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#133609 - 08/30/02 10:50 AM Old radios
pauluk Offline
Member

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
Regulars will know that a lot of my time is spent working on electronics, and I like to pick up old radio equipment to refurbish.

By way of something different, I thought I'd post some pics of my latest project. This is a mid-1950's tabletop Regentone radio & phonograph, or "radiogram" as they were called in England at the time.


This one is somewhat unusual in that the record deck hides behind the flip-down tuning scale:


For the radio enthusiasts among you, the chassis is a fairly conventional 5-tube line-up: ECH42 (converter), EAF42 (I.F.), EBC41 (detector & 1st audio), EL41 (audio output) plus EZ40 (rectifier). (They're called "valves" over here, by the way!)


The tuner section is 3-band, conventional MW broadcast, SW (6 - 18MHz), and LW (150-300kHz) which is also a broadcast allocation in this part of the world. The turntable is one of the early BSR Monarch 3-speed changers.

This one came from a local auction; it needs some work, but at least it's in good shape and complete, and it looks as though it's been stored in a dry place.


[This message has been edited by pauluk (edited 08-30-2002).]

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#133610 - 08/30/02 12:06 PM Re: Old radios
Bjarney Offline
Moderator

Registered: 04/10/02
Posts: 2561
Loc: West-Southern Inner-Northeast ...
Paul, a long shot — is that the [3rd pic, 2-deck maybe?] tuning capacitor left side above the chassis? Is it mechanically connected to the flipdown scale? …with that woven ‘fishline’ string?

Quite a find. {A lot of people never understand.}




[This message has been edited by Bjarney (edited 08-30-2002).]

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#133611 - 08/30/02 12:12 PM Re: Old radios
HotLine1 Offline

Member

Registered: 04/03/02
Posts: 6804
Loc: Brick, NJ USA
Paul:
Nice cabinet and a nice radio.
Just dropped in to see what's happening outside of the US
HotLine1
John

Have a good weekend, & "Labor Day" Monday, if you guys have it as a holiday.
_________________________
John

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#133612 - 08/30/02 12:20 PM Re: Old radios
Texas_Ranger Offline
Member

Registered: 12/17/01
Posts: 2343
Loc: Vienna, Austria
Just one minute after reading your post I found something in my room that's related to this post.
I found a box with 5 valves, all "Made in England". 3 Mazda ones (ECC83, ECL82, EL84) and 2 Brimar (EZ 80 and something that looks like EM84, the labeling is very hard to read).
They come from a reel tape recorder I took apart years ago. It was a strange thing, made by a company called "Modern Techniques, England), wooden case covered with red Plastic. I'm curious about that. Have you ever heard of this Company? Are those common in England?
I'd love to get one.

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#133613 - 08/30/02 02:15 PM Re: Old radios
pauluk Offline
Member

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
BJ,
Yes, that's the multi-gang tuning capacitor/condenser fitted with the usual large pulley on its spindle around which is wound the dial cord. This model is fairly intricate in that department due to the flipdown lid. The tuning knob is located on the right-hand side of the cabinet (as viewed from the front).

John,
Nope, no holiday on Monday here. We had a "bank holiday" a couple of weeks ago. (You can tell it was a holiday -- It rained!)

Tex,
The plastic covered wooden cases were very popular here on radio equipment in the 1960s. One trade name was "Rexine." The best way I can describe it is that it's a sort of plasticized textile covering. Some old radios, tape recorders, etc. turn up on e-Bay from time to time, although in varying conditions.

I'm not familiar with the Modern Techniques name; I've had a quick look at some of my old reference books just in case, but I can't find anything listed under that name. My guess would be that it was a small independent manufacturer, possibly even just using somebody else's chassis.

The valve line-up you listed was a very common one for British tape recorders of the era. The ECC83 is an audio amplifier, the ECL82 and EL84 were used as audio output and bias oscillator (for recording) in various combinations. Some models used only one of these. The EZ80 is the rectifier.

The EM84 is a cathode-ray display, commonly called a "magic eye" indicator. These were used as tuning indicators on some radios and as level indicators on many domestic tape recorders. Some types were round displays, but the EM84 is just a small horizontal bar. If you look closely you'll see the section which would have been placed so that it was visible through the panel. Love that green glow!

A name I'm sure you'll be familiar with is Telefunken. I was given one of these old tape machines when I was a kid in the 1970s. It weighed a ton (or so it seemed to me at the time), but I spent many happy hours cleaning it up and using it.

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#133614 - 08/30/02 11:37 PM Re: Old radios
Trumpy Offline

Member

Registered: 07/05/02
Posts: 8540
Loc: SI,New Zealand
Paul,
I have a large box of valves at home,
here, there are various types and
3 of them are the "Magic-Eye", it is like
a big green neon,not sure what voltage,
(filament,anode,etc) they work on, can
anyone tell me?
What I do know, is that they came out of
various Reel to Reel tape recorders,
that I fixed in the very early years of
my life as a trainee technician, bits
like this scare me, as it shows my true age.
But if anyone is looking for an odd valve
(tube), let me know, chances are I have it.
_________________________
Let's face it, these days if you're not young, you're old - Red Green grin

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#133615 - 08/31/02 05:13 AM Re: Old radios
pauluk Offline
Member

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
They're actually a miniature cathode-ray tube rather than neon, and work in much the same way as a TV or oscilloscope tube, on a more simplified basis.

Another common use was as a null or balance indicator. I have one used as such in an old resistance/capacitance bridge.

Operating voltages are pretty much the same as for the other valves they were used with, generally anything from about 150V upward on the anode (plate), although some will operate right down to 90V or so. The same goes for the other valves, generally 150 to 300V for mains types, but the valves designed for battery portables were made to run on a 90V HT battery. (I'm speaking of domestic radios here; TV sweep stages, high-power transmitting valves, etc. could run into the kilovolt range.)

Filament voltages in the 1950s/1960s era are most often 5, 6.3 and 12.6 volts, although others were used, mainly on power tetrodes/pentodes and C.R. tubes. (5V filaments were most common in rectifiers.)

In the British/European valve coding of that time, the first letter indicates the filament characteristics. The "E" in all the above examples means 6.3 volts. The American tube coding also uses the first number to give the filament voltage, e.g. 6SN7 is a 6.3V filament, 5V4 is a 5V type.

There are a few anomolies, e.g. the ECC83 actually has a center-tapped filament which can be wired parallel for 6.3V or series for 12.6V. It is a direct equivalent of the American 12AX7.

By the way, Tex mentioned the Brimar name. The name originated as a contraction of BRItish Made American Range, as the company was set up originally to manufacture American specification tubes here.


[This message has been edited by pauluk (edited 08-31-2002).]

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#133616 - 08/31/02 05:48 AM Re: Old radios
George Corron Offline
Member

Registered: 05/16/01
Posts: 728
Loc: Lorton, Va USA
Paul,
Good find. At our hamfests here Zenith transatlantics have been popping up a lot, very similar (without the turntable though), a lot of my friends have rebuilding/restoring old radios as a hobby. Over my head right now I have a Collins 51J receiver. It, fortunately, does not need restoring and is in beautiful condition and still works very well.

The big problem with it is that it is just a receiver, and it only can tune within the ham bands. I do listen to shortwave and commercial radio a good bit, but I use either my Ten-Tec Jupiter, or my Kenwood TS 570, they are both extended coverage. In the bands it can tune, the Collins puts out the rich old sound I know you are familiar with, of course all filters are mechanical.

Sorry to hear you don't have labor day on the other side of the pond........slow down and think about us, I'll hoist a burger for you.


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#133617 - 08/31/02 10:48 AM Re: Old radios
Bjarney Offline
Moderator

Registered: 04/10/02
Posts: 2561
Loc: West-Southern Inner-Northeast ...
Paul— Off topic slightly, but one memory has surfaced. A couple of decades ago, I worked on an accelerator that used a lot of custom English Electric Valve thyratrons. One day I was talking with a power-supply designer on the project, {he was almost stupefied that anyone would have an interest in what he did} and got to discussing specs that only EEV could meet, and partway through his fond recounting, his eyballs glazed over describing the trip he took to visit the factory. I remember well his comment, "Now, those folks know how to entertain visitors." His knees seemed to almost buckle at his recollection of the tour. I won't forget that conversation.

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#133618 - 09/01/02 03:59 AM Re: Old radios
Texas_Ranger Offline
Member

Registered: 12/17/01
Posts: 2343
Loc: Vienna, Austria
Thanks for the explanationb of all the valves!
I took that machine apart when I was about 7 years old and this is the only thing I kept (except for the name plate and the power cord, very very thin wires, nearly looked like low Voltage, old British color coding, no plug attached, wires just ripped off)
These cases were pretty common here also, but this one was such a particularly awful red I've never seen before or after. Top was some kind of grey-green wirecloth , the control bar beige plastic. I guess the machine must have been rather hogh-class as it was a 3 motor direct drive setup (all other machines I've seen were 1 motor belt driven),3 speed (4.75, 9.5 and 19 cmps), built to be used vertically as the reels could be secured with screws.
I really regret having taken it apart as I'll probably never get anything like that. Probably it would even have worked if I hadn't mistaken the green wire for the phase and the red one for the ground.
Sure I know Telefunken, but it has never been really common in Austria. Phillips, Grundig and Hornyphon (Austrian Philips license) were most common here, along with Revox in the high-end section. I collect those things but pitifully never managed to get one with a magic eye instead of the common magic band.
One of the nicest things in my collection is a portable Telefunken 302 (battery powered, reels up to 13 cm)

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