Panasonic S-VHS booting fault, can we fix it? Too stupid. AG-4700/NV-HS1000.

[@crashbandicoot4everr]

That drum motor sounds like a Seagate SCSI hard drive from the early 90s lol. I would try swapping the mode encoder switch over as these are known for causing weird faults.

[@timf-tinkering]

Can't see how that fault would be mode-switch related. Symptoms definitely point to a capacitor problem - somewhere!

[@crashbandicoot4everr]

@@timf-tinkering Sure, but what if there's an intermittent connection inside the contacts?

[@TigerBoyRS]

Damn, that video head drum... Not only did it become an "air-raid" siren like Max said, but it also cracks some laughs back at you, when finally winding down. Just like in a twisted plot. Please don't question yourself that hard Colin, it's only that those machines were troublesome divas, new from factory. Now they are old news, but still sense the use and help on savaging vintage video footage, so they keep pushing on that cocky attitude. Playing tricks and fooling around... Allways in need to be cherished and pampered. Over engineering at its worst. Cheers from 🇵🇹

[@alphabeets]

Since the head is spinning at a crazy speed it would seem to be related to a servo circuit not sensing the head speed. Is there a sensor for that to check?

[@avtransfersUK]

Ive got a few similar machines. Weird faults and as they say “not economical to repair”. Nice video and good to know that these machines can keep us guessing. I hope you figure it out. 👍

[@Petertronic]

Weird one! I wonder what RPM that drum is doing, sounds like 10x normal at least. Mode switch (that others have mentioned) might be an idea. Or maybe the humidity/dew sensor? Does it ramp up the drum to help it 'dry' it if it thinks it has condensation? I'm itching to know what it is!

[@alyro-ls1dv]

how about the board with the buttons in the front door? I know it sounds unlikely but the communication to these is shure logic not electric only and the opening is putting stress on the wiring and moreover there might be capacitors along with the switches, too. By the way, you are for shure not stupid and I admire the time and passion you spend in sharing your thoughts and practice on repair of great tech from yesteryear and it might even help the community to keep some of these in working condition. The effort companies like panasonic invested in this gear and the experience grown over decades to deliver such good homevideo equipment is now all lost to the ever growing digital convergence. But this is great admireable technology and repairing it is one of the best ways to show respect for the wonderful engineering invested in developing and producing these machines. Thank you and well done (even better if you get this bloody thing back to normal performance as you have shown it the brother already being in an even poorer state awaiting nothing better than the bin after the connectors are missing and the processor board seems broken and the drum is worn out). Best Albrecht

[@yellowcrescent]

The SVHS light blinking is weird, and at the end it also coincides with the drum revving up again. Maybe there is a common connector/path/board that both of them share (from wherever SVHS is being detected) that might point in the direction of the fault?

[@Televid4]

HI, I have done this type of fault back in the 90s on a NV-HD610 were the cassette was stuck inside the machine and the drum was running at excessive speed with the error code 09. I had replaced a 6mhz crystal (X6001). I also remember some Panasonic VCRs back in the days that had to be modified. Panasonic and Bang and Olufsen were well know for modification and kits were supplied by them. Try checking the crystal on the front display. I think when you replaced the board from the scrap machine it did not work because it maybe slightly different. Check the machines original board and mainly the crystal(s). Good Luck...

[@moritzeheim132]

I had an NV-HD700 (or HS900??) with similar behaviour. It was due to a connection to the front panel. Maybe it helps to check the ribbon cables?

[@analogvideochannel4612]

Another bit you could try swapping is the power transistor that is screwed onto to the mechanism (they used it as a heatsink). There is also a pcb under the mechanism but not sure if it has any components or if it's just connectors. Lastly TBC module if you didn't try that already but that seems ver very unlikely.

[@video99couk]

TBC would be crazy. But then this fault is crazy. So if there was a bus communication problem, it's not impossible.

[@basroos_snafu]

Is there any circuit in there that has a time out that matches the time it takes the unit to come in the normal operational state? The blinking S-VHS LED made me think about a possible sensor related error, it may be trying to determine something it can't resolve and just continue afterwards.

[@vhssnippets1799]

Possibly a bad connection in the wiring loom/dry joint on a PCB/dirty switch contact to a logic input. The floating input could be causing the processor to see a particular logic state on power up which somehow controls the drum motor speed. Over a period of a few tens of seconds the logic may flip state and then remain in the new state until the power is sequenced again.

[@ChasLarge]

Did you swap the drop down keyboard? That is part of the "COMMS" as it uses the strobing to assess key presses, maybe liquid spillage in it? Have had that cause issues on similar bits of kit.

[@video99couk]

No because the scrap machine drop down section is in a terrible state. There's been no liquid spillage, at least not in the several years I've owned and used the machine.

[@janchristensen9858]

Have you clean the timing control ?

[@OAK77uk]

Well you certainly have patience - sometimes one has to let go into the hands of destiny - now about S-VHS I need to get a reliable unit for some early family vids - any that you might recommend? Thanks for posting - so happy to have found your channel.

[@5Breaker]

How many flex cables are in there that you would have to check?

[@swilwerth]

Does it changes something if you shake it during fault? Could be a cold solder joint on the signal path of the hall sensor that tells the speed of the drum to the servo controller. Or it could be an undocumented 'feature'.

[@AVadim]

Hello! Who have Owner's Manual in PDF for this VCR? Service Manual I have.

[@video99couk]

The service manual for the NV-HS1000 is readily available and will cover about 99% of this machine. Try elektrotanya.com

[@AVadim]

@@video99couk Thank you!

[@Steveuk405]

What board is the microprocessor on? And that bottom board does what exactly ?

[@stanislavnepochatov8381]

Yes, Max, it totally does sound like air raid siren. I can verify that. And I hope you will never hear it in real life.

[@araara-l9h]

What is the main difference between hs1000 and ag-4700?

[@video99couk]

The main difference is the cabinet colour! Other differences: Different remote control (though they are interchangeable), frame accurate editing is an optional extra on the NV-HS1000 and included on the AG-4700. That's probably it. But for some reason, I think the AG-4700 might give slightly better pictures.

[@araara-l9h]

@@video99couk Thank you

[@letmelooktv]

I still have a bunch of old video kit including one machine and the edit controller from an ag 5700? series. I kept hold of it meaning to do some transfers one day. The other one got stolen out of the boot of my car. Have you in mind to pass the bits on to when i've got around to it & some old random capture kit as well. Cos i really enjoy your content.

[@Capturing-Memories]

What if you build a machine from scratches based on a scrap one that didn't have this problem and put all the working parts except the ones that are on the faulty machine such as cables, key pad panel, machanism ...etc, and see how it goes.

[@artyrgriboedov4520]

Здравствуйте,надо поменять плату сервопривода,Я думаю проблема там vep02389

[@JohnCarlson-kk2bj]

I have almost the same problem in my NV-HS1000 right now, except it will not stop spinning. I have read online that another person had the same issue and it was bad caps in the PSU, i will change all mine and see. I saw in an earlier episode that you switched the PSU but have you checked the Caps in that PSU?

[@video99couk]

Agreed, I've not checked the replacement. However I've had a number of HS-1000 and AG4700 machines and never had this problem before. I think the odds of the same very unusual fault on both PSUs is very small.

[@JohnCarlson-kk2bj]

@@video99couk Ok, yes maybe. In my machine i think itcould be the PSU because i put the NV-HS1000 in storage many years ago when it got an loading issue with the cassette. but everything else was working fine, and now after so many years this error! the Caps would be my first guess. Thanks for your videos that was the reason i am now took out my old HS1000 and is trying to fix it.

[@JohnCarlson-kk2bj]

Hello again, i finally got arround to change all caps in the PSU. And yes no more jet engine noice 🙂 now its time to see if the small coupler mechanism has broken because loding is still not working properly @@video99couk

[@jameslaidler2152]

A sunny day? In the UK? Surely not!

[@video99couk]

We live in Sunny Devon!

[@zx8401ztv]

What a mad fault, there is a cable from the motor to the servo control, are the connectors ok and no chafing of the harness wires insulation and grounding a control wire. Its very odd lol.

[@artyrgriboedov4520]

Здравствуйте,2 часть будет?

[@video99couk]

This is part 2! There will be a part 3. I am going to go through a power supply, replacing any bad capacitors, and try it again.

[@ZXByteman]

There is a common problem related to Cap on 5V power rail inside PSU. Replacing this cap usually brings these AG4700/HS800/1000 back to life. Please check that cap.

[@video99couk]

I will be working on the PSU shortly.

[@stephan.scharf]

I think Max is right. Or not? I admire your patience.

[@fluxjunkie6645]

I have strange faults on these machines and its been an intermittent mode switch it seems they can cause very strange faults sometimes.also check the opto sensors

[@plesio2830]

you didn't check power suply and mode switch

[@video99couk]

I swapped the power supply from another machine. The fault is not the mode switch, symptoms don't line up at all.

[@frankgriese7213]

I had a totally different machine recently that was in same spinning up symtom. That unit went litterally into smoke as the PS exploded

[@NikHYTWP]

Wow that's a fast spinning motor. On my JVC HM-DR10000 one of the motors spins up with no tape in the mechanism exactly like that after a loss of power (but nowhere near as fast). It's only fixed if push in a tape as I turn the power on in which case the VCR takes it and then never does the thing again even if you power it off as long as it's plugged into the wall. I figure it must be the mode switch being dirty but that requires a lot of disassembly on that model so I'm just sticking with my solution.

[@andydredlox8686]

Possible same capacitor fault in both PSUs and only affects that model and runs perfectly in other models...i.e. that model needs more amperage at start up than the model the replacement PSU came out of?? I'm no expert but just a suggestion

[@alyro-ls1dv]

this would be my first thought, too

[@DK640OBrianYT]

Sold off my consumer equivalent NV-HS1000 years ago, at least a decade by now. It was faulty then, having this weird jet enginge sound. And that was after having been to the repair shop twice haivng trouble ith "the mode switch". But if I remember correctly, they said it was the VHS/S-VHS-switch. Your S-VHS light is flashing...maybe there's a short..... Loved the picture though, when it was working. It recorded and played sharp and crisp, but my late 80's JVC HR-S5000 outlived this Panasonic with lightyears. Didn't want to mess further with this fragile machine.

[@eneaauriti]

Replacement of a lot of components is a good thing because it could be anything

[@TTVEaGMXde]

Front PCB left has as possible sources of error C 6508 (16V33) short circuit of REG 12.3V (for mic amp) and C 6510 (6V47) power supply for IR receiver via 47 ohm series resistor, which can lead to interference for the controller. My satellite receiver (TF5000MP) sometimes gets stuck when the batteries are running low. TBC has no connection to the data bus. If you move it several times and make the same mistake, damage to the cable is rather unlikely.

[@speed_rider362]

At least the vcr somewhat works. I own the NV-HS1000 but seldom use it. I like my NV-HS950 much more. Almost the same features but much simpler to repair.

[@video99couk]

Strangely I prefer the AG-4700 and rarely use my NV-HS950. The pictures just seem cleaner on the AG-4700. Maybe my 950 is less than perfect.

[@voceyc]

Hmm….. could it be a cable shorting when the machine starts up? Could the short be activated by any moving parts? How annoying! I hope you find the fault

[@digitalz1988]

As the fault clears, its sounds like its still trying to pulsing to high speed, but I can hear anything else on the deck moving? i.e. that doesn't sound consistent with a mode switch, mechanical fault (dry joint / connector) unless its warming up? So its got to be something electrical and improving with heat or charge?? (wondering what happens if you quickly flick the power off/on). From other comments, this doesn't sound totally isolated so maybe its just 2 duff supplies. Sorry thinking aloud here rather than providing anything useful :)

[@rolfkleiber9178]

Have you ever fixed it?

[@video99couk]

No, it's been put to one side. If I get another similar machine in, I'll do some more fault finding.

[@rolfkleiber9178]

​@@video99couk I organized a elektronical working device. I swapped the PSU, wich solved the problem of the spinning head. So I guess recap is needed.

[@t0nito]

Well, you basically swapped the whole system except the mechanism itself, so I would point to there, either a dirty mode switch, or some sensor.

[@video99couk]

Don't see it being a mode switch as it recovers consistently. But perhaps something else in the deck, or a comms fault caused by something weird like the TBC.

[@henriksommer3844]

Check the modeswitch…

[@video99couk]

I'm really not getting mode switch vibes from this fault.

[@dragonlard4595]

Study the Service Manual? If available.....

[@video99couk]

You will see I've been using the service manual. But it doesn't go into huge detail about the firmware and what exactly will trigger an E9 error.

[@mkdsuser]

I do wonder if its a power fault - The drum spins at high speed so as to draw as much power as possible, this then maybe charges a capacitor or some other component that once 'charged' is able to operate properly which is why it seems (from what i can see in your video anyway) to operate fine until you unplug it and re-plug it in. The £9 error may just be a coincidence, perhaps due to that same power fault a component isnt sending an 'OK' signal to the rest of the deck when its expected, the system times out and goes into a waiting state. Then when the power fault resolves itself the system bascally goes 'Ok all good now' , the head drum then slows down as thats not normal operating speed anyway and the unit goes into normal service condition. - All purely guesswork!

[@Vintaginside]

I would fully recap the PSU and see if this makes a change. If still failing, have a look at heads tacho signals (FG/PG) just in the servo chip input pins. Not an easy repair, don't blame yourself.

[@dannyjaar]

that headspin is a normal thing

[@rsuryase]

My guess is a bad transistor.

[@skyoreece9805]

I'd would think its a psu fault

[@video99couk]

That's where I started, it certainly feels like a PSU fault.

[@bobsbits5357]

hi done so many change over parts yes to betacam decks i come to to end of doing this i have run out of decks i can get parts from and the lady that help me on the money side the price of used video's are going silly now re cap of reel to reel i have to do as costs are ok you done video on the keeping decks going i will say adat recorders are good for the money

[@wendyherssens2292]

Suspect power supply just replacing with one from scrap machine is not the way to go, I would replace the caps in the power supply. I always do with all my Panasonic video's with positief result even beter playback quality.

[@video99couk]

It is my plan to do a capacitor refit on the power supply that came out of this machine. But I really don't think it's the cause of the fault.

[@artyrgriboedov4520]

Ошибся номером vep02412

[@chikorolls3951]

Try replacing 2SB841 that is mounted on the back RHS of the mechanism (looking from the top). Has a blue 3 pin plug.

[@chikorolls3951]

Sorry it's a 2SB941 NPN not 841. It is on the other end of the cable socket that you broke in a previous video!

[@chikorolls3951]

This fixed an identical fault for me on a NV-HS1000

[@chikorolls3951]

Sorry, ignore the above it was power supply caps afterall!