hi apex sir,
in my hand the 8.2k resistor not available, now i checked with 7.5k resistor, bias is ok,
92vdc power supply.
i feed 50hz sinewave and it clips 52v ac on output,
my 4ohm dummy load 250pcs x 1k x 5watts.
output transistors getting hot over 90degrees at 40v ac on out..
Amp must be cased air must flow with two fans thru heatsink.
is it fans push and pull?
is it 12vdc fan ok?
what is the size?
I prefer 48vdc 120x120mm fans. In BA2400 fans is push and pull 24vdc per side (left right), but 12vdc can be use with 15vdc regulated suply.
its detex 1.2kw,
only 2etd49 core used.
hi apex sir, what will happen if i change emitter resistor 10 ohm instead 1 ohm?
Is T2:A and T2:C reverted on schematic?
1 ohm is maximum value for emitter resistor you can use only value under 1 ohm but 0,47 ohm minimum.
hi apex sir,
what is the maximum temperature on output transistor to cut off?
if i give 95v dc power supply? is it clips at 80vac?
then how many watts for the 80vac out?
what is the maximum temperature on output transistor to cut off?
if i give 95v dc power supply? is it clips at 80vac?
then how many watts for the 80vac out?
hi apex sir,
what is the maximum temperature on output transistor to cut off?
if i give 95v dc power supply? is it clips at 80vac?
then how many watts for the 80vac out?
With +/-95V dc rail amp clip at about 60v ac or 900w/4R load.
hi apex sir,
i try with bd139,
same heat on outputs when 40vac on out. over 90 degree celcious.
it clips n 40vac.
3k3 must be replaced with 2k2 in bias circuit. Test amp with audio signal, sine way is only for short test.
i feed audio signal and checked, but it clips at 39vac,
and what is rail voltage drop at clip?
88vdc
Please check the clipping voltage, with different conditions:
1, No load,
2, 8ohms
3, 4ohms
Sajti
ok, i will check sajti,
is it ok to feed 50hz sinewave?
Yes, 50Hz will be OK.
Sajti
Hello guys !
I'm going to make this 1000w amp.
I have find on this thread the amp board, the dc protect board, the input display board and the psu board.
Something is missing for my build ? A soft start or something like this ?
And, for the PSU, it's two transformers 38V-0V-38V in serie for an output of +110V/GND/-110V ... it's right ?
And if it's good, what is the rated VA for one of the two 38V transformers ?
Thanks a lot and sorry for my english
I'm going to make this 1000w amp.
I have find on this thread the amp board, the dc protect board, the input display board and the psu board.
Something is missing for my build ? A soft start or something like this ?
And, for the PSU, it's two transformers 38V-0V-38V in serie for an output of +110V/GND/-110V ... it's right ?
And if it's good, what is the rated VA for one of the two 38V transformers ?
Thanks a lot and sorry for my english

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