Strange PVR behaviour

Dying capacitor in the power supply?

Any software updates recently? Out-of-interest, can you change to HDMI 2 (or even 3) and see if the problem occurs?

I had an issue about 10 years ago with my Panasonic TV and PVR, in that the PVR switched the TV to the PVR's HDMI input whenever it came out of standby for timer recording, so interrupting anything I was watching on TV at the time.

Panasonic support suggested changing from HDMI1 to HDMI2, and that solved the problem. Rather confusingly, Panasonic's explanation for this was "the HDMI2 socket of your television will be the most sensitive one to any signal it may receive from any external device connected to it." If it was the most sensitive, I'd have thought it was more likely than HDMI1 to respond to any signal from the PVR!

(NB I downloaded your TV manual and for a Panasonic manual thought it was rather poor in that it didn't show exactly where the HDMI connections were and what, if anything, was the difference between them)

If you find any good PVR - satellite or Freeview - you'll have done well, as it all seems to be moving to streaming today. :-(

Caps dying, don't have to be just in the power supply. Capacitor failures can be via stress (PSU output caps and ripple current), but in the Bad Cap era, simple chemistry problems caused all of them to fail. There could be failures all over the place.

On SMPS, a failed capacitor can overload an adjacent MOSFET and inductor, burning them. The main problem with this, is the damage can be bad enough, you can't get a part number off the items, to acquire replacements.

As a capacitor is circling the drain, a little puff of gray smoke will come out of them at startup. If you see that, it's time to stop using the item, until you replace the caps in it.

The crack in the top, can leak a brown liquid. The liquid can corrode the copper tracks. With severe enough damage of that kind, an item can be a write-off. If the capacitor has dried out, there might be (less) liquid to pour down the side of it.

Paul

It can be worse than brown liquid. A capacitor failed in my HP digital storage 'scope, leaking a colourless and almost invisible liquid into the pcb. Even when dry, it leaked enough current to affect the division ratio of the feedback resistors in one of the power supply regulators. Replacing the capacitor AND cleaning the pcb fixed the problem. John

There's a particular capacitor that often fails. I replaced it in mine and it's been fine ever since.

It's surface mount, but I rep;aced it with an axial lead one as it was easier.

Thanks Bob. That looks suspiciously like the fault I'm seeing. When it becomes an unbearable nuisance, I'll give it a try.

Streaming has killed the market for PVRs, or shrunk it considerably, so manufacturers are not rushing to develop new models like they used to. The Humax Aura was released at the end of 2020 and is still available, remaining the only consumer PVR with three tuners. (I have an Aura, from 2020, that I'm very happy with, but a few months ago it started rebooting on switch-on, and powering back on during switch-off, issues that I fixed by changing the switch-on/off sequences on my Harmony remote.)

It's an easy fix. I think I had to remove something inside to improve access, but that was simple too.

I found I was having to have several goes by the time I decided to fix it.

Wahey! Fixed it! Now working as it used to, with no repeated re-boots. A bit of a fiddle though. My soldering skills are pretty minimal, and the components on printed circuit boards are so tiny these days...

Thanks once again for your help.

No problem. Yes, it is a bit, but I've been soldering for 60 years!

Just leave the Hummy in standby, apart from when you want to watch a recorded program.

Otherwise just use the Panny as a normal TV

He's fixed it now.

Which could lead to more components or the hard disk failing.

I once had a Topfield PVR and when one of the power supply capacitors started to fail it started to take down the 5V supply but initially not enough to stop the box working. The 5V output was the feedback reference for the switched mode supply which attempted to compensate by driving harder causing other power supply voltages to rise. If the capacitor in the 5V output continued to fail one of the other supply voltages became so high (by an extra 50%) it took out a transistor responsible for supply 20V(ish) to the tuners.