all looked like is quite fuzzy now. I only had a few seconds to look inside.

Also, in my first job at Marconi I can remember looking inside the boxes of spares in the transmitter huts at Great Baddow. One of them was hut 37 if I recall correctly. There were some huge and very pretty valves carefully stored in crunched up paper inside wooden boxes. I'm not sure if they were RF valves or something to do with a modulator but they were very big and very beautiful. Hopefully they have been looked after because I suspect that the transmitters and also the huts will be long gone by now.