Panasonic NV-FS90 Dead - but not quite - UK Vintage Radio Repair and Restoration Discussion Forum

oerg866 · 14th Jan 2014, 7:45 am

Hi.

My Panasonic NV-FS90 has had some problems. When I got it several months ago, it had the audio muting problem, which I fixed and then put the unit on a shelf because it has lots of those tiny white spot dropouts all over the image.

I wanted to take a look at that today, but the unit is dead. When I plug in the power, the LED is on, the Display shows the volume meter (nothing else!!) And the head drum spins up with a very worrying noise (like an "eeeeehhhhhh").

So far I checked the power supply and found two bad capacitors (the 1µF 400V and one 100µF 50V). Could these be causing it?

As far as I can see the 1µF cap would have caused the unit to be dead entirely, no?

Cheers,
Eric

vhs doctor · 14th Jan 2014, 11:16 pm

If the capacitors are responsible to supply the servo or the syscon circuits they can cause these problems it is better to recap all the PSU.

Gillian · 15th Jan 2014, 12:28 am

I agree entirely with vhs doctor.
When the electrolytics on the secondary were checked and removed there was an accompanying smell of electrolyte and leakage on the board.
This job was quite an everyday occurance in the Panaasonic service centre I worked in.
A lot of fault symptoms were caused by excessive hf ripple on supply lines.

oerg866 · 15th Jan 2014, 9:39 am

Thanks for your replies,

I will replace all the lytics on that PSU. Meanwhile got an NV-FS1 coming with less than 100 hours on it. That thing ought to work for sure, haha

Cheers!

14th Jan 2014, 7:45 am	#1
oerg866 Retired Dormant Member Join Date: Jan 2014 Location: Frankfurt, Germany Posts: 4	Panasonic NV-FS90 Dead - but not quite Hi. My Panasonic NV-FS90 has had some problems. When I got it several months ago, it had the audio muting problem, which I fixed and then put the unit on a shelf because it has lots of those tiny white spot dropouts all over the image. I wanted to take a look at that today, but the unit is dead. When I plug in the power, the LED is on, the Display shows the volume meter (nothing else!!) And the head drum spins up with a very worrying noise (like an "eeeeehhhhhh"). So far I checked the power supply and found two bad capacitors (the 1µF 400V and one 100µF 50V). Could these be causing it? As far as I can see the 1µF cap would have caused the unit to be dead entirely, no? Cheers, Eric

14th Jan 2014, 11:16 pm	#2
vhs doctor Pentode Join Date: Oct 2011 Location: Athens, Greece. Posts: 173	Re: Panasonic NV-FS90 Dead - but not quite If the capacitors are responsible to supply the servo or the syscon circuits they can cause these problems it is better to recap all the PSU.

15th Jan 2014, 12:28 am	#3
Gillian Pentode Join Date: Jan 2014 Location: Portslade ,Brighton ,East Sussex Posts: 154	Re: Panasonic NV-FS90 Dead - but not quite I agree entirely with vhs doctor. When the electrolytics on the secondary were checked and removed there was an accompanying smell of electrolyte and leakage on the board. This job was quite an everyday occurance in the Panaasonic service centre I worked in. A lot of fault symptoms were caused by excessive hf ripple on supply lines.

15th Jan 2014, 9:39 am	#4
oerg866 Retired Dormant Member Join Date: Jan 2014 Location: Frankfurt, Germany Posts: 4	Re: Panasonic NV-FS90 Dead - but not quite Thanks for your replies, I will replace all the lytics on that PSU. Meanwhile got an NV-FS1 coming with less than 100 hours on it. That thing ought to work for sure, haha Cheers!