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Old 2nd Oct 2019, 12:44 pm   #94
FERNSEH
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Join Date: Mar 2005
Location: Gateshead, Tyne and Wear, UK.
Posts: 7,444
Default Re: Bush TV22 with TC184 B3 converter.

Hi Peter,
The Masteradio frame sync separator is similar to the circuit used in the pre-war GEC BT9121.
There is a frame sync circuit in one of the 1950s Practical Television magazines which fully exploits the properties of the broad frame sync pulse train.
Without the circuit in front of me I can only guess that a resonant circuit is tuned to 20,250cps which allows only the frame sync pulses to pass through.
The waveforms show the frame sync pulses in almost total isolation from the line sync.
The only disadvantage of this circuit, if it is one, is that the frame sync separator will not operate on a simple single broad pulse.

DFWB.
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