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-   -   Panasonic NV-HS950, cassette locked inside? (https://www.digitalfaq.com/forum/vcr-repair/10239-panasonic-nv-hs950.html)

promoter_2000 01-07-2020 03:14 PM

Panasonic NV-HS950, cassette locked inside?
 
Hello everyone. I have a problem with the Panasonic NV HS950 vtr: I inserted a cassette and the display reports error F04. Now I should remove the mechanics from the chassis but the cassette is stuck inside the housing and I can't get it out. To remove the mechanics I have to remove one last screw which is now covered by the locked cassette. If I don't take it off, there is no way to reach the damn fourth screw to unscrew it. I have the service manual of the NV HS950 and the K mechanics mounted on this appliance but I have not found any trace of how to remove a locked cassette without removing the mechanics. Please can someone help me by telling me how to do it? Thank you all. :depressed::depressed::depressed:

lordsmurf 01-08-2020 02:36 AM

It can be hard to remove cassettes, but generally, for almost all VCRs, safety gears/switches have to be moved in the correct positions, and then gears manually moved to eject the tape. It can wildly vary from model to model of VCR, even on the same brand. I deal with a lot of JVCs, and some JVCs are almost impossible, while others are almost obvious when you look at the deck innards.

Good luck!

josem84 01-08-2020 02:49 PM

Quote:

Originally Posted by promoter_2000 (Post 65630)
Hello everyone. I have a problem with the Panasonic NV HS950 vtr: I inserted a cassette and the display reports error F04. Now I should remove the mechanics from the chassis but the cassette is stuck inside the housing and I can't get it out. To remove the mechanics I have to remove one last screw which is now covered by the locked cassette. If I don't take it off, there is no way to reach the damn fourth screw to unscrew it. I have the service manual of the NV HS950 and the K mechanics mounted on this appliance but I have not found any trace of how to remove a locked cassette without removing the mechanics. Please can someone help me by telling me how to do it? Thank you all. :depressed::depressed::depressed:

Did you remove the front panel? Once you take off the big screws that hold the chasis in place, you just need to locate the loading motor and unthread the tape manually with the VCR shut down. Not as straightforward as other VCR's but easy.

Spend 5 more minutes to lubricate things as needed.

The F04 is in fact a code error for a cassette loading problem.

I have this one too in my collection... great VCR!!

latreche34 01-09-2020 12:45 AM

Did you try to back off the loading motor by hand with the power off by turning the worm gear screw until the cassette starts to rise and pull gently on the cassette while turning the screw until it come out.

dpalomaki 01-09-2020 10:32 AM

At least on the AG1980 the loading motor can also be powered by a battery to enable ejection of a stuck cassette, provided there is no serious binding in the mechanism. That is a lot faster than trying to spin the worm gear by hand (whcih takes forever and a day)

FWIW: the AG1980 service manual reads that a F04 error is caused by "Mechanism locks during tape unloading" and the remedy/check listed are "1. Check the loading motor circuit, and 2. Check the mechanism phase alignment."

https://www.tgrantphoto.com/sales/in...stuck-vhs-tape
might help.

The nylon worm gear coupling on the motor could split over time and slip causing load/unload failures. If the motor spins but it doesn't eject that could be the issue, it happened to mine. The tiny part is pricey but was still available on line year or two ago, if that is your issue.
https://www.ebay.com/itm/Motor-Pulle...-/133178913678
but you may find it cheaper if you look around.

promoter_2000 01-09-2020 02:55 PM

Thanks everyone for your help. Unfortunately I could not access the loading motor because the last of the four screws that fix the mechanics to the chassis was covered by the locked box. Even removing the bottom cover I would not have had access to the gears: the base of the chassis is completely closed by the plastic and also on it rests the main board on which the mechanics are inserted. An unsolvable problem with kindness. Now, however, I managed to remove the locked cassette: I removed the upper sheet metal cover of the loading compartment (fortunately fixed with stops), I folded up very gently, the two metal tabs that locked the cassette on the sides and finally I took it out by pulling it upwards. Then I brought the two tabs back to the horizontal position and unscrewed the last life left. Now the mechanics are out. I checked the loading motor but the nylon worm gear coupling is perfectly intact. The white worm wheel gear also has no broken teeth. But now I have the cassette loading compartment completely lowered, the two belt tensioning guides at the end of the stroke, the pinch roller completely lowered ... in short, the mechanics are still frozen in the reading position ... as if there was still a tape running inside. Error F04 always appears on the display. Now I don't know how to bring the loading slide back to its normal position (in practice bring it back like when you press "eject" letting out the cassette). Basically I solved the smaller problem but not the bigger one. :depressed:

latreche34 01-09-2020 03:11 PM

You need to reverse the loading motor to its eject position by turning it to the right direction when you see the tape P guides start to back off from the drum, keep turning until the tape compartment is completely up and the worm gear feels like it's at its dead end. If you don't feel comfortable doing the repair yourself just buy another VCR, it will cost you an arm and leg to have it repaired by a professional.

promoter_2000 01-09-2020 03:24 PM

Latreche34 very true. With what it cost me to buy it, I have no problem working on it alone ... I hope to succeed in the business.

josem84 01-09-2020 04:02 PM

Quote:

Originally Posted by promoter_2000 (Post 65695)
Thanks everyone for your help. Unfortunately I could not access the loading motor because the last of the four screws that fix the mechanics to the chassis was covered by the locked box. Even removing the bottom cover I would not have had access to the gears: the base of the chassis is completely closed by the plastic and also on it rests the main board on which the mechanics are inserted. An unsolvable problem with kindness. Now, however, I managed to remove the locked cassette: I removed the upper sheet metal cover of the loading compartment (fortunately fixed with stops), I folded up very gently, the two metal tabs that locked the cassette on the sides and finally I took it out by pulling it upwards. Then I brought the two tabs back to the horizontal position and unscrewed the last life left. Now the mechanics are out. I checked the loading motor but the nylon worm gear coupling is perfectly intact. The white worm wheel gear also has no broken teeth. But now I have the cassette loading compartment completely lowered, the two belt tensioning guides at the end of the stroke, the pinch roller completely lowered ... in short, the mechanics are still frozen in the reading position ... as if there was still a tape running inside. Error F04 always appears on the display. Now I don't know how to bring the loading slide back to its normal position (in practice bring it back like when you press "eject" letting out the cassette). Basically I solved the smaller problem but not the bigger one. :depressed:

As Latreche has already told you... just turn the worm gear, which is a small white gear. If you look at the loading motor, you can't miss it. Turn that wheel clockwise by hand and make sure to also turn manually the capstan motor to take up the tape. You don't want to damage the tape. Do it gently, let the mechanism do its thing. Don't apply any pressure.

Quote:

Originally Posted by dpalomaki (Post 65689)
At least on the AG1980 the loading motor can also be powered by a battery to enable ejection of a stuck cassette, provided there is no serious binding in the mechanism. That is a lot faster than trying to spin the worm gear by hand (whcih takes forever and a day)

Same with the 950, but it's better and safer to do it by hand. You can end up breaking things if the VCR hasn't been serviced in a while. It doesn't take too much, just a couple minutes.

Serco 11-29-2021 11:01 AM

@promoter_2000

I am a year or two behind. I am in the middle of this exact same problem. As you say its impossible to access the fourth screw with the cassette blocking access.

The third way is to undo the screw at the right hand side of the cassette carrier. This is just about accessible. I did this and the cassette was released. Though now I am stuck with trying to realign the tape carriage. And I still don't know if the loading motor is functioning as it should. I've moved from an 'F4' to an 'F6'.

By going into service mode '7' You can do this by holding the jog dial and pressing 'eject' until the display shows service mode '7'. I can then perform the LOAD function by pressing 'PLAY' and UNLOAD with 'STOP'. In both cases various wheels turn, but the cassette does not drop into place. I shall assume that the realignment will resolve this.

I'd be interested in your experience. Did you continue with your attempts at fixing it? Thanks

promoter_2000 12-04-2021 12:56 AM

Yes, I continued by finding some broken plastic gears (the whorm gear with a broken tooth and a broken brake) and I tried to replace them by buying the spare parts in Australia (I live in Europe!) Luckily for very little price but ... not it did no good. The mechanics were misaligned and had to be completely disassembled and reassembled. Not finding more technicians able to do it and, above all, to limit the waste of money, I decided to stop and wait for the auction of a 950 sold as "spare parts". In the end I found it, I used only the mechanics (in good condition) and now my NV HS950 works perfectly. I hope I was helpful.

latreche34 12-04-2021 11:48 AM

Glad you finally got it to work. Yah, qualified technicians that work on these things are fewer and far in between and test equipements and tools are hard to find and out of calibration so the only way to get these ancient beasts to keep going is to swap out parts from another aging but still working units unfortunatly. I don't hope for newer machines with capturing capabilities to be made as some may claim, there is no financial feasability for such a project.

hodgey 12-04-2021 04:21 PM

Just a heads up that if you are in Europe there are cheaper decks with the same mechanism. Panasonic use the K-mechanism in consumer decks ( PAL NV-SD, NV-HD and NV-HS models) in Europe between about 1993 and up to and including 1996. There are two main variants of the mech as it was used in both side mounted (e.g nv-hd100, nv-hs1000) and mid-mounted (e.g NV-HS950, NV-HD610, NV-SD300) ones and thuse have some differences with the pcbs under them and I think a screw hole not present on all. The last non-SVHS like the HD620, SD220 use a different head amplifier mount as they have a newer style head drum with motor on top but should otherwise share parts. Note that the multi-system variants have slightly inconsistent naming, the multi-system 620 is newer than the PAL 620 and uses the Z mech. Always check with service manual if possible, they state [K-MECHANISM] on the cover page if it uses it.

Additionally, there are some AG series models (not the big bertha broadcast ones) that use it both in Europe and US that use it i.e AG5260, AG1980 of course, and a few others.

promoter_2000 12-05-2021 08:42 AM

I confirm! In fact, it is absolutely essential that the replacement mechanics be "K" and not others.


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