Panasonic F65

[SpyguyUK]

Hi Everyone,

I have a Panasonic F65 VCR and there was a power cut the other day. The machine is now totally powerless. Does not power up.

Is this needing a capacitor, if so which one is needed? Or is it the fuse or something else?

The mains lead is working.

Thanks.

[vhs doctor]

Hi

In most cases this problem is due to electrolytic capacitors. Replace all of them in PSU

[dsergeant]

1uF 400V capacitor in the psu primary, very very common fault.

Dave

[HamishBoxer]

Yes, the 1uF causes total dead but the secondary caps can cause a few weird and wonderful faults be aware.

[SiriusHardware]

When this happened on my F70 many years ago the cause was heat-stress failure of a small electrolytic which is too close to a nearby heatsink.

It's in the startup circuit for the SMPSU, so the capacitor can have failed a long time ago and as long as the mains stays on, the SMPSU carries on running regardless. You only know there is a problem when the mains goes off for some reason, comes back on and the unit fails to start up again.

[HamishBoxer]

That is the 1uF Sirius and fitted on a few NatPan models I add. Thankfully, unlike a certain model of Amstrad sat box from way back, it does not blow up the power supply.

[HECTOR63]

Yes its a pretty straight forward job to complete and some companies used to do service kits for these and most of the Sonys aswell with various caps etc and all worked well after a good cleanup,as weve had some right stinkers in the past with the electroltic spill outs etc.But once completed and checked for belt service clutch torques and all that jazz they remained very good machines indeed.Very much a favourite of mine together with the Akai machines of the day.

[John123]

Yes if it makes a 'chirp' when power is applied it could be the Zener (crowbar) in the secondary, which in turn might also be caused by the secondary side caps. Worst-case scenario, the main regulator but sometimes you get a partially working machine with a bad reg (clock, but no button responses/ no power up with a dim operate LED permanently lit, no RF pass-thru, etc, etc).

[dj_fivos_sak]

Yup. As others suggested, it's more than likely a bad C1109 (1uF 400V) electrolytic in the power supply. I believe this cap is used as a "startup capacitor" to start the oscillator up when the unit is connected to the mains. Due to the age of the machine I would suggest measuring all caps in the power supply with an ESR tester and also look for physical leakage around the board.

Fivos

[SpyguyUK]

Hi,

Thanks Guys. You nailed it!

Problem solved however, even though I had some of those 1uF 400V capacitors I didn't replace it. I had another F65 that has a fault so I took the PSU from that and put it in this machine.

Before anyone says I may need to change the caps on this PSU I had changed most capacitors on it about 2 -3 years ago but that VCR still didn't work.

I may start a new thread but you may be able to help me on this also:

The original Panasonic F65 had a similar problem or I thought it was:

ORIGINAL FAULT

The VU meter was quite bright but sometimes, in fact quite often it goes dim. When I say dim it goes off completely and can stay off for a long time even if VCR is switched off then on again. It sometimes goes dim then back to being bright again.

If I give it a thud on side or top of machine it becomes bright again but sometimes only for a minute or two then it goes off again.

NEW FAULT

VCR does not power up at all.

I have changed most capacitors in the Power Supply/ PSU and even replaced PSU completely.

So, now I realize that the PSU on this VCR seems fine as it has brought the current one that I am using back to life what could the fault be?

Like I said the intermittent dim display (To all characters) was original fault. New fault is that it won't come on at all now.

Anyone able to advise me on this?

Thanks.

[toshiba tony]

Every one that came my way was the aforementioned cap. (in the case of dead machines) very good recorders.

[HamishBoxer]

Double check your work in case of a wrong value or wrong way round cap when fitting. It seems odd that the dim display has gone.

[John123]

Originally Posted by SpyguyUK

The VU meter was quite bright but sometimes, in fact quite often it goes dim. When I say dim it goes off completely and can stay off for a long time even if VCR is switched off then on again. It sometimes goes dim then back to being bright again.

If I give it a thud on side or top of machine it becomes bright again but sometimes only for a minute or two then it goes off again.

Sounds like a dry or cracked solder joint. Check all PSU soldering and also along the connectors. Do the same for the front display PCB.

If you can observe closely to see if the VFD's heater wires are glowing or not during the fault then that will narrow things down a bit.

[SpyguyUK]

Hi,

Thanks for replies but you may have misunderstood. The VCR des not power up at all now even though most caps were replaced on PSU.

I must have done the soldering ok as the same PSU works fine on my other F65.

Why would PSU work on one VCR and not the other? Both are F65's?

Could there be another reason for the fault and not the PSU at all?

Thanks.

[HamishBoxer]

Sorry, I see where you are now, this is very odd and certainly sounds like something other than the power supply. Check carefully all connectors and any suspect joints on same for starters .

[Welsh Anorak]

I suspect you might have a problem with the flexible cable that connects the PSU to the main PCB or one of the other ribbon cables, especially as it will have been moved about a bit. You also clearly had a poor connection somewhere before with the meter problems.