I'm repairing this amp and the psu driver transistors are blown the original instaled was a1266,(the service manual saids a1268 for the PSU driver transistors) what do you think about replace this with a1023?..... I have in hand a1023 , if this is not a good idea i could order a1266.
I asked about this because i have repaired another class d amps and some of them use in their psu a1023 transistors as transistor drivers.
Thank you
I asked about this because i have repaired another class d amps and some of them use in their psu a1023 transistors as transistor drivers.
Thank you
Thank you caraudioguy, the topology is a bit diferent this Psu uses only pnp transistors in the Psu use the 494 Ic instead 3525 Ic.
I think a can try installing it and monitor the signal performance current and temp
I think a can try installing it and monitor the signal performance current and temp
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Thank you Perri, i already have the service manual.
Perri, What do you think? could i replace the blown a1266 with a1023? or is better to order the exact transistor?
Perri, What do you think? could i replace the blown a1266 with a1023? or is better to order the exact transistor?
The manual was to allow those not familiar with the circuit to see what it was.
If you don't have access to the 1023 new, I'd save them for applications where you need the high speed and high voltage of the 1023. If you have access to them (new), use them.
If you don't have access to the 1023 new, I'd save them for applications where you need the high speed and high voltage of the 1023. If you have access to them (new), use them.
I have a couple of a1023 maybe i should keep them for another aplication, i have 10 a1220 i have use a 1220 instead of a1023 and the amp is working fine.
But i do not know if i cand replace a1220 instead a1266,
If i use a1220, Will this transistor be overcharging the 494 ic???
But i do not know if i cand replace a1220 instead a1266,
If i use a1220, Will this transistor be overcharging the 494 ic???
I don't understand the 'overcharging' term.
Are you referring to the KSA1220?
Those are OK as drivers.
For generic PS drivers (to keep in stock), I'd suggest the BD139 and BD140. They're good subs and readily available (here, anyway).
Are you referring to the KSA1220?
Those are OK as drivers.
For generic PS drivers (to keep in stock), I'd suggest the BD139 and BD140. They're good subs and readily available (here, anyway).
Sorry I mean overload the Chip 494, if I install a1220 instead a1266, the a1266 could demand mor miliamps to operate, the ic Will be able to work ?, this extra miliamps posibly can overheat the Ic 494 damaging it prematurelly??
The IC won't see a difference. I've seen the SMD version of the 494 driving a 100 ohm load for 20 years and the ICs were perfectly fine.