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FERNSEH · 7th Oct 2019, 3:19 pm

Argus25 wrote: "I know what you are getting at and it is a difficult notion to modify a circuit to be far away from what it was as new because part of the charm of these old sets is their circuit quirks.
For the TV22 I would go for a compromise, just leave it there as it is but tack a resistor across the existing 100k and tack a resistor across the diode(it may not be necessary to disconnect the diode from its solder tags) to give the best sync pulse form at the grid and best interlace you can get with the existing capacitors and then what amounts to a 2 stage filter, then a purist could simply remove them one day to restore the original circuit."

The TV22 isn't a rare set so why not go ahead and improve it to a certain extent. Anyway, was that 100K resistor a mistake made not by the designer but perhaps someone in the components procurement department?

DFWB.

7th Oct 2019, 3:19 pm	#140
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Re: Bush TV22 with TC184 B3 converter. Argus25 wrote: "I know what you are getting at and it is a difficult notion to modify a circuit to be far away from what it was as new because part of the charm of these old sets is their circuit quirks. For the TV22 I would go for a compromise, just leave it there as it is but tack a resistor across the existing 100k and tack a resistor across the diode(it may not be necessary to disconnect the diode from its solder tags) to give the best sync pulse form at the grid and best interlace you can get with the existing capacitors and then what amounts to a 2 stage filter, then a purist could simply remove them one day to restore the original circuit." The TV22 isn't a rare set so why not go ahead and improve it to a certain extent. Anyway, was that 100K resistor a mistake made not by the designer but perhaps someone in the components procurement department? DFWB.