Phoenix Gold Phorum

I'm repairing a Phoenix Gold Ti2 1300.1 and have found several faulty components.
Among them is diode D21 (next to transistor Q81).
It has failed short, so I have no way to identify what type of diode it is.
All I know is that it's a MiniMELF with a blue stripe at the cathode end.
Can anyone tell me what this diode is meant to be?

It's a 12v zener diode.

Thank you so much.

I've gotten this amp into much better shape, but it still powers up into protect mode (red LED).
Are there any particular sections/components I should focus on?

I've only worked on a few of the newer aamp PG products, but they are almost all common Korean designs with a bit nicer lipstick on them.

You are going to have to figure out what is holding it in shutdown. Without a lot more information and without knowing your skill level or available tools, there is no real way for anyone to help troubleshoot it over the internet. If you are a beginner, then I'll say right off the top that class d amps are not something to cut your teeth on.

That said, if the amp had any failed outputs, the ir2184s is probably failed now too. If you are a beginner, you are going to torch a lot of ir2184s driver ics. They are super fragile. Even If you replaced it, it's no guarantee that the new one survived. If you replaced it with a irs2184, then it's probably bad. On paper they are pin compatible, irl they rarely live long happy lives. If it sounds like I'm speaking a foreign language right now, then definitely pick an easier amp to learn on...

Sam Vennard (barevids YouTube channel) did a repair of a ti2 2000.1 a while ago. It will be a very similar amp and may be a valuable watch.

Good luck,
Jason

Cheers for the info.

I finally had time to get this off the shelf today.

As it turns out, it was going into protect mode when there was no speaker connected.
When I connect a speaker and then power it up, the LED is red for a couple of seconds then turns blue.

I will continue this repair and post the results.

I have removed the rectifier diodes from the board. It runs in a stable fashion (using 320mA when run at 9V, or 420mA when run at 12V).
The LED is blue.

When I ran it with the diodes installed, it would use as much current as I gave it, including all the way up to 3A (for a second, before I shut it off).
So I think there are still faults present.

I found a diode (D17) that has failed (shorted out).
There are 3 of these types of diodes present (D17, D24, D25) and they are all in close proximity to the IR2184S chip.
The other 2 are fine.
They are SMD diodes made by ON Semiconductor and say "225" and "U1D" on them.
Does anyone know what these are, or a suitable equivalent?

I have determined these diodes to be ON Semiconductor MURS120T3G.

I have managed to get this amp working.
Thanks again. Couldn't have done it without your help.