NB: This thread and the thread: The Swedish model Norwegian design http://tinyurl.com/mv73z2r (http://tinyurl.com/mv73z2r)
are related.
This bakelite telephone are best known as the "Swedish model"
Designed by the Norwegians: Christian Bjerknes (idea 1930) and Jean Heiberg (artist)
Its made with lots of diagrams, in Norway 4 diagrams (in CB versions) was used:
One for use on PAX's etc One for the Telegraverket departments in each cities of:
Trondheim, Stavanger and Bergen.
dsk
If we compare the circuit of the Trondheim version with a W.E. 302, it is quite similar.
The hook switches has changed plase in the circuit, and the capacitor is slightly different. The capacitor in circle A could be removed without problems, and the hook-switch in circle B could be replaced of a strap without problems.
The EB telephone uses the same capacitor for ringer and anti side tone circuit. The 302 has more compact modern capacitors and was able to put in 2 capacitors in the housing. (The ringer are also more modern in the 302.)
dsk
This dial are from one of these, and stamped: A-S Elektrisk Bureau Oslo.
It is pretty unstable, it may be because of its old and not served. It is definitely different from all others I have seen.
dsk
(http://www.classicrotaryphones.com/forum/index.php?action=dlattach;topic=8891.0;attach=113101;image)
I have the exact same dial. Only it is stamped Telefon A.B.L.M. Ericsson, Stockholm and a serial number: 275652
I cleaned and polished it quite a while ago, but have not tested it. I'll be interesting to put it to my analyser.
That last pic of the desk phone you posted, it seems to have an version of the E4 handset. Is that original?
The one with the metal dial are for sure the right one to the phone. The one with the bakelite dial has a handset more common on the 1934 versions of magneto, and Oslo telephones. I,m not sure if this has been used from start of this telephone, but I was surprised when I got it. Later I have seen more of these.
dsk
A new scan of schematics with new part no, still pretty equal:
dsk
These phones has no bias spring, and tinkles. My solution:
dsk