Thanks to Tea B I finally got a new mosfet in there,everything light up Now.now need some adjusting.Now my power supply voltage drop to 37 voltage at DC end when hook up and both fire up?
lapsan
You mean raw DC at board input level? That's too low. If you got Vdrop on the 15Ω resistors suggesting about 100mA through each, then the boards are OK but the raw PSU has a mistake or some wrong spec.
Thank you,i got it back to 48volt at the input,on one rail is 34.6 volt and on another rail is 30.6 volt so far,i'm trying to bring that up to match the other side.
Regarding my 20x Hong Kong eBay purchased 2SK117GR:
I am getting between 4mA and 6mA IDSS, so all within GR spec.
Most obvious quality is almost zero thermal drift, and immediate reading does not change, as compared to almost opposite experience testing K170 fets. Is this a sign that they are genuine?
I am getting between 4mA and 6mA IDSS, so all within GR spec.
Most obvious quality is almost zero thermal drift, and immediate reading does not change, as compared to almost opposite experience testing K170 fets. Is this a sign that they are genuine?
Hi Hikari1.
Would you mind upload a drawing of how you place the components on your protoboard?
It would be very appreciated
Regards
Turbon,
Here is what I am thinking for layout. IT IS UNTESTED, there may be mistakes. It is sized for 7x9cm protoboard. The gray area is heatsink. Feel free to comment or give suggestions.
Attachments
Hi Hikari1.
Looked it thru and I believe it will work. The only mistake is that the cap marked C1 100uf close to Q2 is actually C2.
Regards
Attachments
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Building the pcb version...
Well, I decided to build a 40db gain version using the pcb's instead as I have a kit. Saved it for another 63db build but as I have oldie goodie mm carts I wan't to give them the respect of something documented good. It feels as a more secure path with support from the designer.
Regards
Well, I decided to build a 40db gain version using the pcb's instead as I have a kit. Saved it for another 63db build but as I have oldie goodie mm carts I wan't to give them the respect of something documented good. It feels as a more secure path with support from the designer.
Regards
Actually, mine is a 40db version too. PCB is a good idea, when I started mine the group buy was not going yet, and I wanted to use batteries initially because I didn't have a suitable transformer or case. But yes, the PCB should be good.
I am using a Ortofon 2M bronze on a Rega P5 with the Nfet phono (using batteries) now. It is amazing. I hope the shunt is better than batteries but it will be worth it just to not have to monitor the voltage and replace batteries all the time.
Hikari1, I'm sure that the shunt will outshine the batteries. I'm equally sure that the whole will astonishe you in it's brilliance. I choose the easy path as I have most of the parts needed.
Regards