Panasonic NV-MV20 - UK Vintage Radio Repair and Restoration Discussion Forum

andyw25 · 23rd Sep 2014, 8:57 pm

Hi all, have a problem with this vcr, one of the newer types.

It had a leaky capacitor so this was replaced and it just hasn't run properly since.

It accepts a tape but immediately laces up and begins running. The counter seems to be going too fast almost as tho the recorder is stuck in picture cue, when it is doing this none of the functions respond, not even eject.

Even turning into standby it keeps on running and the only way to stop is to unplug the unit

Does anyone have any insight to the issue?

Thanks, Andy

Nuvistor · 23rd Sep 2014, 10:18 pm

Only item I can offer is did you clean the PCB of all the leaked electrolyte and check that it as not rotted any other components/leads etc.
Frank

HamishBoxer · 23rd Sep 2014, 10:31 pm

I will second that and hope the eprom etc has not been scrambled.

andyw25 · 23rd Sep 2014, 11:40 pm

It was in the power supply section but it's the modern type recorder with one single board. There was no leakage onto the board thankfully, it had only just started out of the top of the capacitor so I managed to remove it and replace it before any damage was done to the board.

On a very rare occasion tape speed does slow and playback can be achieved but then it goes back to normal once stopped.

AC/HL · 23rd Sep 2014, 11:52 pm

If the capacitor was bulged enough to split the top, I'd replace all the others of the same make/type in the PSU at least.

IanNVJ35 · 23rd Sep 2014, 11:58 pm

Can you confirm that the lid is on - these symptoms are exactly like when outside light gets to the PSU.

nigelr2000 · 24th Sep 2014, 11:48 am

Yes second that, i have been caught out on vcr's when i used to service them for a living because my bright bench light was triggering the tape end sensors making it think it was on the leader section and going into a slow fast forward (if that makes sense).
Try it with the lid on

HamishBoxer · 24th Sep 2014, 12:55 pm

Panasonic K series come to mind for that trick.

andyw25 · 26th Sep 2014, 8:22 pm

Just a little update, feel a little daft admitting but it was in fact the light getting in due to the lid not being refitted after the capacitor replacement. Lid now refitted and all tested perfect

Thanks for the help guys

23rd Sep 2014, 8:57 pm	#1
andyw25 Pentode Join Date: May 2009 Location: Dumfries & Galloway, UK. Posts: 101	Panasonic NV-MV20 Hi all, have a problem with this vcr, one of the newer types. It had a leaky capacitor so this was replaced and it just hasn't run properly since. It accepts a tape but immediately laces up and begins running. The counter seems to be going too fast almost as tho the recorder is stuck in picture cue, when it is doing this none of the functions respond, not even eject. Even turning into standby it keeps on running and the only way to stop is to unplug the unit Does anyone have any insight to the issue? Thanks, Andy

23rd Sep 2014, 10:18 pm	#2
Nuvistor Dekatron Join Date: Aug 2013 Location: Wigan, Greater Manchester, UK. Posts: 9,433	Re: Panasonic NV-MV20 Only item I can offer is did you clean the PCB of all the leaked electrolyte and check that it as not rotted any other components/leads etc. Frank

23rd Sep 2014, 10:31 pm	#3
HamishBoxer Dekatron Join Date: Aug 2007 Location: W.Butterwick, near Doncaster UK. Posts: 8,935	Re: Panasonic NV-MV20 I will second that and hope the eprom etc has not been scrambled. __________________ G8JET BVWS Archivist and Member V.M.A.R.S

23rd Sep 2014, 11:40 pm	#4
andyw25 Pentode Join Date: May 2009 Location: Dumfries & Galloway, UK. Posts: 101	Re: Panasonic NV-MV20 It was in the power supply section but it's the modern type recorder with one single board. There was no leakage onto the board thankfully, it had only just started out of the top of the capacitor so I managed to remove it and replace it before any damage was done to the board. On a very rare occasion tape speed does slow and playback can be achieved but then it goes back to normal once stopped.

23rd Sep 2014, 11:52 pm	#5
AC/HL Dekatron Join Date: Nov 2003 Location: Heckmondwike, West Yorkshire, UK. Posts: 9,642	Re: Panasonic NV-MV20 If the capacitor was bulged enough to split the top, I'd replace all the others of the same make/type in the PSU at least.

23rd Sep 2014, 11:58 pm	#6
IanNVJ35 Heptode Join Date: Mar 2010 Location: Hemel Hempstead, Hertfordshire, UK. Posts: 848	Re: Panasonic NV-MV20 Can you confirm that the lid is on - these symptoms are exactly like when outside light gets to the PSU.

24th Sep 2014, 11:48 am	#7
nigelr2000 Heptode Join Date: Nov 2008 Location: North Walsham, Norfolk, UK. Posts: 900	Re: Panasonic NV-MV20 Yes second that, i have been caught out on vcr's when i used to service them for a living because my bright bench light was triggering the tape end sensors making it think it was on the leader section and going into a slow fast forward (if that makes sense). Try it with the lid on

24th Sep 2014, 12:55 pm	#8
HamishBoxer Dekatron Join Date: Aug 2007 Location: W.Butterwick, near Doncaster UK. Posts: 8,935	Re: Panasonic NV-MV20 Panasonic K series come to mind for that trick. __________________ G8JET BVWS Archivist and Member V.M.A.R.S

26th Sep 2014, 8:22 pm	#9
andyw25 Pentode Join Date: May 2009 Location: Dumfries & Galloway, UK. Posts: 101	Re: Panasonic NV-MV20 Just a little update, feel a little daft admitting but it was in fact the light getting in due to the lid not being refitted after the capacitor replacement. Lid now refitted and all tested perfect Thanks for the help guys