Power on probs and noisy sound - Worn out Capacitors?

[keith56]

Probably asking a silly question, but thought I'd ask before taking the CPC apart.
I'm
I haven't used it for a couple of months, and now its having a few problems.

when plugged in it seems to flick on and off really quickly causing the HXC floppy to make crazy beeping noises (At first I thought the power plug had a faulty connection or a dry joint)

After a while of me messing with it it seems to work, but then the sound is "hissy"

However, after a bit of use, the power is 100% reliable, and the hiss dies back.

Has anyone had the same symptoms? I'm assuming the Capacitors are failing on the CPC

[Audronic]

@keith56


Dirty Power switch most likely.
Try just turning on and off the power switch about 20 times " with the power off " first
These can be "Carefully" opened up and cleaned.
Try that .
Good luck   Ray

[||C|-|E||]

I would say that the switch is actually a good candidate, yes... it is very strange to find bad caps in a CPC or Plus 

[keith56]

Well, I tried the power switch trick, and it didn't fix it, but it seems the problem was close.


I swapped the power supply, I don't have a proper monitor so I use a random one.


and that fixed it, the socket is really dirty (And cleaning it with isopropyl alcohol didn't seem to help  )


So it seems that either my usual power adapter has worn out, or a there is bad connection on the socket which works better with the alternate one.


Either way, the problem is fixed, without me having to use my dubious soldering skills on the CPC!


Thanks for the help,


Keith

[Bryce]

How many amps did the old PSU claim to be able to deliver? It might be a case of the PSU being too close to its limits. Does the problem go away when the HxC isn't connected? Or is it perhaps a dodgy Chinese PSU with cheap capacitors that are starting to fail (or their ESR is starting to rise) which would cause the 5V rail to become noisy.

Bryce.

[keith56]

The old one that no longer works is 2A


the one that does work is 2.5A


I know the 2A is close to the line, as it can't power the FDD on my CPC plus (A real fdd).. but it used to power the 6128 properly, so I guess its wearing out or something (It seems to be ok after a few seconds of "Warming up")


Thinking about it that does make sense as the cause of the problem, as I noticed today that the screen is working ok (I use a RGB->VGA converter box and it takes a little time to init and set up on my TV so I didn't notice before) when the Hxc is making noises so it seems the CPC CPU hardware itself works OK, but the FDD and CPC sound are acting up.


I'll have to use the 2.5A from now on, its a bit of a pain as it has a UK plug on it so I have to use a converter, but it seems the 2A is not usable any more

[Bryce]

I assume you are in Japan as your profile states, so why don't you just buy a 3A 110V Japanese PSU? They're not expensive.

Bryce.

[keith56]

Yeah, I think that will be best, I can see one for sale  on Amazon which is cheap, and it would be nice to have 3A so this can't happen again!