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weco: Circuit description

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Forum » Radios and other type of sets (Physics) etc. » MODELS DISPLAYED » weco: Circuit description
           
Georges Van Campenhout
 
 
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31.Jul.21 15:16
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Good afternoon,

I recently uploaded the self-drawn circuit diagram of this radio.

I am wondering how this set can operate with only one IF filter? What is the purpose of L9 in series with Ct3?

I think that this cheap radio was esigned to receive only the local transmitters?

 

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Tomasz Szczesniak
 
 
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31.Jul.21 15:35
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This is superheterodine receiver with regenerative detector on IF frequency. L9 and Ct3 are positive feedback elements, like in any regenerative radio. This principle of operation is rare, other radio build this method is Telefunken T4Z

This article was edited 31.Jul.21 15:36 by Tomasz Szczesniak .

Dietmar Rudolph
Dietmar Rudolph
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01.Aug.21 10:31
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Another example is Stassfurt Imperial 3W. This set has a penthode mixer and also a penthode regenerative detector with fixed regeneration. However, it has an intermediate frequency of approx. 470 kHz.

Regards,

Dietmar

 

Georges Van Campenhout
 
 
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01.Aug.21 14:05
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Thank you Mr.Szczesniak and Mr. Rudolph for your info. 

I wonder how to adjust the capacitor CT3? 

Unfortunately there is absolutely no information available for this radio.

Can anyone of you say something about the selectivity and the sensistivity of this kind of receiver?

Best regards

G.

Hans M. Knoll
Hans M. Knoll
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01.Aug.21 16:24
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If you look there  , special  on Titel,  is nearly th same quality.

mfg knoll  

This article was edited 01.Aug.21 16:39 by Hans M. Knoll .

Tomasz Szczesniak
 
 
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01.Aug.21 17:10
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Ct3 is for a reaction adjust. Its setting is related with both aelectivity and sensibility. It should be set to point where IF bandwidth is 9kHz. In practice - tune radio to some station and adjust Ct3 to loudest sound while the sound still has trebles.

  
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