Colossus - Valves

[n_r_muir]

Hi,

Some time ago on one of the articles on Colossus I saw this appeal for valve types that they need.

The Colossus Rebuild
Top priority: 807
Also needed: EF36, EF37, EF37A, 6J5, 6V6, 6K8, 807, GT1Cs


Ross

[jim_jobe]

Cheers Alan.

It is incredible to think that a few 'loony engineers' and glass bottles saved so many lives. A quick bit of mental adding up and it's about 10 to 100 per valve.

[Sean Williams]

Just a short interlude..... Sending valves for Colussus to the BP mansion house is not a good idea.

Try sending to The National Museum of Computing instead - both on the same site, but two completely separate organisations.....

[Alan Stepney]

It would be useful if someone could get an updated list of what they require.

My list is woefully out of date, and I suspect their requirements change quite frequently.

[jim_jobe]

I've emailed them for a list and will post it when it arrives.

[Jeremy M0RVB]

Just out of interest CV358 does not appear in the 1944 CV Register and has no details (i.e. a blank line) in the 1946 one. CVs were being introduced all that time so it is possible Colossus used 'ordinary' types like the valve request suggests. EF37 is not listed in the cross-reference table in either release.

Colossus is one of those things I really want to go and see! One day...

[DangerMan]

Some valves seemed to get a lot of numbers for the same item during wartime, maybe to confuse the enemy (?), and the CV numbers don't seem to be in any particular date order.
EF36 was the predecessor to EF37 and EF37A, and was also known as VR56 (British air force), in which guise it went to war.

Other military numbers for the same valve seem to be CV1056 and NR49, and CV1404 also shows up on R-Type.org!
I wonder whether their registered dates show anything.

Colossus is one of those things I really want to go and see! One day...

You will not regret it, the new display lets you walk all round it, no glass or stuff in the way merrily a simple wooden barrier 3 foot high, and you can feel the heat from all those valves too. There is an odd entrance fee structure though x for Bletchly, an additional y to see Colossus (at the computer museum, if the museum per se is closed) or z for the computer museum alone which includes Colossus. Err...

[Heatercathodeshort]

The Mulard 'Red E' series valves did not include a single diode with a top cap. It would probably have been a EC33 had it been produced and as they were producing the double diode triode EBC33 it would have been odd to produce a single triode with a top cap. I seem to remember valve requests for Colossus years ago and that list did include an incredible number of 6SN7's. Many thousands of these were sent over on Lend/Lease during WW2. There was nothing special about the valve and having many applications may not have arisen suspicion at that time. John.
PS. Thinking about it they may have been EF39's strapped as triodes?

[Top Cap]

There are some wonderful videos on YouTube about Bletchley Park but for Colossus fans you must see this one. It gets really interesting at 13:30!

https://www.youtube.com/watch?v=5nK_ft0Lf1s

[Heatercathodeshort]

The red valves appear to be Octals. They can only be EBC33s or EF39s by size alone.
Interesting to note that they used GEC thyratrons and not the less reliable Mazda T31/T41. John.

[Radio Wrangler]

From experience with phone exchanges and repeater amplifiers, Tommy Flowers and co would have been very well informed on what was reliable and what wasn't.

I assume they also wanted to use valves which could be ordered in quantities by several different telephone equipment makers each making different assemblies so no-one saw a bigger picture of what was being assembled.

Large quantities of military valves going to unlikely places might be noticed and they were wary of the possibility of espionage. After the war it was found that the anti-spying efforts had been very successful, but they couldn't have known that at the time.

Thyratrons cropped up in all sorts of places. I made a VMOS circuit to replace 2050 thyratrons in the Seeberg jukeboxes which a friend of my father's used to hire out.

DAvid

[Nicko]

Originally Posted by Alan Stepney

..I was able to supply them with many dozens of assorted valves for the rebuild of Colossus and for the EDSAC project.

I supplied them with some rare dekatrons for the WITCH project and never got so much as an email "thanks"... others in the TCA had the same experience.

Never again.

[ukcol]

I'm sorry to hear that Nicko, I had quite a different experience; I supplied a relatively small number of EF36s for the Colossus project and received a personal thank you letter from the late Tony Sale.

Nicko,

You get thanks from me, I have seen the WITCH working, bloomin' brilliant, and spoke to one of the restorers, he was very enthusiastic. Seems a shame you didn't get a thank you.

I did have the great pleasure of meeting Tony Sale when seeing the Colossus once, lovely chap, now where did that hour go!

[Phil G4SPZ]

Having read this thread, I e-mailed them to offer four NOS 807s which they've confirmed are still wanted. Unfortunately, they will neither reimburse postage costs nor travelling costs. Nor, apparently, do they offer any other inducements such as free entry to the museum or the Park.

As Bletchley is a long and expensive journey by car or train from Worcestershire, and knowing the cost of posting a large protected box of delicate valves, I find their approach rather surprising. It may limit the number of valves they are being offered; whilst many people would happily donate surplus valves to such a deserving cause, how many are prepared to be out of pocket as a result?

My 807s are safe with me till they change their approach, or need them so badly that they'll pay the postage charges! That said, if the FCS could help, that might work...

I met the late Tony Sale on a couple of occasions, and what an interesting chap he was.

[jim_jobe]

Here is the reply I got from Bletchley today:

Hello Jim,

Thank you for your donation offer.

The list of valves needed for Colossus and WITCH can be found here: http://www.tnmoc.org/news/notes-museum/valves-attic

We also have the EDSAC replica project who's valves are detailed here: http://www.tnmoc.org/special-project...-edsac-project

Your box of 50 EA50s would be welcome for EDSAC.

Please send to the following address, marked for the attention of The Donations team. Also please label as "fragile valves" and pack well with bubble wrap / newspaper etc so it has a good chance of arriving intact.

The National Museum of Computing
Block H,
Bletchley Park,
MILTON KEYNES
MK3 6EB

Please let me know when you have posted them and if you have included any additional valves to the EA50s. Also please keep any additional valves to a small selection as we have a shortage of storage space at the moment.

Regards,

Peter Vaughan
TNMOC Volunteer

[Phil G4SPZ]

The same chap made it clearer to me, saying:

"Thank you for your donation offer. As we have had a high DOA failure rate we will accept any 807 valves that are offered.

As we don't have the resources to collect donations or cover postal/transport costs we have to rely on the donor to get items to us in some way. Are you able to post them or deliver them in person?

If by post, please send to the following address, marked for the attention of The Donations team. Also please label as "fragile valves" and pack well with bubble wrap / newspaper so it has a good chance of arriving intact. If delivering in person when do you hope to visit? Opening days/times can be found on our website; www.tnmoc.org/visit but we will require prior notification so someone is available to receive them."

Phil

[tis your junk]

Here is an idea

It saddens me a great deal to read this thread and of the poor response people of had from the two projects requiring valves. However, last year I met Dr Andrew Herbert who is I understand one of the leads on the EDSAC project and asked him if there was anything I could help him with?

His request was for valves but unfortunately I have none of the types he asked for - but here is something I can help with.
It so happens that I have to go to Betchley Park in March and (probably) May next year (for reunions/meetings) and I would be more than happy to fill my car with any valves/gear people may be be willing to donate.

What I propose is that as I usually attend the BVWS auctions if people could get them to me there I'll deliver them to BP.

Having said that I won't be able to make RWB this weekend but intend to be at Harpenden in March and the NVCF – which should give you time to get stuff sorted.

So any takers?