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-   -   EMI Valve Scope Type B Amplifier - Free to a good home (https://www.vintage-radio.net/forum/showthread.php?t=158593)

knobtwiddler 3rd Aug 2019 1:57 pm

EMI Valve Scope Type B Amplifier - Free to a good home
 
1 Attachment(s)
Hi,

I say 'scope', but am not 100% sure that's where this plugin is from. I found it in a skip on the way to work recently. Alas, the person who dumped it had removed the valves.

Free to a good home.

DHL delivery will be 10.99. You can send a pre-paid label if you'd prefer.

Diabolical Artificer 4th Aug 2019 1:24 pm

Re: EMI Valve Scope Type B Amplifier - Free to a good home
 
Sure this isn't off a mixing desk or maybe a metering application on a mixer? If it is some folks go nuts for this kind of thing.

Andy.

knobtwiddler 6th Aug 2019 11:34 am

Re: EMI Valve Scope Type B Amplifier - Free to a good home
 
LOL! That was what went through my head when I saw it in the skip on the way to work (I once knew a guy who found an ARP synth in a skip, so I thought Christmas had come early for me!). I got it to work, but on the way popped into my friend who's a valve gear afficianado. It transpired that he'd already seen the EMI unit that morning and had told the owner that the only parts of value were the tubes. It would appear that said owner had dumped it in the skip having seen my friend, but after trousering the valves.

I'd say I'm 90% sure it's from a scope, and about 99% sure it's test gear, not an EMI Redd valve console (gutted!).

The skip was outside a house undergoing restoration. I reckon someone found it in the garden shed during said renovation. Maybe previous owner was a radio ham or similar.

Diabolical Artificer 6th Aug 2019 2:45 pm

Re: EMI Valve Scope Type B Amplifier - Free to a good home
 
Oh well, that would be Xmas X infinity finding an EMI/Redd/Pultec deck in a skip : )

I looked up EMI electronics, couldn't find much only that they were part of the big mega corp of which EMI music was also a part. Not sure about others here but I'd never seen or heard of an EMI scope or any test gear come to that.

Andy.

factory 6th Aug 2019 6:07 pm

Re: EMI Valve Scope Type B Amplifier - Free to a good home
 
If this is from an oscilloscope why does it have a control labelled "Meter Multiplier" and input & output connectors?

David

knobtwiddler 6th Aug 2019 6:52 pm

Re: EMI Valve Scope Type B Amplifier - Free to a good home
 
This is a good point. TBH I hadn't given it a lot of thought. I jumped to the conclusion it was something akin to a Tek scope plug-in from a similar era, particularly as the I/P is 1Meg.

It has sockets for a complement of 10 valves. The input on the front is labelled as 1M / 30pF. If it has 10 valves then maybe it does quite a bit of work, i.e. will drive a healthy voltage into a low-Z load. It's a small enclosure for 10 valves to be close together. I'd like to imagine that whatever it came out of gave it plenty of ventilation. It's quite lightweight and has no transformers.

It is in perfect condition btw. The rotary switch feels like it's hardly ever been used. There is no wear to the silkscreen or any other signs to suggest it's seen much use. It has a chunky gold-plated male connector on rear, a little like a German Tuchel. It's definitely a plug-in module of some sort. Could it be TV / RF-related?

I was thinking it could be used to make a small SE guitar amp or similar, but now I feel I ought to hold onto it and try and find someone who can use it for its intended purpose (I might be waiting a while, though :-)

A quick Google search reveals that EMI made a device called a 'scopemeter'. Here is a link: https://www.thevalvepage.com/testeq/...e/emiscope.htm

Scopemeter in above link only had 6 valves, though.

The 1M / 30pF input could reveal something, no? I started to wonder if it came out of a VTVM, but 10 valves in one module? A mainframe, incorporating a VTVM?

Trigon. 7th Aug 2019 10:10 am

Re: EMI Valve Scope Type B Amplifier - Free to a good home
 
3 Attachment(s)
I believe it's a plug-in from an EMI WM8 'measuring oscilloscope'.

Attachment 187973

I can't find a single photo of a WM8 on the web, but here's an earlier WM4:-

Attachment 187968

Note the panel meter. This enables more accurate measurements than could be achieved at the time using the screen graticule.

As the amplifier gain is switched, the range of the meter is effectively changed also - hence the switch markings.

The later WM16 replaces the meter with a calibrated shift dial:-

Attachment 187969

(From: https://sites.google.com/site/squirr...st-instruments)

Cheers

knobtwiddler 7th Aug 2019 11:47 am

Re: EMI Valve Scope Type B Amplifier - Free to a good home
 
Ladies and Gentlemen, I believe we have a winner!

Now all we need to do is find someone with a WM8 who has a use for this module!

I have to say that the construction quality is top notch. As you can see, there are no screw heads visible on the front panel. The whole thing appears to be made from alloy as it's very lightweight. To be honest, speaking as someone who works in specialist audio, 60 years down the line, I think there are a few OEMs around today who could learn from EMI's build quality! I kid not.

Bear2Biker 19th Aug 2019 12:43 pm

Re: EMI Valve Scope Type B Amplifier - Free to a good home
 
4 Attachment(s)
Just come across this thread whilst looking for info on the W.M.16 which I've recently aquired (No.119 in the collection) and needs some repair.

Yes the module is from a W.M.8 which I also have, you can see from the photo that it looks like this scope has a differential Y amp, so I wonder what the "Type A" amplifier offered?

I also have two TF1330's (well I thought I did) turns out the coverless one is a TF1331 which looks very similar but is the double beam version, I managed to clean up the #30 which had been in someones radio room for years & obtained a rather sticky nicotine veneer even inside as the fan filter had been removed.

The #31 arrived with no case panels and several siezed controls, it had probably been shed stored and got damp but I'm looking to get that working if anybody has info on it.

Diabolical Artificer 19th Aug 2019 3:24 pm

Re: EMI Valve Scope Type B Amplifier - Free to a good home
 
The first two pics of the scope look really like a Tektronix 500 series scope. The CRT bezel/cover is the same as is the construction in general. Does it have ceramic wafers inside or is it PCB based?

I have a few panels off an old Tek 545 that might fit, drop us a PM if interested. Apologies for hijacking the thread.

Andy.

factory 19th Aug 2019 7:24 pm

Re: EMI Valve Scope Type B Amplifier - Free to a good home
 
Quote:

Originally Posted by Bear2Biker (Post 1169603)
I also have two TF1330's (well I thought I did) turns out the coverless one is a TF1331 which looks very similar but is the double beam version, I managed to clean up the #30 which had been in someones radio room for years & obtained a rather sticky nicotine veneer even inside as the fan filter had been removed.

The #31 arrived with no case panels and several siezed controls, it had probably been shed stored and got damp but I'm looking to get that working if anybody has info on it.

If you looking for information on the last two scopes from your pictures, which are Marconi ones, it would probably be best to start a new thread.

David

knobtwiddler 22nd Nov 2019 1:35 pm

Re: EMI Valve Scope Type B Amplifier - Free to a good home
 
Just a quick note to say that I still have the module and it's free to someone who thinks they can do something useful with it.

B2B - it's yours if you need it!


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