I had a good look at both of the boards, cant find any thing amiss (BTW nice soldering), dont have eagle eyes.
Non-working board:
1.Pl check the pin 2 and 3 of op amp for any short, which may not be an issue anyway. try reflow of joints if you haven't done that already.
2. see if any of the transistor is exchanged, MPSA 42 to 92, BC327 to 337, IRFP9240 to 240, etc. + you may like to see if any of the semi is dud.
Working board.
1. like I said resistor values check based on the schematic for expected value (if any of the resistor are in parallel.
hope that someone like Mr. Mile is able spot something.
how is the DC offset behavior , might give some indication if the problem like with servo ckt.
Hi Prasi,
What cap did you plan for C10 and C11? That is on the low voltage circuit. You have it marked as 100u but it is a large footprint.
Thanks, Terry
Hi Prasi,
What cap did you plan for C10 and C11? That is on the low voltage circuit. You have it marked as 100u but it is a large footprint.
Thanks, Terry
I wanted to see if using higher value there could give better supply to i/p ckt like 470u being used in Bimo mod of FX-8. (But I never actually got around to testing it)
Just my thought, Mr. Mile's ckt uses 100u.
reg
Prasi
I wanted to see if using higher value there could give better supply to i/p ckt like 470u being used in Bimo mod of FX-8. (But I never actually got around to testing it)
Just my thought, Mr. Mile's ckt uses 100u.
reg
Prasi
Actually, Mile didn't use a big cap on the low voltage section.
Attachments
Actually, Mile didn't use a big cap on the low voltage section.
Ok my bad. It was my addition. Also added individual electrolytic caps on D of mosfets as a little reserve. Got the idea from one of the slewmasters. Amp will work just fine if one doesnt populate those electros as per Mr. Mile's orginal design.
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Power on and power down speaker thump
Hello Miles
Will this psu with protect also eliminate Power on and power down speaker thump.
Vikram
On this PCB exept PSU is short-circuit and DC protect, clip indicator...
Hello Miles
Will this psu with protect also eliminate Power on and power down speaker thump.
Vikram
Corrected Silkscreen pdf file for FX100 PSU.
Hello Sonal
Can you guide with proper wiring instructions for this psu.
Vikram
DEAR RESPECTED PLEASE SEND US PCB FOR F100 UPGRADED TO ATOM 600 ON YEAR 2015 BY MISLER MILES APEX. WE ARE HAVING PROBLEM WITH POWER SUPPLY OF THIS VERSION OUR LAB IS BARD DUE TO NOT HAVING THIS POWER SUPPLY WITH PROTECTION SCHEMETIC AND PCB LAY OUT.
LET US HELP WITH IT PLEASE.
AWAITING REPLY
LET US HELP WITH IT PLEASE.
AWAITING REPLY
This PSU and Protect circuit ca be used with any amplifier. Short-circuit protect based on Tandberg schematics is 100% efficacy.
how does this short-circuit protection works
Protection stk4048
hello good morning this protection can be used for aplificadores with stk 4048?
After 15 years work...
hello good morning this protection can be used for aplificadores with stk 4048?
FX-100 3 pair 70V version.
reg
prasi
HI prasi
have you sprint layout file?
thank you
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