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Start Up Fails When HDD Connected

Oliver said:
We explained at the time it was not a good idea to replace a 4.7uf electrolytic capacitor that is 25v on this machine. The original is rated at 35V 4.7uf and a smd Capacitor. You agreed for us to put our part on. You should not change a smd capacitor for a through hole version. You should replace like for like. You can put a higher voltage on it but not lower. Capacitance should be the same, not lower or within 10% higher...
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As a general rule yes, but not when you know the circuit parameters. 35V is unnecessary in this case, even 25V is overkill.

SMD: nice if you can get one, but if you can't you have to make do with what you can get – ie a radial leaded. It is also difficult to fit SMD components without specialist tools.

Nobody here suggested you take it to a repair shop – if you had mentioned it I would have told you not to waste your time and money (or theirs). It would either be very expensive, or bodged as a favour. Replacing with a second-hand HDR-FOX is the most viable option, and replacing the capacitor is last-ditch for when there is nothing to lose. Without further detailed testing there was no certainty that replacing the capacitor would cure the problem (it might not even have been the same problem).

It is not correct there were no schematics, there are sketches of the circuit topology in this area up-thread. But nonetheless, I'm quite sure the repair shop offered you no guarantees, and made their best effort based on the limited information you provided. They would not want to be spending time reading lengthy forum posts, nor engaging with the discussion. We could have advised, but it's unreasonable to expect.

Basically they're saying they did what you asked them to do and washing their hands of it, and I don't blame them one iota. You were being naïve by complaining, and particularly naïve griping in this thread when you know they've seen it.

We are enthusiasts, you are a consumer. Enthusiasts go to lengths inappropriate for a consumer, even inconvenience. As a consumer, a PVR is an off-the-shelf item: you buy one, you use it until it breaks, becomes obsolete, or you decide to get another one.
 
Oliver said:
The said one of the solder pads came off so they had to use a wire.
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Looking at the pictures you have provided the green wire has not been prepared, fitted or soldered very well. I would be embarrassed if I had charged a fee for that workmanship !
 
Stummery said:
Looking at the pictures you have provided the green wire has not been prepared, fitted or soldered very well. I would be embarrassed if I had charged a fee for that workmanship !
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Precisely my thought on seeing that picture. I'd be embarrassed if that were my work and I'm strictly a hobbyist. And it would be normal to fit solid core wire for a repair like that, not multi strand as they have done with attendant risk of a strand coming loose and shorting to something else.
 
Newcoppiceman said:
Replacing the Mosfet (U24) and the 4u7 cap in the HDD 12V switching circuit has fixed our faulty PVR; it is an ex-faulty PVR. The conclusion, then, is that the likely culprit for any problem embraced by this thread’s title (or something similar, especially if temperature-related) is that 4u7/35V SMD cap. I replaced it with a 4u7/25V conventional electrolytic (there’s never more than 12V across it, so the derating is ok). Remember, I blew-up the Mosfet (still don’t see how) - it wasn't responsible for the original fault.

The details of how the PVR detects a problem with a slow-starting HDD 12V and forces a restart (and why, at other times, such as for scheduled recordings from standby, it’s not bothered) remain a mystery. As does why it boots ok with the HDD disconnected.

I joined this thread at post #67 and we’re now at #122. Sorry about that – but I thought present and future readers would benefit from a blow-by-blow account of fixing this fault.

Removing the HDD supplies' test wires and replacing the SPDIF socket will complete the job for me.
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Just fixed my PVR that was constantly rebooting and wanted to thank you for the advice. Just wish I had seen this before dumping my last machine that had the same problem.
 
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