These tend to be unauthorised copies of Nelson Pass designs
Often with mistakes and if supplied with components fake and low spec items.
You may try to get support from the seller but that is often minimal.
Often with mistakes and if supplied with components fake and low spec items.
You may try to get support from the seller but that is often minimal.
I have the bare pcb affixed to use quality components ... and the psu scheme and preamplification and likely ... the problems I encounter are only in the recognition of the component indicated as 5551 and 431 that deal with the control of the relay volume. . xi 5551 I find only correspondences with 2n5551 but the pinout seems to me wrong. x 431 I can't find any matches .. thanks🙂🙂🙂
No reason to keep posting. You won´t get help on this forum for fake Pass products.:
As Colin said earlier... "Contact the seller".
As Colin said earlier... "Contact the seller".
If you dont get help from the supplier. A good Point to start is to make a circuit diagram from the pcb.
Only the volume Control part.
The chinese copycats will have cloned the preamp part 1:1 so there you could Need the Service Manual.
Maybe with a Diagram the parts you Looking for become clearer
This is what i would do.
Will be some work but...
...but better than nothing.
Hello Mr. Pass,
where can I find your current attention (=on which thread) if I want to ask your help regarding more current source measurements on speakers, in addition to the SPL plots from your article on this topic?
Thanks!
where can I find your current attention (=on which thread) if I want to ask your help regarding more current source measurements on speakers, in addition to the SPL plots from your article on this topic?
Thanks!
But... I would not start a thread just for my question, really. Is there any active thread with such subject that you are following and giving a bit of time, eventually could give me help?
Maybe PMs works better this case?
And btw, the red eyes may need some Visine, especially at mornings 🙂
Thanks,
Maybe PMs works better this case?
And btw, the red eyes may need some Visine, especially at mornings 🙂
Thanks,
If it is the board I think it is, you can use the original parts. I think the cbe pinout of the small transistors is different to the ztx450/550 layout so you will need to twist the legs (use teflon sleeves to avoid contact).
I suggest you take hi-res photo of the front and back of the board. Then in software make a mirror image of the rear. It is then easy to follow the traces and compare with original schematic.
I built an AP1.7 using a similar board that was given to me. Works great. Search for my postings to see more, also about finding (and fixing!) oscillations.
I suggest you take hi-res photo of the front and back of the board. Then in software make a mirror image of the rear. It is then easy to follow the traces and compare with original schematic.
I built an AP1.7 using a similar board that was given to me. Works great. Search for my postings to see more, also about finding (and fixing!) oscillations.
- Status
- Not open for further replies.