I have a 18 0 18 dac supply if I measure 30 across the 18 and 18 ac have I got it right? The toroid might be closer to 15. I've never built a split rail. I googled plenty of schematics. It hasn't blown the fuses I clipped in..Are the two tappings phased right?
If it's right I want to plug in a discreet dual hdam next. I don't see a big coupling cap so I'm guessing it might be direct coupled.
Classic good sound PCM58 18BIT decoder board DAC upgrade PCM63|Home Automation Kits| - AliExpress
I hope I'm not breaking any rules. I will add the dac in case someone wants to search it. I think it could be ok. Classic good sound PCM58 18BIT decoder board DAC upgrade PCM63
If it's right I want to plug in a discreet dual hdam next. I don't see a big coupling cap so I'm guessing it might be direct coupled.
Classic good sound PCM58 18BIT decoder board DAC upgrade PCM63|Home Automation Kits| - AliExpress
I hope I'm not breaking any rules. I will add the dac in case someone wants to search it. I think it could be ok. Classic good sound PCM58 18BIT decoder board DAC upgrade PCM63
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You need to be specific where have you measure the supply was it the toroid secondary or was it on the PCB.
If it was on toroid how did you measure it with a multimeter (I presume) DC or AC volts?
If it was on an AC setting measured at secondary then 15 volts is OK.
If it was on main board where did you measure it after the rectifiers or after the regulators?
If on main board after the rectifiers it should be (considering toroid providing 15 volts at secondary) (15*1.1414)-1.4, should be around 18-19 volt at no load.
After the regulators it should be +/-15 volts or +/-12 volts depending upon the regulators used on analogue pins.
and +5 volts for digital supply rail.
If it was on toroid how did you measure it with a multimeter (I presume) DC or AC volts?
If it was on an AC setting measured at secondary then 15 volts is OK.
If it was on main board where did you measure it after the rectifiers or after the regulators?
If on main board after the rectifiers it should be (considering toroid providing 15 volts at secondary) (15*1.1414)-1.4, should be around 18-19 volt at no load.
After the regulators it should be +/-15 volts or +/-12 volts depending upon the regulators used on analogue pins.
and +5 volts for digital supply rail.
Hi rehanabid yes I measured multimeter AC setting across the green socket on the board where the 4 15v ac trans secondary coil wires(two coils) enter the board (in the picture)(3 pin socket) to go to the diodes. I have joined on the centre terminal 2 windings,one of each coil (15 volts ac). One winding in phase and one in the reverse phase. I then hooked the remaining two coil wires to the outside terminals where I Am measuring. I have measured 30 volts ac across the outside terminals (green socket).
Thanks for the help. There is not even a led on the board to indicate its on. The board is not earthed yet or hooked up. Just the two 15 volt toroidal trans coil windings wired out of phase and joined on the centre terminal plus the separate single 2 wire 9 volt ac input.
Thanks for the help. There is not even a led on the board to indicate its on. The board is not earthed yet or hooked up. Just the two 15 volt toroidal trans coil windings wired out of phase and joined on the centre terminal plus the separate single 2 wire 9 volt ac input.
As per requirement of the board you need to have matched 15 volts dual ac and a single 9 volts ac line.
If your DAC is working then you are good. There seem to be 5 voltage regulators on the board if you about each of them you may check output voltage of each.
BTW lower voltages are less of an issue compared to higher than required voltages, say you “might” blow the circuit if you connect a trafo of say 28+28.
Current requirement is above 0.35 amp if your trafo has a rating above this then you are good.
If your DAC is working then you are good. There seem to be 5 voltage regulators on the board if you about each of them you may check output voltage of each.
BTW lower voltages are less of an issue compared to higher than required voltages, say you “might” blow the circuit if you connect a trafo of say 28+28.
Current requirement is above 0.35 amp if your trafo has a rating above this then you are good.
I tested regulators and got 12 and 5 volts so I added a earth and put it into my system. It sounds much more close and warm in the vocals than my ak dac with dc op amp. Its sounds on par and similar to my pcm1702 dac with class A fet output. The bass seems a little weak. I will try some difference op amps after it runs in. I think for the price it might be worth using. Thanks for the help rehanabid!