Vintage Audio Activities...

[CitroJim]

The lovely thing about the European valve coding is you can readily identify exactly what it is from its code. An EBF83 for instance being a double diode and signal pentode with a 6.3V 300mA heater.

To the uninitiated that appears to have no logical use of letters and numbers to translate EBF83 into double diode and signal pentode with a 6.3V 300mA heater. I presume it just does

Maybe its like the Chinese takeaway system where 81 translates into Sweet and Sour Chicken with fried rice

Neil

There is a very comprehensive table available that allows the full decoding of all European valves Neil. Which is why I said I could go on... If you are interested I could dig it out. We who have been around them for a lifetime just know it...

Briefly:

First letter - heater voltage. E being 6.3V, U being 100mA series and so on.
Subsequent Letters - type. A - single diode, B - double diode, C - signal triode, D - power triode, F - signal pentode, H - hexode, L - power pentode, Y - power rectifier diode. The number of subsequent letters after the first (heater) letter tells how many individual valves are in the same envelope. E.g. ECC83 is two triodes in the same envelope. An EL84 is one power pentode. An EABC80 has four - work it out

The first number after the letters indicates the base/envelope type. 8 is B9A Noval 9 pin, 3 is International Octal and 9 is B7G, a miniature 7 pin base.

The last number(s) uniquely identify the valve.

That's just a taster of the most common types. There are thousands more!

All the above from memory...

[NewcastleFalcon]

Thanks Jim for the explanation. Yes a good old code book required to attribute meaning to letters and numbers, until you learn to read and speak the language. No plans to become fluent myself but I will always ask the question if something sparks my curiosity.

Neil

[CitroJim]

Thanks Jim for the explanation.

A pleasure Neil And pleased you found it of interest...

As this was about hybrid car radios, early transistors followed the old valve code for a while before they received their own - which I also know off by heart still...

Early transistors invariably are OCxx where O means no heater and C, a triode. the following numbers uniquely identified the device... The OC71 was possibly the most ubiquitous early transistor of all time...

[Peter.N.]

You forgot tuning indicators- EM and shunt EHT shunt stabilisers PD Jim They were the ones used in the Bush CTV 25 the load of which caused the LOPT to burst into flames.

Peter

[Peter.N.]

That won't be the one Neil it was a valve set.

Peter

[CitroJim]

You forgot tuning indicators- EM and shunt EHT shunt stabilisers PD Jim They were the ones used in the Bush CTV 25 the load of which caused the LOPT to burst into flames.

Peter

The EM series - also known as 'magic eyes'

I also forgot Z (full-wave rectifier) as well Peter! I well remember the PD500 and GY501 combination to generate the stabilised 25Kv EHT in early colour sets Such happy days! Used to love working on those monsters

[Paul-R]

... the stabilised 25Kv EHT in early colour sets Such happy days! Used to love working on those monsters

And by extension, working with x-rays!

[CitroJim]

... the stabilised 25Kv EHT in early colour sets Such happy days! Used to love working on those monsters

And by extension, working with x-rays!

Indeed, the enclosure containing The EHT rectifier and shunt stabiliser valves was interlocked to prevent operation with the shielding removed...

The valves themselves had warnings printed on them...

Lots of debate over the years just how much of a risk existed. We always felt it was never worth taking the chance to find out!

[Peter.N.]

Yes, they're the ones Jim. There was always speculation about X-rays in fact the opinion was that there was more emission from the gun end of the tube but I sat very close the the gun end at my bench for about 50 years and I'm 85 now! We also used copious quantities of carbon tetrachloride and tin-lead solder as well as asbestos dust from brake and clutch linings also inhaled much cellulose paint spray in my time but I'm still here.

I know I am fortunate because I have had friends die from asbestosis, I wonder why it affects some people and not others - there's still time of course.

Peter

[Stickyfinger]

There was always speculation about X-rays in fact the opinion was that there was more emission from the gun end of the tube but I sat very close the the gun end at my bench for about 50 years and I'm 85 now!

Says the Invisible man

[CitroJim]

There was always speculation about X-rays in fact the opinion was that there was more emission from the gun end of the tube but I sat very close the the gun end at my bench for about 50 years and I'm 85 now!

Says the Invisible man

We also used copious quantities of carbon tetrachloride and tin-lead solder as well as asbestos dust from brake and clutch linings also inhaled much cellulose paint spray in my time but I'm still here.

I know I am fortunate because I have had friends die from asbestosis, I wonder why it affects some people and not others - there's still time of course.

Peter

Same here Peter, plus I spent many years working in high RF fields. Most of what we used on a daily basis has long since been banned. It's bloody remarkable I'm in as good physical health as I am... Mental health is another matter entirely...

As you say, there's still time and as an ex-smoker I fully expect to fall victim to it in the next few years...

Hence I'm living the fullest possible life now whilst I still can...

[Peter.N.]

Don't blame you Jim.

Peter

[CitroJim]

Just seen this on the Vintage Radio forum Neil and I immediately thought of you and this thread

A Falcon Stereophonic Radiogram...

Borrowed from the UKVRRR forum

A new one on me I must admit...

[Peter.N.]

There are quite a few on Facebook market place. Some even at reasonable prices!

Peter

[NewcastleFalcon]

Just seen this on the Vintage Radio forum Neil and I immediately thought of you and this thread

A Falcon Stereophonic Radiogram...



A new one on me I must admit...

Jim....Are you familiar with Dazzlevision on the UK Vintage Radio Repair and Restoration forum

This post from that member has a bit of info on "Falcon" Radiograms

The radiogram you show pictured was probably manufactured by John Street Manufacturers Ltd, 88 Springbank Road, London, SE13 (in 1955). In business since at least 1950. In 1953, at 117 Manor Lane, Lee, London, SE12. In 1958, they relocated to Falcon Works, 71-73 Beacon Road, Lewisham, London, SE13. Maker of “Falcon” radiograms. Still going in 1964 & 66.

They were a minor brand name and will be pretty uncommon, I expect. We had a discarded "Falcon" radiogram at work for years, although it was a 1960s transistorised unit.

Neil