Hi, I too would like to upgrade power supply, upgraded transformer to toroidal and it sounded terrible, pre- amp became very hash to listen to. Quickly reverted back to old transformer, I realize now it would benefit from better power supply. My DH- 101 in stock form has no hum on line stage when volume is turned up full. No music. Phono stage has small amount of hum after ¾ volume with turntable plugged into source ,none without table plugged in.
https://picasaweb.google.com/113336685910601049348/Desktop?authkey=Gv1sRgCNG5_dbT2qrlTA#
Yesterday I returne original preamp transformer and hum is gone, it seems unlikely that the hum coming from the toroidal transformer and I still can not believe it.
I'm sure I am missing something but I tried to bypass the switches for phono input but I get no sound when I do. Any ideas? I am going through the dh-102 mc option if that makes any difference.
I'd love to see how you are connected DH - 102 MC phono preamp if you can describe it in more detail.
I remover wires from phono 2 inputs and placed input wires from 102 there. I put output wires from 102 to phono button. Power supply wires go to empty holes next to color coded wires on power supply. I just don't know where the mute wires go. And they are shorter than the others. But there is a hum now. I tried going straight to the pcb where the phono input is and bypass the button switch but I get no sound when I do this.
Any Ideas?
Any Ideas?
I remover wires from phono 2 inputs and placed input wires from 102 there. I put output wires from 102 to phono button. Power supply wires go to empty holes next to color coded wires on power supply. I just don't know where the mute wires go. And they are shorter than the others. But there is a hum now. I tried going straight to the pcb where the phono input is and bypass the button switch but I get no sound when I do this.
Any Ideas?
Are you sure that the DH - 102 correct, it sounds to me you are connected well. You can try to attach it instead PHONO 1 input, output from the DH-102 attach to the point where they are attached C8-R15
"don't know where the mute wires go"
Where are c8 and r15? I can't seem to locate.
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.
Almost finished building a new preamp waiting for the Silver Mica and Black Gate capacitor.
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.
Ok. This is basically what I did before and I still have no sound at all. I can put it back running through the switch but I have loud hum when I do.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.
Why would it work through the switch which id using same input on the board and not work going straight to the board?
Ok. I now have a pdf of the full installation manual for the DH-102! I tried to upload it here but it is too large. Anyone that would like a copy sent to them, pm me your email address and I will send it to you!
Almost finished building a new preamp waiting for the Silver Mica and Black Gate capacitor.
Where did you get that blank PC-4 PCB?
Ok. I now have a pdf of the full installation manual for the DH-102! I tried to upload it here but it is too large. Anyone that would like a copy sent to them, pm me your email address and I will send it to you!
I'll try to find it on the internet do not worry.
I looked and looked and came up empty. I got it from another member here. ouimetnick was kind enough to email it to me. I would post it but it is too large.
Where did you get that blank PC-4 PCB?
My friend made it for me, we used high-quality material look much better than original.
I looked and looked and came up empty. I got it from another member here. ouimetnick was kind enough to email it to me. I would post it but it is too large.
Make the screenshot sheme and upload.
My friend made it for me, we used high-quality material look much better than original.
Did he use the toner transfer method? Does he have the file from the PCB software he used? I would like to make a new PCB for mine.
Sulzer-Borbely Regulator
Tried and tested Sulzer-Borbely Regulator Power supply, results are more than good no hum or noise perfectly stable, but I returned the original transformer is much more pleasant to listen to.
Tried and tested Sulzer-Borbely Regulator Power supply, results are more than good no hum or noise perfectly stable, but I returned the original transformer is much more pleasant to listen to.
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.
An externally hosted image should be here but it was not working when we last tested it.
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Did he use the toner transfer method? Does he have the file from the PCB software he used? I would like to make a new PCB for mine.
Yes he use toner transfer but I'm not sure for the film I can ask him.
DH-102 Manual Link: http://dl.dropbox.com/u/8335881/DH 102 manual.pdf
Everything is clear, but still don't know why do you have hum and no signal. try again all connections must be something.
Yes he use toner transfer but I'm not sure for the film I can ask him.
Okay, thanks. It would be a simple black and white print. As for your new power supply, it looks good. Lot more filtering and cleaning. Just an FYI: Erno Borbely designed the DH-200 and DH-101!
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