i collect all parts already for sr800. project delay due to less time and did you fit ntc150k in sr 800.for real power don't use c5200 a1943 pair.thanks.
I am still waiting on the Mac97a parts to arrive. It is tested with the two transistor version.
My MA97a came in so I tried them. It takes over 6Vdc on the speaker jack to trip it. Worse than the BJT version.
Is that both + & - 6Vdc?
Swap the triac around by 180 degree.
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Swap the triac around by 180 degree.
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OK I inverted the triac. Now it will switch at -2v but still needs +6v to trip. This is probably fine for most amps but not really any advantage over the circuit using two BJT instead of the triac. One more thing I just noticed is that this circuit adds some noise to the ground on the amp. I think being connected to the transformer may be causing some issues. I will do more testing tomorrow and see if I can find a solution.
Blessings, Terry
Blessings, Terry
Ok. So swapping the triac around moved the operation to a different quadrant. The other thing to understand is when the triac fires it wont turn off until powere is turned off. That is when the dc fault goes away (for whatever reason) the dc detection circuit won't reset itself.
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I have a question about rectifier boards
Does adding more film Capacitor in parallel with large electrolytic make it sound better? brands are WIMA EVOX etc
Does adding more film Capacitor in parallel with large electrolytic make it sound better? brands are WIMA EVOX etc
more cap what do you mean.no sound quality depend on circuit topology.these cap have different role.important but not so much.
Hi Mile ,testing this mono protection board i see that to come in protect mode a d.c level + or -7v is necessary
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Hi Thimios, that is the same thing I experienced with the triac. Inverting it helped a little but the version with the two BJT's worked better IMO.
The question is what is the probability that the output of the amplifier have +/-7V DC offset. Many protections have similar circuit for dc detection (working amp have output DC offset about +/-50mV max and broken is on rail voltage about +/-50V). If necessary I can modify circuit to have the +/-1V DC sensitivity.