Lines from HV to fets must be short and strong, and from fets to fuse also. HV line after fets no need to be strong...
No, for 55V U can use: IRF1010, IRF3205, IRFZ44, IRFZ48...
For over 55V use IRF2807, IRF1407
If U want use TO247 use: IRFP044, IRFP048 or IRFP054
Regards
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Yes this is the best method of mounting transistors, but best use TOSHIBA, this ST are probably fake.
Regards
ST and Fairchild are both making licensed copies - if it comes down to getting ST through a reputable distributor (in full 25 pc tubes) or getting loose pieces of "Toshiba" from God-Knows-Where, I'll take the ST. They're cheap enough to break one open anyway - and you still have multiples of 4 or 6 to put in parallel.
Use the values originally published, unless your testing reveals that it's not optimum.
hi
greetings every one thanks for all your suggestions st transistors bought
from st dealer packs of 25 have toshiba about 30 pairs feel they are not genuine
exactly like apex audio has shown in earlier post will use mjl 21193 mjl 21194
once amplifier comes on. FIRST h class so going exactly as specifed
few qs for general knowledge
1 how does 4 pairs produce so much output do h class produce less heat
2 what will be ac voltage signal at output approx
3 built dx turbo 10 output pairs can h class swiching rail be applied to it
using rail switching
4 can this power supply be used only for testing purpose will make 40 volts into 4 torridal once amplifiercomes on
thank you apexaudio wg ski workhorse for all your suggestions and help thanking you
andrew lebon
greetings every one thanks for all your suggestions st transistors bought
from st dealer packs of 25 have toshiba about 30 pairs feel they are not genuine
exactly like apex audio has shown in earlier post will use mjl 21193 mjl 21194
once amplifier comes on. FIRST h class so going exactly as specifed
few qs for general knowledge
1 how does 4 pairs produce so much output do h class produce less heat
2 what will be ac voltage signal at output approx
3 built dx turbo 10 output pairs can h class swiching rail be applied to it
using rail switching
4 can this power supply be used only for testing purpose will make 40 volts into 4 torridal once amplifiercomes on
thank you apexaudio wg ski workhorse for all your suggestions and help thanking you
andrew lebon
Attachments
Use MJL21193/MJL21194
2 for 900W 4R output ac voltage is 60v RMS
4 this PSU will be OK
Regards
I suggest U to use dual OP like in original circuit or 43k must replace with 15k and 33pF with 150pF on your PCB. Both line from 2W 4R7 to 47nF must be short. U must add VI limiter if not use original protect circuit PCB.
Regards
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A 2-step class-H produces 30% less heat than same rating class-ab and a 3-step class-H produces 45% less heat.
It also helps in handling reactive loading of output stage, since the VCE across transistor reduces very much in Class-H, Hence less heat and much safer operation.