Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition
 

Agreed that is the logical interpretation here. I was unaware of that meaning before now, but I had previously seen “secteur” as a short form of “secteur industriel”.

For most purposes the EAA91, EB91 and 6AL5 (and the D77 and 6D2) seem to have been viewed as being interchangeable, despite their physical differences. Perhaps there were some subtleties that required both the EAA91 and EB91 versions. Maybe the EB91 was too tall to fit some compact equipment that had been designed around the 6AL5, so an exact physical copy of the latter was required in the European series, hence the EAA91. It would appear that the EB91 preceded the EAA91. The EB91 followed the EB41, but then the design of the latter may have been influenced by the 6AL5. There might be a complex story in there that has yet to surface.


Cheers,

Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition
 

Without formal data, one might (tenuously) infer that using B as the designation for "double diode" signifies that they were identical types designed to match closely in characteristics (e.g. for something that explicitly needed two matched diodes, such as a discriminator or other balanced use), whereas the separated AA might suggest two diodes that were not necessarily identical in characteristic, but that were perhaps more thoroughly screened from each other.

Straying a little from the original thread title, though.

Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition
 

From a preliminary look, I'd ay that the miniature double diode issue warrants a separate thread, so I'll plan on starting one soon.


Cheers,

Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition
 

The double diode thread, "Why Both EAA91 and EB91", has been started at: https://www.vintage-radio.net/forum/...06#post1183106.


Cheers,

Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition
 

Some sense of Philips’ general transition from Rimlock to noval types may be gleaned from the Preferred Types tabulations from a couple of Philips valve pocket books.

The first of these is Philips Electronenbuizen Zakboekje of 1953.

Attachment 191875

At this time, in the 6.3-volt and 100 mA heater groups, the preferred valve positions were about equally shared between Rimlock (yellow highlighting) and noval (green highlighting) types.

The second is a 1954 Pocket Book.

Attachment 191876

By this time novals have displaced Rimlocks as preferred types in all but one case, namely the EL42 car radio output valve. This was replaced by the noval EL85 c.1955.

Some of the Australian Innovals appear never to have been released outside of Australia, as noted below.

6AD8 (EBF81) Australia only
6AN7 (ECH80) Australia only
6BH5 (EF81) Australia only
6BD7 (EBC81) Not released in Europe until c.1954, displacing the EBC41
6M5 (EL80) Australia only
6N8 (EBF80) Released in Europe at about the same time as in Australia
6V8 (EZ80) Not released in Europe until c.1953, displacing the EZ40.


Cheers,

Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition
 

I do thank Synchrodyne for that input!!

I know intimately every valve by its Australian number. To FIND a data book with all the cross references was and remains a REAL pain. Most databooks even the Philips/Mullard books didn't list valves that way. It was required to go to the back "short" section, FIND the equivalent, then reopen at the listed alternative and go from there. I thank god for American logic in this case.

It's just my take after 55 years, AT LEAST, of looking up alternatives.

Joe

Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition
 

In Europe we have the opposite problem, as we know that the American valve names are virtually meaningless. Is a 6360 a QQV03/10 or a QQV03/20? Few American databooks even mention the European names.

Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition
 

Thus far I have not found any evidence that the Philips Australia Innoval valves were used in New Zealand radio receiver production.

That comment derives mostly from a selective look at the radio receivers detailed at this site: https://www.vintageradio.co.nz/.

During the 1950s, the NZ radio makers made extensive use of Rimlocks and the later noval series - with their primary Pro-Electron designations, including mixed lines-up, as well as American valve types.

That is not to say that cases where say one or some of the EF81 (6BH5), ECH80 (6AN7), EL80 (6M5), EBF81 (6AD8) were used will not be found with a more extensive search.

The EBF80 (6AN7) was used in NZ quite early on, but this was released in Europe at the same time as in Australia.

NZ use of the EBC81 (6BD7) and EZ80 (6V8) appears not to have been before those two were released in Europe.

So mostly at least, NZ followed European practice when it came to the Rimlocks and European novals.

Nonetheless, there was some Australian influence in NZ practice in that the 6AE8 was found in otherwise American lines-up. 6AE8 was the AWV designation for the Osram X79, which infilled what was a significant a gap in the American range, at least for setmakers who followed European precepts when it came to AM frequency changers.


Cheers,