Panasonic DMR-E75V fault
 

Although this probably doesn't really count as true vintage equipment, I was hoping one of the learned people on here might have come across this before.

the DMR-E75V is a combined VHS and DVD player / recorder. I've had it for many years and currently use it mainly for digitising VHS tapes either to my computer or direct to DVD.

A while ago it developed an intermittent fault when it would power off when brought out of standby and would only power back on when unplugged and plugged back in a few times

The fault has now developed so that it will not power on at all when plugged in.

I have seen several of these machines for sale for spares or repair with a fault described as "will not power on" so I am guessing it might be a common problem.

I suspect a power supply fault but am unable to find any service details about this model. I can find a manual for the DMR-E75VP but that seems to be a very different machine with a HDD.

If anyone has knowledge of this I would be very grateful for any gems of wisdom. Even a circuit diagram would be useful.

Re: Panasonic DMR-E75V fault
 

Possibly, Elektrotanya has a circuit. Apart from electrolytics, if it uses an STR-G switcher IC, that would be suspect as well.

Re: Panasonic DMR-E75V fault
 

Sounds very much like capacitor plague (leaking electrolytics). Look for bulging radial mounted capacitors with traces of dried brown electrolyte on the top surfaces.
I've lost count of the number of devices over the past few years seen with this fault. My own DMR-EZ45V developed problems, and this was to blame. You can get complete capacitor repair kits for Panasonic recorders on the internet.

Re: Panasonic DMR-E75V fault
 

Thank you for your replies.

Yes - there is at least one electrolytic with brown deposits and another which is beginning to bulge so that is very likely the problem.

I did not know that replacement capacitor kits were available - I will look out for those.

I haven't yet tried to remove the power supply board as I was hoping to get hold of a servicing manual to undo things in the best order (it is nicely "knitted" together) but I will get the replacement capacitors and take it from there.

Thank you once again.

Re: Panasonic DMR-E75V fault
 

They are great fun to strip down and watch any ribbon cables.There will be several out of spec caps and maybe a repair kit available on eBay.

If not then one of the Panasonic kit suppliers will very often make you one up.

Re: Panasonic DMR-E75V fault
 

Thank you - yes, I'm looking forward to repairing it but its such a nice machine (when it's working!) that I don't want to risk doing unnecessary damage to it.

It is the flimsy ribbon cables and the other board to board plugs that I'm most nervous about.

Re: Panasonic DMR-E75V fault
 

Hi Tony,

Yes. Dried out caps on the power supply. However, I remember there are two somewhere near the front of the main board which dry out; you cannot see them until the whole of the unit is stripped down.

My service manual is around 5MB, so I cannot post it here.

Kevin

Re: Panasonic DMR-E75V fault
 

Thanks, Kevin - PM sent

Re: Panasonic DMR-E75V fault
 

I replaced the suspect capacitors and it is as good as new!

Thanks once again for the helpful comments.

Re: Panasonic DMR-E75V fault
 

I had problems with my Panasonic, just one replacement cap on the PSU and has been working flawlessly ever since. see here :https://www.vintage-radio.net/forum/...d.php?t=149912

:beer:
Mark

Re: Panasonic DMR-E75V fault
 

It was certainly an interesting exercise to get the board out but it all went back together again with nothing left over ;)

I only replaced two capacitors in the end - each one 1500uF, 16V which I replaced with 25V versions. All the other one's seem fine and the machine now works as well as it ever did.

Re: Panasonic DMR-E75V fault
 

Good machines and good move as I have done in the past upping the capacitor spec a bit.

Re: Panasonic DMR-E75V fault
 

Working voltage isn't the most important spec here as they are likely to be on a 12V or lower rail. Impedance and rated life are the most important. That said, a 25V electrolytic will often have a lower impedance than the 16V one since it has a somewhat larger active area. Within the same capacitor series, impedance is often given as a function of physical size, the larger capacitor having a lower impedance.

Re: Panasonic DMR-E75V fault
 

Hi Maarten

Thank you for the word of wisdom.

I am always impressed by both the breadth and depth of knowledge of the members of this excellent forum.