85A2

[BTH K10A]

Clearing out some old valves and thought someone here might want a NOS one of these regulators.

http://i46.photobucket.com/albums/f120/emttsd15/IMG_1168-1.jpg

[Marco]

Price? ;)

Also, could I see the valve outside its box? Churz!

Marco.

[BTH K10A]

how does £5 inc. postage sound?

http://i46.photobucket.com/albums/f120/emttsd15/IMG_1169.jpg

[Marco]

Very good, just one thing, do you know if it's 50s, 60s or 70s vintage? I've got one that came in a black, blue Mullard (written in red) box, like this:


http://img11.imageshack.us/img11/9335/bcbdn2kkgrhqeokisezsk07.jpg (http://imageshack.us/photo/my-images/11/bcbdn2kkgrhqeokisezsk07.jpg/)


...and wondered which one would be the earlier version - do you remember where you got yours from? :)

Marco.

[BTH K10A]

Yep, a junk/antiques dealer in Rochester cleared out an old radio/TV shop about 5 years ago. There were lots of valves in a cupboard in a basement.

He knew I had valve hifi and contacted me, said he had a few boxes of them so I agreed to buy them unseen. When he delivered they were packed in fruit boxes and ammounted to two 8' high stacks. They've been in the cellar ever since. There were lots of goodies and some crap but the dozen ECC32's were a nice surprise as were a pair of STC 4300A's

Logo indicates 1970's I think. Code says R6L which would be made in Mitcham during December 1976.
The Logo on the valve is the same as that on the box

[Jonboy]

Nice find Andy

[Marco]

Hi Andy,

Ah, ok... I'll have a think, dude, as I was looking for a 1950s one. A fiver's a great price, but I've got about 6 or 7 of the buggers already (I use them as a voltage stabiliser in my Croft), so I'm not sure that I need another 70s one :)

Marco.

[Ali Tait]

300a's?? You lucky bugger! One of the best sounds I've ever heard was from a pair of 300a's.

[BTH K10A]

Hi Marco,

I'm not sure the 85A2 was around in the fifties. I might be wrong but I've never seen one with an early logo.

What you really need is one of these siemens cans for the stabiliser. :D Don't know if it will fit in you croft though. :scratch:

http://i46.photobucket.com/albums/f120/emttsd15/tube_85A2.jpg

Also remember s that the 85A3 takes about 300 hours before it reaches its optimum performance so swapping to frequently may not give the best results. Has a 10,000 hour life though

[Marco]

I'm not sure the 85A2 was around in the fifties. I might be wrong but I've never seen one with an early logo.



http://img856.imageshack.us/img856/2382/adv068.jpg (http://imageshack.us/photo/my-images/856/adv068.jpg/)

http://r-type.org/exhib/aam0046.htm From the article:


Type 85A2 was first introduced in 1950

;) Check out the one that the BBC had labelled from 1954!


What you really need is one of these siemens cans for the stabiliser. :D Don't know if it will fit in you croft though. :scratch:

http://i46.photobucket.com/albums/f120/emttsd15/tube_85A2.jpg


Lol!


Also remember s that the 85A3 takes about 300 hours before it reaches its optimum performance so swapping to frequently may not give the best results. Has a 10,000 hour life though

Indeed. I don't swap them often, but like trying different ones sometimes, and finding the best sounding ones... Do you think that the blue/black Mullard box the 85A2 I'm using at the moment was in, was earlier than your one in the red box?

Marco.

[BTH K10A]

Indeed. I don't swap them often, but like trying different ones sometimes, and finding the best sounding ones... Do you think that the blue/black Mullard box the 85A2 I'm using at the moment was in, was earlier than your one in the red box?

Marco.

Apparently they are from the same period but the red boxes have the script " valves and tubes for communications and industrial electronics" whereas the blue boxes just have "Mullard the master valve" and were for consumer sales. I don't know if the valves were specially selected for the red boxes, I somehow doubt it. I think it was more to prevent theft from the workplace as they could be readilly identifiable. I'ts a bit like the studios adopting the EMT Neumann diamond pin layout rather than the SME Ortofon square pin for their cartridges.

[Marco]

Ah I see - churz! I'll need to see if I can find a date code on the one inside the Croft next time I look...

Interesting though that the Beeb used them in the 50s. I wonder in what context? :)

Marco.

[BTH K10A]

Do you think that the blue/black Mullard box the 85A2 I'm using at the moment was in, was earlier than your one in the red box?

Marco.

Red Box was definitely for industrial sales / use.

This guarantee was in another red boxed Mullard and it's certainly different from those in blue boxes.

What may be interesting is whether the valve sold in the red boxes marked industrial and tecomunications were specially selected. It would certainly make sense for GPO use as their standards were quite strict. It's also not uncommon that the general public were sold the valves that did not meet military or special quality standards., or, to put it bluntly there were sold the crap.

http://i46.photobucket.com/albums/f120/emttsd15/IMG_1206.jpg

Given the valve to the wife and it's now on that auction site.

[Marco]

Hi Andy,

If you chuck in the guarantee leaflet (or tell me how much extra you'd like for it), I'll buy the tube from you! If this now needs to be done through eBay, PM me the link to the sale :)

Marco.