meanwhile, after connecting input GND to PSU GND, output offset came down from 61mV to -4.5mV that is good. but input -9mV isn't solved.
Hi.
on +/- 75V rails, R24 and R25 (2/2k -2W) are getting too hot insofar as I can't touch them.
Should I use 4/7k instead of 2/2k ?
Thanks.
on +/- 75V rails, R24 and R25 (2/2k -2W) are getting too hot insofar as I can't touch them.
Should I use 4/7k instead of 2/2k ?
Thanks.
sir, can I use mjl3281/1302 pair instead of 2sc5200..because mjl's are genuine and also in my budget ..
Hi Mile, due to reliable and easy to mount properties I'd suggest to replace Q5 (BC517) by a TO-126 device like BD139 or something like that. What rail voltages would you recommend for obtaining 500 watts@4 ohms? I guess there should be +/- 68 to 70 volts, right? And, last but not least, where do I find PCB layouts for your B500P and DC555 boards, respectively, and the schematics and silk screen for the latter one, too? With regards!
DC555
hi sir mile is this on apex DC555S design?
i think it's the same but cant find the 2pcs. IN4007 + 10K resistor connected to L+R amp.
or is it for 1 channel only?
can i use it without NTC 10K?
hi sir mile is this on apex DC555S design?
i think it's the same but cant find the 2pcs. IN4007 + 10K resistor connected to L+R amp.
or is it for 1 channel only?
can i use it without NTC 10K?
You can use it without NTC, DC555S is stereo protect and there is 1N4007, 10k and 100k add for second channel.
thank you sir mile,
but one more question i have made your APEX500 4 pairs almost done but was stacked coz i can not find the NSL 32 when i shoped for parts, will there be other option?
thanks again sir mile...
regardz
Hi Mr Mile, I want to make B500P MONO version. has it been tested? could it be done with 3 pairs of output transistors and a rail of +-70VDC for 250w/4ohms?
And the PSU specs would be a transformer 50+50VAC (3.5A)
And 15000uF+15000uF (total 30000uF)
Is it suitable for this amp?
Sorry for my english.
Thanks!
And the PSU specs would be a transformer 50+50VAC (3.5A)
And 15000uF+15000uF (total 30000uF)
Is it suitable for this amp?
Sorry for my english.
Thanks!
250W into 4ohms needs approximately ±56Vdc to ±58Vdc (38Vac to 40Vac @ ~500VA) and uses ~1200W of BJT output devices.
3pair of 200W gets you 1200W of total Pmax.
You definitely don't need 50Vac
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Conversion almost done...thank you sir Mile..this powered mixer is alive now using your wonderful class ab amp...
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Attachments
please kandimba attach the pcb files of the apex led light display for the front pannel