Panasonic NV-FS100B S-VHS VCR - dead - PSU? - UK Vintage Radio Repair and Restoration Discussion Forum

NST · 18th Aug 2006, 2:44 pm

Hi, got given an old (kind of vintage!) Panasonic S-VHS deck a few months ago, the problem is, it died after going a bit mad! I couldn't eject a tape as the front panel controls stopped responding (the switches worked OK), and the tuner wouldn't tune in. Also the power LED seemed a bit dim before it went as well, then it wouldn't power up (a single 'chirp' could be heard from the PSU).

I decided to take out all the electrolytics in the PSU, and replaced them all with some nice new Panasonic ones. This didn't solve things as the 'chirp' could still be heard when the PSU was connected to the motherboard. If disconnected, the PSU would start, and voltages were present at PSU edge connector. I now suspect one of the Zener diodes is at fault - am i correct? I only have a multimeter to carry out tests, and i'm unsure about which diode to replace. Also, someone told me that the diodes have been discontinued for this model - could anyone recommend any alternatives? I wish to replace as many of them as possible for better reliability. Here's the part numbers for most of the main ones in the PSU:

EM1BLF x4
VSD0002 x1
AP01C x1
MA4030L x1
MA178 x1
MA165 x1
ERA22-02 x1
FMLG12SP x1
FMBG14L x1
10ELS2 x1
EK14LF x1
MA2160A
MA4130L x1

Any help with equivilants, or where to find the originals, will be most appreciated.

Andy

Nickthedentist · 18th Aug 2006, 3:13 pm

Andy,

Blanket replacement of caps in this kind of thing is an excellent idea

But after that, you really need to use your head and a circuit diagram. Changing all the other components would be expensive and time consuming, and still may not solve the problem.

You can get a free service manual for the NV-FS88 here, which may be similar in many respects to your machine: http://www.eserviceinfo.com/index.php?what=search

The other thing to check when odd mechanical problems arise is the MODE SWITCH - the bit on the deck that tells the microprocsessor what position the deck's in e.g. winding, playing, searching, half way in between modes, etc.

Nick.

NST · 18th Aug 2006, 7:03 pm

Hi Nick, thanks for your fast reply. I have the service manual for the FS100, but only very basic test equipment. I'm suspecting AP01C, and ERA22-02 (equiv: PQVDERA22-02), but i'm having difficulty locating a good UK based supplier for these diodes.

Nickthedentist · 18th Aug 2006, 7:08 pm

For semiconductors, try ringing these people:

http://www.dalbani.co.uk/

or

http://www.grandata.co.uk/

or

http://www.wiltsgrove.co.uk/

And post the power supply diagram here so that the clever members of the forum (not me) can make some suggestions.

Nick

NST · 19th Aug 2006, 3:39 pm

I've attached a photograph of the PSU schematic (no scanner unfortunately) the quality ain't great, but still viewable. Here are the corresponding reference numbers for each diode:

D1102 to D1105 = EM1BLF (x4)
D1106 = VSD0002
D1107 = AP01C
D1108 = MA4030L
D1109 = MA178
D1110 = MA165
D1111 = ERA22-02
D1112 = FMLG12SP
D1113 = 10ELS2
D1114 = FMBG14L
D1115 = EK14LF
D1116 = MA2160A
D1117 = MA4130L

I will try and contact some of those suppliers hopefully this week as well.

Andy

18th Aug 2006, 2:44 pm	#1
NST Retired Dormant Member Join Date: Aug 2006 Location: North Bedfordshire Posts: 7	Panasonic NV-FS100B S-VHS VCR - dead - PSU? Hi, got given an old (kind of vintage!) Panasonic S-VHS deck a few months ago, the problem is, it died after going a bit mad! I couldn't eject a tape as the front panel controls stopped responding (the switches worked OK), and the tuner wouldn't tune in. Also the power LED seemed a bit dim before it went as well, then it wouldn't power up (a single 'chirp' could be heard from the PSU). I decided to take out all the electrolytics in the PSU, and replaced them all with some nice new Panasonic ones. This didn't solve things as the 'chirp' could still be heard when the PSU was connected to the motherboard. If disconnected, the PSU would start, and voltages were present at PSU edge connector. I now suspect one of the Zener diodes is at fault - am i correct? I only have a multimeter to carry out tests, and i'm unsure about which diode to replace. Also, someone told me that the diodes have been discontinued for this model - could anyone recommend any alternatives? I wish to replace as many of them as possible for better reliability. Here's the part numbers for most of the main ones in the PSU: EM1BLF x4 VSD0002 x1 AP01C x1 MA4030L x1 MA178 x1 MA165 x1 ERA22-02 x1 FMLG12SP x1 FMBG14L x1 10ELS2 x1 EK14LF x1 MA2160A MA4130L x1 Any help with equivilants, or where to find the originals, will be most appreciated. Andy

18th Aug 2006, 3:13 pm	#2
Nickthedentist Dekatron Join Date: Jan 2005 Location: Oxford, UK. Posts: 17,846	Re: Panasonic NV-FS100B S-VHS VCR Andy, Blanket replacement of caps in this kind of thing is an excellent idea But after that, you really need to use your head and a circuit diagram. Changing all the other components would be expensive and time consuming, and still may not solve the problem. You can get a free service manual for the NV-FS88 here, which may be similar in many respects to your machine: http://www.eserviceinfo.com/index.php?what=search The other thing to check when odd mechanical problems arise is the MODE SWITCH - the bit on the deck that tells the microprocsessor what position the deck's in e.g. winding, playing, searching, half way in between modes, etc. Nick.

18th Aug 2006, 7:03 pm	#3
NST Retired Dormant Member Join Date: Aug 2006 Location: North Bedfordshire Posts: 7	Re: Panasonic NV-FS100B S-VHS VCR Hi Nick, thanks for your fast reply. I have the service manual for the FS100, but only very basic test equipment. I'm suspecting AP01C, and ERA22-02 (equiv: PQVDERA22-02), but i'm having difficulty locating a good UK based supplier for these diodes.

18th Aug 2006, 7:08 pm	#4
Nickthedentist Dekatron Join Date: Jan 2005 Location: Oxford, UK. Posts: 17,846	Re: Panasonic NV-FS100B S-VHS VCR For semiconductors, try ringing these people: http://www.dalbani.co.uk/ or http://www.grandata.co.uk/ or http://www.wiltsgrove.co.uk/ And post the power supply diagram here so that the clever members of the forum (not me) can make some suggestions. Nick