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Trying to resurrect a volksempfanger. It came in messed up pretty bad: busted slide rule dial (paper dial sandwiched between two pieces of heavy plate glass), output transformer ripped off the speaker and all the wires torn loose from the transformer, and, last but not least, one busted tube. Didn't even SEE that it was busted until I really dug into it, I thought it was just the oddball cap being loose. [Image: https://www.facebook.com/images/emoji.ph.../1f641.png]:(
Now, here's where I hope somebody can point me in the proper direction.. the broken tube is listed on the schematic as an AF7, but the tube in the set says Telefunken 48, which I can't even find a listing for. Can someone advise me if these are equivalent tubes?
(This post was last modified: 12-07-2016, 08:34 AM by
BrendaAnnD.)
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Radio museum with their German background could have some info.
Also ask on Peter's forum - they deal with VEFs (not sure why you called it Volkempfaenger, it is Latvian, Latvia became a Soviet territory in 1940 I think).
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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Mike,
Because that's what they call it. Several different cabinets with the same chassis, all called volksempfangers. Think this one was made in Bavaria. I've got two others coming as well, same circuit, different manufacturers, all part of the German propaganda system. Perhaps what you're thinking about is a Latvian brand name, rather than these?
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I see the problem... that "F" doesn't belong there, so I got the "F" out of there..
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Aha....yep. VEF was Latvian photo and radio manufacturer, pretty famous too.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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I remember running into a website about Volksemfanger sets a while back, I even bookmarked a page about them either posted by someone in Germany or Austria. If I remember correctly they all seemed to use a three tube regenerative circuit, but I don't recall whether they all had a power transformer or whether some were series string. AF7 sounds like it would be the proper type from what I could find about most other VR301s. Unfortunately the Germans, like the British, seemed to have this silly predisposition to using 4 volt filaments in many of their tubes, which seems to lack any rhyme or reason. It looks like its an expensive tube too if fleabay BIN prices are to be believed , I wonder if the 6.3 volt EF7 is cheaper. Basically it's an RF amplifier pentode of some kind, at least with this you can work out a substitute if there is one. Maybe you can make an adapter out of it's base and use a cheap and useless series string TV tube like a 4BA6?
http://tubedata.tubes.se/sheets/030/a/AF7.pdf
Regards
Arran
(This post was last modified: 12-10-2016, 04:17 AM by
Arran.)