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OK Maybe I wasn't clear.....
All thats required is to Duplicate the Drive Circuit from the Donor set, the components around the drive Transformer, and Drive Transistor any series or parallel caps and resistors, these may affect the drive transformer tuning, and the components between the drive Tx and the Horz-Out Transistor.
Goes without saying--ALL the components of the original Gate Drive circuit of the SG will need to be removed.
The Horiz Out Transistor in any conventional--And these Sony sets--(Or GTO, MOSFET, IGBT--Whatever),--
is used as a switch, and as such is driven hard on each time its needed,(Important) the timing derived by the horiz osc/sync circuit, at 15.625KHz in case of UK sets....
The Transistor Must be driven Hard On (Taken Care of by the Drive Tx and its Base components --or it will dissipate excessive power in form of heat and self-destruct....
Ive not ever seen any 'impedance issues' --a Transistor driven hard on has low V C-E anyway--just like its Sony GTO equivalent.
No apparent issues at all.
Providing a suitable Horiz Output Transistor is chosen that has a suitable Voltage and Current Rating, is Driven accordingly--Then it will work.
(There's NO reason you couldnt use an IGBT or MOSFET if its a 'Horiz-Out' type from a very recent donor set....
I see no real issues providing the Donor drive scheme is applied in each case)
All thats needed is to COPY the Design of the Drive Circuit from the Donor set--Schematics for both are needed for this. The last one I converted--was over 25 years ago, but clearly remember it being very easy!
The UK Publication will refer to donor parts from UK sets with specific values of components For those parts, as such would not be suitable for USA engineers, and also worth considering the differences in tuning for the different line frequency between UK and US format sets.....
Stick to Donor parts from what you have around in your country--Follow the drive schematic of the donor--you wont go far wrong!
Really IS a Junk-Parts conversion job, using scrap chassis parts.....
I used a variety of different donor set parts, from Philips G8 and Thorn drive transformers--Whatever I had around actually. I doubt there would be any of these donors around in the US!
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