I have another question: where can I reliably source 2SA968B/2SC2238 and 2SK213/2SJ76 transistors used in the driver stage to avoid counterfeits? Or are there any suitable replacement models? Thanks!
Hello,I want to replace the main filter capacitors of my P-300X. Do I only need to remove the screws on the copper busbar from the bottom, or are there other fastening components that need to be removed first?
Hi everyone, today, while servicing the machine, I discovered a pre-drive power circuit located behind the VU meters. There are three 2W resistors on it that exceed 100°C in temperature, and the heat doesn’t seem to decrease regardless of the bias setting. Is this normal? Has anyone ever measured this before? Thanks.
Nothing much, the machine is running healthy and in use. I just found a small question while doing some maintenance and tidying up. I’m just hoping someone with more experience can share some insights.
Did you destroy transistors (post 22) ?
Without schematic we can only speculate that the dissipation of these resistors is intentional, dropping voltage for an additional supply.
Without schematic we can only speculate that the dissipation of these resistors is intentional, dropping voltage for an additional supply.
No, everything is fine. I'm just a little worried about the temperature.
But it can run all day without any issues, so maybe I’m just overthinking.
But it can run all day without any issues, so maybe I’m just overthinking.
You can check the mains voltage setting is according to your condition at home.
However I can not recommend to do changes here without knowledge.
Why did you ask for specific transistors ?
You can always find help in this forum, but it is expected you put all cards on the table.
However I can not recommend to do changes here without knowledge.
Why did you ask for specific transistors ?
You can always find help in this forum, but it is expected you put all cards on the table.
I purchased this used P-300X about a year ago. After a thorough cleaning, it’s been performing very well without any issues. However, since the P-300X lacks technical documentation compared to some other models, it’s easier to worry about whether my settings are actually correct. That’s why I’ve been trying to verify things from multiple sources. Recently, I also looked for specific transistor models just to prepare in advance for future maintenance.
As a side note, after looking into it again, those resistors appear to be wirewound types, so the high temperature shouldn’t be much of a concern. I guess I was just overthinking it.
As a side note, after looking into it again, those resistors appear to be wirewound types, so the high temperature shouldn’t be much of a concern. I guess I was just overthinking it.
Have a look at the solder joints of components like this if they are easy to access for you.
I can not reommend to even look for obsolete semiconductors used here, you will not need them if you do not destroy the amp intentionally (careless sevice included) and what you get today on the market can not be compared to the stuff Accuphase used at the time.
I can not reommend to even look for obsolete semiconductors used here, you will not need them if you do not destroy the amp intentionally (careless sevice included) and what you get today on the market can not be compared to the stuff Accuphase used at the time.