A powerFULL amplifier named Dirty Harry

[fotios]

Yea, tekko is right.
I know people that used 2SC-2SA transistors in output instead MJ15024-25 with success.

[jacobsetti]

Originally Posted by Tekko

i may be wrong but you should be able to use any power transistor as long as you use enough of them to stay within SOA at given supply voltage and load.

This amplifier output stage is in TEF ???

if it is can i use without it but how??

Replacement for MJ15020 and MJ15021

[fotios]

Originally Posted by jacobsetti

This amplifier output stage is in TEF ???

if it is can i use without it but how??

Replacement for MJ15020 and MJ15021

Output stage is a tripple darlington Emitter Follower (EF) arrangement.
Replacements for MJ15020-21 (tested with success) are MJL1302A - 3281A.

[vedmitraa]

Hi Fotios ,
Made your Amplifier long back ago, tested it up to 100-0-100 v d.c. It rocked even on 1 ohm load. I used 10 pairs of 15024-25 in output and 15022-23 in driving. Now I want to give it a try with 2sc5200 and 2sa 1943. Please guide me how many pairs I should use to get same power as 24 25 and up to what limit d.c. will be safer with sc-sa.Any more changes you suggest.
regards
Vedmitra Sharma

[AN214Q]

Originally Posted by zakzak

thank you for good amp .lm disign it like this and about 1 year its work so fine.its have,nt distortion so so fine

Dear Zakzak, Fotios,

Nice Amplifier, I'm just curious with this circuit. If you don't mind, in your measurement. How many voltage would be measured from Ground to base of 2SC5200/2SA1943 and Ground to base of MJ15024/Mj15025?


Regards...

[jacobsetti]

Originally Posted by fotios

Output stage is a tripple darlington Emitter Follower (EF) arrangement.
Replacements for MJ15020-21 (tested with success) are MJL1302A - 3281A.

can i use 2sc5200 and 2sa1943 instead of them?

[fotios]

Originally Posted by vedmitraa

Hi Fotios ,
Made your Amplifier long back ago, tested it up to 100-0-100 v d.c. It rocked even on 1 ohm load. I used 10 pairs of 15024-25 in output and 15022-23 in driving. Now I want to give it a try with 2sc5200 and 2sa 1943. Please guide me how many pairs I should use to get same power as 24 25 and up to what limit d.c. will be safer with sc-sa.Any more changes you suggest.
regards
Vedmitra Sharma

Hi Vedmitra
Thank you so much for your confidence in my amplifier circuit. Wow! +/-100Vdc supply rails, that is amazing! You should get around 2 X 550Wrms/8Ω! Congratulations.
Looking at the datasheet of Toshiba, 2SC5200 - 2SA1943 transistors are rated:
Pcase = 150W
Vce = 230V 2SC5200 / 200V 2SA1943
Ic = 15A
You should keep in your mind that ONsemi (former Motorola) transistors MJ15024 - 25 are unbeatable in robustness. Toshiba are some delicate and from those i remember from CREST PA amplifiers: max +/-90Vdc (90 - 0 - 90 V) and 9 pairs in output.

[fotios]

Originally Posted by jacobsetti

can i use 2sc5200 and 2sa1943 instead of them?

Yes, you could do this in the cost of a small loss in high frequency response.

[fotios]

Originally Posted by AN214Q

Dear Zakzak, Fotios,

Nice Amplifier, I'm just curious with this circuit. If you don't mind, in your measurement. How many voltage would be measured from Ground to base of 2SC5200/2SA1943 and Ground to base of MJ15024/Mj15025?


Regards...

Thank you AN214Q for your kind words. I haven't use 2SC5200/2SA1943, never. The only data i have is for the original circuit (pre-drivers MJE15032-33, main drivers MJ15020-21 or alternatively MJL3281A-1302A and output MJ15024-25). For the measurement that you ask:
With input shorted to GND and without load in output, the voltage between the base of output transistors and GND is:
+0.54Vdc at the base of each MJ15024 (NPN) and -0.54Vdc at the base of each MJ15025 (PNP).

[comasus]

Originally Posted by fotios

Yes, you could do this in the cost of a small loss in high frequency response.

Then what could be the frequency range ??