Help to Identify Marconi 3 valve set "EtherPlus"

[NickG0HIK]

My father turned up with this empty case the other day that he picked up at a village sale and thought I might use it.
Well it will probably go on to the pile of "Sometime in the future jobs". I thought it might be fun to build something sort of original in it, if I have or come across suitable knobs etc.

A Google search has not been fruitful yet.

Its a Marconi Three valved set, labelled as an "Etherplus". A picture of one and a circuit would be great if anyone has any information?

Thanks

Nick G0HIK

[Paul_RK]

I expect the only Marconi connection is a license plate ("Royalty has been paid on this apparatus...", or whatever the wording was). Trademarks were zealously guarded and Etherplus existed as a brand for valve holders, potentiometers, etc., so my guess would be that the company responsible for those decided to try marketing a few complete receivers, or perhaps kits. That would make it quite a scarce, possibly a unique, box, but the downside is that even a photo of the complete set would be a very fortunate find.

I'm not sure where my little collection of Broadcaster trade annuals is: those carried comprehensive lists of trademarks, who owned them and the categories of item they were used for. I think my earliest is from 1933, which could be too late for the enterprise behind the Etherplus brand, but if not it would at least provide the name and address of the manufacturer.

Paul

[Ed_Dinning]

Hi Nick, it would be useful to be able to reconstruct it as original, but most 3 valve circuits were pretty generic.
I would suggest some research on the "Etherplus" or similar components as a starting point

Ed

[AdrianH]

Doing a quick search on the wireless history web site Etherplus valve holders were made by M and A Wolfe of 9 to 15, Whitecross Street, London E.C.1.

Adrian

[Catkins]

Originally Posted by AdrianH

Doing a quick search on the wireless history web site Etherplus valve holders were made by M and A Wolfe of 9 to 15, Whitecross Street, London E.C.1.

Adrian

Which became "MANDAW Co Ltd" by about 1930.

https://www.gracesguide.co.uk/Mandaw_Co

Which dates it to the mid to late 20s, which is completely consistent with the style of box.

A look through the online literature of the time shows they were also making inter-stage transformers

https://worldradiohistory.com/UK/Pop...2-12-S-OCR.pdf

and variable capacitors

https://worldradiohistory.com/UK/Wir...5-12-S-OCR.pdf

as well as valve holders. So it is entirely possible they branched into kits or complete radios.

[NickG0HIK]

Many thanks all for the responses.

So it is likely to have been a kit or made to a published design and the box was supplied by Mandaw.

I don't understand the terms of the Licencing Plate, does that mean it was built to a design from Marconi ?

The back of the front panel has a label which looks to be original and appears to say "106" on it, a part number? I don't think its 10'6.

The box is in good condition and no sign of worm, so I do think its worth a future project.

Although this isn't really my sort of thing, I do have some parts from this era and I'll print out the other Etherplus parts from the adverts and see what I can get together to build something of the period.

[Paul_RK]

The licence plate appeared on just about every manufactured radio and referred to a royalty payment made to the Marconi company in order to make use of the basic patents for radio reception - the patent holders just sat back and gathered in the royalties, it doesn't suggest any design input. I'm not sure, but I've a feeling the plate wasn't used on home constructor sets - someone may be able to confirm this one way or the other - which would point to the radio being marketed as a complete and finished item by M. and A. Wolfe.

Can't be definite about the paper label, but one distinct possibility is its being a serial number for the set. Often in this period the serial number would be engraved on the front panel along with manufacturer details and legends for the controls, but clearly that's not the case here. If it is the serial number it doesn't necessarily mean that 105 radios were made before this one, they may for example have decided to start at 101 to suggest a larger scale than the operation actually had.

Paul

[NickG0HIK]

Thanks Paul,

All most helpful.
Of course I'll post on here as and when I get on with the project. But the learning process from the research is just as important and enjoyable as the actual repairing and construction.


Thanks

Nick G0HIK

[Paul_RK]

Not a great surprise, but now that my little stash of Broadcaster Trade Annuals has turned up I was able to consult the earliest of them, 1933, for Etherplus as trademark, M. & A. Wolff, Mandaw, and... nothing. Doesn't of course necessarily mean the company wasn't still a going concern, just that it had very probably ceased all activity in the radio field by then.

[Catkins]

Originally Posted by Paul_RK

The licence plate appeared on just about every manufactured radio and referred to a royalty payment made to the Marconi company in order to make use of the basic patents for radio reception - the patent holders just sat back and gathered in the royalties, it doesn't suggest any design input. I'm not sure, but I've a feeling the plate wasn't used on home constructor sets - someone may be able to confirm this one way or the other - which would point to the radio being marketed as a complete and finished item by M. and A. Wolfe.

I have checked up on this in "Radio! Radio!", which has a fair amount of details on the royalty payments and changes to the licence.

The short answer is the royalty payment (and hence licence) was only due on complete receivers manufactured by a company, and not on kits or home constructor sets.

The changes in the licence are quite interesting, and worth describing.

January 1923, large increases in purchase price of valve receivers due to introduction of Marconi A1 and A2 patent royalty licences. A member of the "Big Six" companies had to pay an A2 licence, where 7/6 (7s 6d) was charged per valve holder. All other companies had to pay an A1 licence, where 12/6 (12s 6d) was charged per valve holder.

During 1928, the Brownie Wireless company began a legal fight challenging the validity of the Marconi patents under which the licence was required. Brownie was granted a compulsory licence to manufacture valve sets at a lower royalty cost. But Marconi appealed the decision.

June 1929 Marconi successfully won their appeal, leaving the fixing of Marconi royalties in Marconi's hands.

Shortly afterwards negotiations entered between the company and the RMA (Radio Manufacturers Association) to determine the future situation.

Negotiations ended in November 1929, and a "three-power pact" was announced between Marconi's, The Gramophone company and Standard Telephones which enabled a single combined manufacturing licence to be issued. Known as the A3 licence it came into effect in November 1930, with a reduced charge of 5 shilling per valve holder.

Given the above information I wondered if it might be possible to more precisely date the EtherPlus+ box based on the style and text of the licence plate.

I therefore had a look at the licence information present on a number of radios in my collection from 1924 - 1933.

Radios from 1924 - 1927 tend to only have brief licencing text and it is ad-hoc without any standardised form between manufacturers. Photo 1 is the typical licence information from a Sterling "Anodion" radio of 1924.

Photo 2 is from a Pye radio from 1929, it is now very similar in style and text to that of the EtherPlus+ licence plate.

Photo 3 is the licence plate from a 1931 Lotus Bud 2. This differs in that it has a serial number, and it is now a combined licence mentioning Marconi's, the Gramophone Co and STC.

Photo 4 is a later plate from 1933, showing the Gramophone Co has been replaced with EMI, which was formed from the merger of the Gramophone Co and Columbia on 31st March 1931.

So for what is worth, the set was a complete and finished item, and must have been manufactured before November 1930, because it is using the original A1 licence. But, from the style it is unlikely to have been made before 1929.

[PJC58-Hythe]

If you want to see some typical circuits of the time (and some other interesting stuff) go here https://worldradiohistory.com/UK/Wir...6-11-S-OCR.pdf