Good evening,
I was just studying the schmatic of a GE-501 AM Tube radio. The material I have says that there is 4 different frequencies at the plate of the 12SA7 converter tube.
The station frequency, the LO frequency, the addition and the difference of these signals. If I use a frequency counter can I read the values of these frequencies?
Any ideas????
Thank you kindly!!!
Daniel

Here is a link about the converter stage. This may help understand the fore Frequency’s.

http://www.radioremembered.org/convtr.htm

Daniel

The simple answer is no. Connected to plate of the converter tube will be an IF Transformer. This IF Transformer eliminates the original signal, oscillator and sum of the frequencies.

Only thing left is the difference between received signal and oscillator. Signal level will be low but you could read it on a frequency counter. Usually 455 to 465 KHz, depending on IF Frequency of the radio.

Norm

:Good evening,
:I was just studying the schmatic of a GE-501 AM Tube radio. The material I have says that there is 4 different frequencies at the plate of the 12SA7 converter tube.
:The station frequency, the LO frequency, the addition and the difference of these signals. If I use a frequency counter can I read the values of these frequencies?
:Any ideas????
:Thank you kindly!!!
:Daniel
:

:Daniel
:
: The simple answer is no. Connected to plate of the converter tube will be an IF Transformer. This IF Transformer eliminates the original signal, oscillator and sum of the frequencies.
:
: Only thing left is the difference between received signal and oscillator. Signal level will be low but you could read it on a frequency counter. Usually 455 to 465 KHz, depending on IF Frequency of the radio.
:
:Norm
:
:
:
::Good evening,
::I was just studying the schmatic of a GE-501 AM Tube radio. The material I have says that there is 4 different frequencies at the plate of the 12SA7 converter tube.
::The station frequency, the LO frequency, the addition and the difference of these signals. If I use a frequency counter can I read the values of these frequencies?
::Any ideas????
::Thank you kindly!!!
::Daniel

Another thing, you have not filtered the input to the converter tube very much, there will be other frequencies from other radio stations as well. This is what the IF amplifier does, reject everything coming out of the converter except 455 kHz. You are reading pure theory, the actual fact is a little different.
Lewis
Lewis
:
: