Panasonic NV-F70 Mech Problem - UK Vintage Radio Repair and Restoration Discussion Forum

Ceemac66 · 19th May 2018, 8:43 am

Hi all, hoping for some direction.
I bought the Panasonic NV-F70 Video Recorder around '88/89 and enjoyed it for a couple of years.
I got a brand new Midnight Express video in the early 90's and when I put the cassette in the machine, I got all kinds of crunching and rattling from the deck.
I had to dismantle the unit to remove the non working cassette, which promptly went into the bin!
And that was the end of my NV-F70....
I tried to diagnose the issue, of course the belts had all slipped and I think a cog or two now had missing teeth but I could not get it to work properly.
I have used it a couple of times recently for transferring video to digital but I have to manually load the cassette with no power to the machine.

Does anyone know if or how I can fix it after all this time?
And by the way, I still haven't forgiven Midnight Express and to this date, have not seen it!

Many thanks
Chris

mark2collection · 19th May 2018, 9:46 am

Ahhh, the Panasonic G-Mech Rev II 'turbo' ...

The cause back in the day used to be, the cassette housing side-plate would lose a lug & slip a tooth or three (small metal gear just under the cassette housing), & if the capstans' rotor clutch was maladjusted (too tight) the machine would thunder on & strip more gears.

I'll try & dig out my old documents on these mechs & scan in, though that won't be until next week (no scanner here at home!)

The G-Mech needs to be aligned in the half-loaded position, i.e., cassette housing in, P5 selector arms laced, main rotor free moving. Don't worry, the document I have is a Panasonic original & will explain all ...

Great machines, seen lots of 'em, I still have my NV-F55 plus an NV-FS90 ... having worked for Panasonic AV service department back in the early '90's (25% staff discount back then) ... If you're lucky, I may well still have some new/unused mech parts too ... Including some gears! (I really need to sift through my workshop).

G & J series were entry models, F series mid & FS series were, well Flag-Ship ... hence, FS ...

Once the mech is aligned & operated with care (customers used to 'shove' the cassette in, rather than 'let' the machine 'take' the tape. The hearty 'shove' would wreck the cassette housing lug & cause not end of grief) they're great machines ...

Mark

dj_fivos_sak · 19th May 2018, 11:55 am

The G/G2 mechanism is a real pain to re-time/re-align. These videos should help you out although they are the G1 revision.
https://www.youtube.com/watch?v=eErlcvfD_Ds&t=154s
https://www.youtube.com/watch?v=Yf9deOEVwLk&t=150s
If you need the service manual:
http://freeservicemanuals.info/en/se...nasonic/NVF70/
Also don't forget to clean the mode switch. These things cause lots of issues.

Fivos

radioman · 19th May 2018, 2:08 pm

I can commiserate with you Chris, as this sounds exactly like what happened to my NV-F65... and I've not got round to looking at mine either, in fact I think it's still got the new blank cassette in it !
Can the experts tell me if this has the same mechanism and therefore the same solution ?

Andy

dj_fivos_sak · 19th May 2018, 3:07 pm

According to the manual, the F70 has the G1 mechanism. So the F65 should be no different My FS200 is a G2 deck.

Fivos

Mike Fulton · 23rd May 2018, 9:21 pm

I always have been and still am, employed in a Panasonic Serice Centre.

What you really need is a G Mech VUA4116KIT repair kit but although I have mode switches galore I don't have the kit or parts thereof.
If you can source a good condition G Mech for the parts with damaged teeth I can rebuild your set and fit a new mode switch but it would mean some arranging as I'm near Durham....

interocitor · 24th May 2018, 8:28 am

I think the manual for some G decks showed the side plate relationship with the metal chassis gear in the wrong position for "half load" cassette in and down, please beware !!

Welsh Anorak · 24th May 2018, 2:43 pm

I quite liked the G-deck, but I found when fitted to a Philips machine they always seemed to lose their timing. Some of the parts seemed different to the Panasonic - and cost a lot more!
As customers aren't renowned for their care and patience, whenever we'd replaced gears, mode switch, the carriage RHS and re-timed a G-deck I'd push in the empty carriage by hand. Hopefully there would be a hiss from the clutch, a moment of silence and the tray would then eject. Bit brutal, I know, but better than an irate customer!

Ceemac66 · 1st Jun 2018, 3:56 pm

That would be great Mark. Any docs would help, I guess.

Great videos, Fivos. Annoyed I didn't find these myself but I guess it helps knowing it is a G-Deck!

Hi Mike, I'm pretty sure its only the teeth on mine that are bodgered!
I may even be so bold to suggest it is just timing that is the problem because when I load a cassette manually, with no power, I get it so far and then apply power, the mechanism takes the cassette and plays no problem. It also ejects with no issues... It just doesn't like the initial automatic loading.
I will have a go at the timing and see what happens. And thanks for your offer, I'm not too far away.

Chris

Mike Fulton · 1st Jun 2018, 9:21 pm

There's a VUA4116KIT up for grabs on this forum!

Ceemac66 · 6th Jun 2018, 6:48 am

Quote:

Originally Posted by mark2collection

Ahhh, the Panasonic G-Mech Rev II 'turbo' ...

The cause back in the day used to be, the cassette housing side-plate would lose a lug & slip a tooth or three (small metal gear just under the cassette housing), & if the capstans' rotor clutch was maladjusted (too tight) the machine would thunder on & strip more gears.

I'll try & dig out my old documents on these mechs & scan in, though that won't be until next week (no scanner here at home!)

The G-Mech needs to be aligned in the half-loaded position, i.e., cassette housing in, P5 selector arms laced, main rotor free moving. Don't worry, the document I have is a Panasonic original & will explain all ...

Great machines, seen lots of 'em, I still have my NV-F55 plus an NV-FS90 ... having worked for Panasonic AV service department back in the early '90's (25% staff discount back then) ... If you're lucky, I may well still have some new/unused mech parts too ... Including some gears! (I really need to sift through my workshop).

G & J series were entry models, F series mid & FS series were, well Flag-Ship ... hence, FS ...

Once the mech is aligned & operated with care (customers used to 'shove' the cassette in, rather than 'let' the machine 'take' the tape. The hearty 'shove' would wreck the cassette housing lug & cause not end of grief) they're great machines ...

Mark

Hi Mark, Did you get anywhere scanning those documents in?
I saw the kit too but I guess its already gone?

Cheers
Chris

19th May 2018, 8:43 am	#1
Ceemac66 Retired Dormant Member Join Date: May 2018 Location: York, North Yorkshire, UK. Posts: 3	Panasonic NV-F70 Mech Problem Hi all, hoping for some direction. I bought the Panasonic NV-F70 Video Recorder around '88/89 and enjoyed it for a couple of years. I got a brand new Midnight Express video in the early 90's and when I put the cassette in the machine, I got all kinds of crunching and rattling from the deck. I had to dismantle the unit to remove the non working cassette, which promptly went into the bin! And that was the end of my NV-F70.... I tried to diagnose the issue, of course the belts had all slipped and I think a cog or two now had missing teeth but I could not get it to work properly. I have used it a couple of times recently for transferring video to digital but I have to manually load the cassette with no power to the machine. Does anyone know if or how I can fix it after all this time? And by the way, I still haven't forgiven Midnight Express and to this date, have not seen it! Many thanks Chris

19th May 2018, 9:46 am	#2
mark2collection Hexode Join Date: Jul 2010 Location: Royal Berkshire, UK. Posts: 471	Re: Panasonic NV-F70 Mech Problem Ahhh, the Panasonic G-Mech Rev II 'turbo' ... The cause back in the day used to be, the cassette housing side-plate would lose a lug & slip a tooth or three (small metal gear just under the cassette housing), & if the capstans' rotor clutch was maladjusted (too tight) the machine would thunder on & strip more gears. I'll try & dig out my old documents on these mechs & scan in, though that won't be until next week (no scanner here at home!) The G-Mech needs to be aligned in the half-loaded position, i.e., cassette housing in, P5 selector arms laced, main rotor free moving. Don't worry, the document I have is a Panasonic original & will explain all ... Great machines, seen lots of 'em, I still have my NV-F55 plus an NV-FS90 ... having worked for Panasonic AV service department back in the early '90's (25% staff discount back then) ... If you're lucky, I may well still have some new/unused mech parts too ... Including some gears! (I really need to sift through my workshop). G & J series were entry models, F series mid & FS series were, well Flag-Ship ... hence, FS ... Once the mech is aligned & operated with care (customers used to 'shove' the cassette in, rather than 'let' the machine 'take' the tape. The hearty 'shove' would wreck the cassette housing lug & cause not end of grief) they're great machines ... Mark Last edited by mark2collection; 19th May 2018 at 9:57 am. Reason: More detail/spelling

19th May 2018, 11:55 am	#3
dj_fivos_sak Heptode Join Date: Mar 2015 Location: Lefkada, Greece Posts: 969	Re: Panasonic NV-F70 Mech Problem The G/G2 mechanism is a real pain to re-time/re-align. These videos should help you out although they are the G1 revision. https://www.youtube.com/watch?v=eErlcvfD_Ds&t=154s https://www.youtube.com/watch?v=Yf9deOEVwLk&t=150s If you need the service manual: http://freeservicemanuals.info/en/se...nasonic/NVF70/ Also don't forget to clean the mode switch. These things cause lots of issues. Fivos

19th May 2018, 2:08 pm	#4
radioman Heptode Join Date: Apr 2003 Location: Ayr, Ayrshire, UK. Posts: 631	Re: Panasonic NV-F70 Mech Problem I can commiserate with you Chris, as this sounds exactly like what happened to my NV-F65... and I've not got round to looking at mine either, in fact I think it's still got the new blank cassette in it ! Can the experts tell me if this has the same mechanism and therefore the same solution ? Andy

19th May 2018, 3:07 pm	#5
dj_fivos_sak Heptode Join Date: Mar 2015 Location: Lefkada, Greece Posts: 969	Re: Panasonic NV-F70 Mech Problem According to the manual, the F70 has the G1 mechanism. So the F65 should be no different My FS200 is a G2 deck. Fivos

23rd May 2018, 9:21 pm	#6
Mike Fulton Pentode Join Date: Apr 2006 Location: 7 Miles North of Durham, UK. Posts: 130	Re: Panasonic NV-F70 Mech Problem I always have been and still am, employed in a Panasonic Serice Centre. What you really need is a G Mech VUA4116KIT repair kit but although I have mode switches galore I don't have the kit or parts thereof. If you can source a good condition G Mech for the parts with damaged teeth I can rebuild your set and fit a new mode switch but it would mean some arranging as I'm near Durham....

24th May 2018, 8:28 am	#7
interocitor Diode Join Date: Aug 2010 Location: Dundee, Scotland, UK. Posts: 3	Re: Panasonic NV-F70 Mech Problem I think the manual for some G decks showed the side plate relationship with the metal chassis gear in the wrong position for "half load" cassette in and down, please beware !!

24th May 2018, 2:43 pm	#8
Welsh Anorak Dekatron Join Date: Apr 2005 Location: North Wales, UK. Posts: 6,918	Re: Panasonic NV-F70 Mech Problem I quite liked the G-deck, but I found when fitted to a Philips machine they always seemed to lose their timing. Some of the parts seemed different to the Panasonic - and cost a lot more! As customers aren't renowned for their care and patience, whenever we'd replaced gears, mode switch, the carriage RHS and re-timed a G-deck I'd push in the empty carriage by hand. Hopefully there would be a hiss from the clutch, a moment of silence and the tray would then eject. Bit brutal, I know, but better than an irate customer! __________________ Glyn www.gdelectronics.wales

1st Jun 2018, 3:56 pm	#9
Ceemac66 Retired Dormant Member Join Date: May 2018 Location: York, North Yorkshire, UK. Posts: 3	Re: Panasonic NV-F70 Mech Problem That would be great Mark. Any docs would help, I guess. Great videos, Fivos. Annoyed I didn't find these myself but I guess it helps knowing it is a G-Deck! Hi Mike, I'm pretty sure its only the teeth on mine that are bodgered! I may even be so bold to suggest it is just timing that is the problem because when I load a cassette manually, with no power, I get it so far and then apply power, the mechanism takes the cassette and plays no problem. It also ejects with no issues... It just doesn't like the initial automatic loading. I will have a go at the timing and see what happens. And thanks for your offer, I'm not too far away. Chris

1st Jun 2018, 9:21 pm	#10
Mike Fulton Pentode Join Date: Apr 2006 Location: 7 Miles North of Durham, UK. Posts: 130	Re: Panasonic NV-F70 Mech Problem There's a VUA4116KIT up for grabs on this forum!