Telefunken Italia - model "Mignonette MF" - 1a Serie
JAN 2023 - restoration notes.
I don't want to bore you with information that is already available on the net about radio restorations and/or about this particular radio model.
I just want to share my restoration notes and annotated schematic.
This radio has the chassis directly connected to the power line.
There is a very HIGH risk of electrocution - use an isolation transformer when working with this kind of old radios.
Please note the use of an auto-transformer that imply no isolation from mains (!!) and as the power switch is directly connected to the power line. There is no fuse!
Everyone putting his hands into this chassis must know what he is doing!!
I started replacing all paper caps and the 3 electrolytics.
Then I replaced all the resistors that measured way out of specs. Some of them are unreachable (left alone).
This Italian radio makes use of one of the first attempts to integrate components on a single "chip": they are LARES boards.
Here are few examples:
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| Excerpt from LARES manual |
Here are the ones I've replaced.
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| The units replaced |
While it looked a good idea at that time to introduce simplification to the spaghetti layout approach of the time, it turned to a nightmare as time goes.
As many other noted on the net, they shift way out of specs with time and mine are not exception. I replaced them all with discrete components.
The radio is working now: FM is really OK; on other bands it remains heavily deaf.
It probably needs a complete IF alignment but I have no time left and I do not want to risk breaking the coil slugs (they are strongly glued and look very fragile).
Here is my annotated schematic diagram for you guys to enjoy.
LARES modules (NOR-323 and NOR-322) are highlighted.
Hope this help.
Ciao, Emanuele.
User manual:
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