nordmende: 258W (258 W); (Bremen)

Hello! I have one of these Nordmende that has installrd the optional FM module (UKW teil) with ECF12 tube.It is in almost working condition but covers only a 4 Mhz portion of the FM band, from 94 to 98 Mhz. I suspect that it could be normal for this model, due to the dial graduated from 0 to 100 instead of Mhz; but I don't know. It halso have a poor selectivity and I suspect that it is a superrigenerative unit, looking to schematic I seen that it is a classic AM radio without 10,7 Mhz FM if transformers. Unfortunately there is no this adapter schematic online. If you have any information or knowledge about it, please let me know!

Best regards to all, Enrico.

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Dear Enrico,

the FM-unit you have looking for is the Nordmende UKW E1, schematics can be found at the model page. You are right, it is a true super regenerative receiver with only one tuned circuit. Therefore, selectivity is limited to this circuit design.

But I think, the tuning variation should be at least go from 86...100 MHz. About 4 MHz is much too less. Maybe there is something wrong with the inductive tuned circuit (Variometer). Please check the mechanical travel of the (feritte core?) which moves inside of the oscillator coil (only visible when the unit has been opened..). Perhaps a mechanical adjustment will fix this problem. Some pictures with the model page shows the interior of the UKW E1.

Bernhard Nagel

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I suppose the UKW superregenerative module might be the UKW E1 from Nordmende.

Regards, Dietmar

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