Look at Panasonic AG-4700 and JVC HR-S7600 SVHS with TBC. I'm upset now.
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- Опубліковано 31 лип 2024
- Two SVHS machines get looked at today, a AG-4700 with a slight problem at power-up, and test a JVC HR-S7600. Both of these machines include a Digital Timebase Corrector (TBC) which is very useful for getting the best results with tape transfers. Finally a quick chat about why I am upset.
Since recording this video, there's been a development: The AG-4700 displayed E9 during the fault condition, which means Serial Clock Transmission Error between the front panel CPU IC7501 and syscon IC6001. So the fault may lie in the front panel, which could be relatively easy to change.
Audio and video transfers: www.video99.co.uk/
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Music “Let It Run” with permission, copyright Cristie/MacFarlane.
Sorry I do not offer an audio or video equipment repair service.
00:00 Introduction
00:37 Work on Panasonic AG-4700 fault
04:37 Main panel swap
11:47 Stop work and clean
14:00 JVC HR-S7600
22:09 Conclusion, I've been upset - Наука та технологія
Having just bought a job lot of five AG-4700s, I'm finding your channel invaluable reassurance and guidance. I've been lucky - four out of my five decks appear to work pretty well, after a good head clean with isopropyl. One spits tapes back out after making a remarkable rattling sound - still trying to work that out! But I could see myself doing some component swaps to create sellable machines in the weeks and months ahead, in a bid to recoup some of my outlay - and your channel is the only one really talking about this model. So I'm doubly lucky that you do it in such a calm and detailed fashion. Thank you, and keep up the good work.
Yep some people can be selfish and expect too much.
Colin, you do a dam good job of recovering peoples crappy recordings.
I'm not sure about the AG machine, it did sound like under then over compensation.
I would make sure the head drum can be rotated really easy by hand and no drag.
Servo capacitors may not be helping.
Don't forget that even the main pcb you put in may also have halfbaked crapacitors.
Test the caps in the dodgy pcb, nothing to lose.
Shut up harvey, Ok i will lol.
With the VR 2001 in the middle of the front half of the Mainboard you can set the PG-shift (Head Switch). This essentially compensates for the Position of the magnetic Disk under the Drum. About +/- 8 Lines Tolerance. Now a Mainboard that was adjusted with a different Head Drum is used, therefore PG-Shift should be controlled.
As always a great video!! Thank you so much for sharing your knowledge that help us to learn and get the courage to try to fix our machines. Thanks to you I was able to fix my Sanyo Beta VTC-5000. Btw, I cannot wait for the video about this customer :)
Great stuff, really enjoy your educational VCR trips. I am still learning but really enjoying the journey. I have completed a few transfers for local customers and the feedback has been really positive. Not looking to make any money really just trying to offer a good quality service and help local people to preserve their precious memories whilst enjoying the challenge of getting the best possible results. I keep looking out for a reasonably priced stand alone TBC (using machines with on board TBCs at the moment) so if anyone has one up grabs please do let me know. Interested to hear about customers who have upset you Colin in terms of what the issues were and how you dealt with them. As ever, keep up the good work.
Standalone TBCs are even more of a minefield than TBC-equipped VCR decks, IMHO. I have a couple - one is a TV One 1T-TBC-GL that I imported from the US to the UK; the other is a Datavideo TBC-1000 that I took a punt on with eBay, and it paid off (case looks like it has been in a car crash; the innards are perfect).
Interesting to watch your swapping the power supply and boards into the Panasonic unit,hopefully you will solve the issue.
The audio feature on the jvc units was called timescan audio,and it was tied into the dynamic drum set up.the idea was that while in forward search at 1.5, 2 3 5 or 7 times speed you would hear part of the audio from the fixed audio head,and if pausing from play you had a 3 or 4 second loop of sound constantly repeating until you either resumed play or hit stop.sorry to hear you have had some unfortunate times with some customers, I always have enjoyed your videos
Yes do a video about those rare bad experiences. That is very interesting to me!!
The 4700's high pitch whine sounds like the head drum overspeeding, which may be caused by a bad servo ribbon cable connection.
The JVC 7600 are not bad, but I got 2 Philips VR-1100 after them, which are far superior in picture quality as they have 6 heads and S-VHS on normal VHS-Tape called SVHS-ET. Still in use today. Even I got the best results with the Kodak Tapes you used in the video (I purchased usually at Aldi..) Thanks for your video !
Great machines. I look forward to the future rant video. LOL.
I’m still using my 20 year old Mitsubishi HS-M1000 S-VHS machine in 2023.
Nice JVC machine. I have an HRS-5800 I bought from new, it was the flagship editing machine at the time. It died about 15 years ago - must get round to fixing it! Also it's amber VFD had faded to near invisible, very annoying indeed. Look forward to your awkward customer experiences!
Re-View rewinds and replays the last timer recording you did, in one button press. Always liked it on my old JVC
I have a medical Mitsubishi MD3000 SVHS VCR with built-in TBC. When it works, it is fabulous, but on some tapes it trips and does the similar up/down frame jerking as your JVC, quite annoying considering that otherwise the frame looks very stable. Is it just how the TBC is implemented, or is it a symptom of a bigger mechanical issue?
I suspect it's machine design but there are some adjustments which might have a bearing on it, such as tape guide settings, head switching point.
I bought two rough looking S7600s for very cheap a few years ago to try and fix them up and boy was it a mistake. Possibly the most abused machines I've ever seen, all the buttons had been worn clean, they were trash mechanically and when I was able to get one to barely play the head was so worn it looked like those terrible VHS effect horror filters you get on phone apps nowadays. Also, don't get me started on the cigarette smell... Left a very bad taste in my mouth so it's nice seeing this one in such great shape!
I have a JVC HR-S7500 which I bought from new from Comet and that has a set of very similar markings from permanent ink marker pens so I assume these markings were made when the unit was being tested during manufacture. Incidentally I used a picture of this VCR I for my UA-cam channel 🙂
I have a Panasonic AG-W1 do You know if I can rec a VHS from NTSC to PAL ?
I love the old JVC Hifi VHS with the folding down and up doors they break after years of use of the door though but very nostalgic I had the about 88-89 model which was grey had VU meters be able to watch Mono and Stereo feeds of the tape at the same time knobs for volume and balance they are real nostalgia VCRs the JVC.
I would like to work with someone knowledgeable like you Colin to try to disable the Dynamic Drum electronic system by spoofing its checks if a normal non DD drum were to be installed or just lock the DD drum in a neutral position and disable the DD system that consists of a small PCB that connects to the main cassis located beneath the drum assembly. As you know it basically checks for motor pulses every time the VCR is turned on and if it don't find them it shuts down the VCR, A small circuit that mimics the pulses can be added to the DD small PCB using its power, I'm just not electronically inclined to make such circuit, I wrote a procedure over at videohelp for a work around to disable the DD system mechanically by removing two gears one from each side leaving the drum in its neutral position.
I'd love to watch a video of customer troubles. I bet there can be some funny stories there
Always exciting to follow you.
Of Super VHS I have a Panasonic NV-FS200 from 1990 where I have had much of the mechanical parts taken apart due to faults. debugged and collected and now it works as it should, in that area, but there is another error, that is low contrast, a lot of color and the picture falls on the scart output, suspect a fault on the Video amplifier part. Otherwise a nice machine. Then I have a Panasonic AG 8700E from 1993.
I have had 3 of them. and finally, I have had two JVC Super VHS from new, one from 1995 and one from 2003, and my experience is that JVC has had the most stable, durable and fastest running mechanism, they have all been used a lot.
S-Video out (Mini DIN/Hosiden) checked ?
@@TTVEaGMXde No, the picture on the S-VHS out has not been checked, but I think that the Video line in the S-VHS Out goes over the same circuit as the Scart plug, so it would be the same result
@@nostalgoteket.tvogradioark1494 Due to the low input resistance of 75R, bad contacts are very effective. I would prefer not to use Scart due to the very small effective contact area.
@@TTVEaGMXde I can easily try through the S-VHS output and see if it makes a difference. Be right back
have you used a domesday duplicator? and what are your thoughts on it?
I'm aware of those projects which take the RF signal from a video recorder or LD player. I've not worked with them yet but have a LD player I would like to try it on at some point.
My only two VHS decks are a Panasonic NV-FS200 and a JVC HR-S7500. (mentioned them because they are close relatives of the AG-4700 and HR-S7600) Both work flawlessly and I like both :)
I prefer to use the Panasonic with my PCM processor and the JVC for video related stuff, where picture actually matters.
I think the NV-FS200 is a G mechanism, which I believe is what is in the Grundig SVHS machines that I got in recently. I have an NV-FS88 here which I bought from new.
the hum on linear audio, you can improve it by an improvised foil screen carefully applied around the ribbon, grounded at one end
My HR-S7600 stopped playing a tape and flashes Auto continuously on the front panel. I was told it could be a fuse, what do you think?
I can't debug a fault like this remotely, it really needs careful examination by someone with experience in video recorder fault finding, and possibly the service manual too.
@@video99couk I wonder if you can verify or not, that there is a replaceable fuse that is inside the casing by the back panel.
There are 2 major Revisions of the NV-HS1000/AG4700/NV-HS800. They changed up the circuit board slightly and the head drum is a bit different. The service docs (there is a SM for the HS1000 on freeservicemanuals info that has the second revision + service notes at the end) are not entirely clear if the Y/C board+head amp combinations are cross compatible or not.
I wouldn't change boards between the HS1000 and AG4700. At the very least there is likely to be firmware issues, because the AG4700 is not exactly the same as the HS1000 as it includes frame accurate editing.
Quickout Drum is the best name for the Drum that is only prevented from falling out (by trustworthy parcel services) by the very solid ground grinder retaining bracket.
These JVC's with Digipure processing have two menu options that exclude one another. The Digital TBC/NR straightens the vertical lines in the picture and cleans color blotches, but it doesn't prevent vertical jittering that can blank video capture. To do so, you have to engage the Video Stabilizer fuction. But that defeats digital noise reduction and TBC.
The RAM is too small to do "everything".
That's exactly what I have to do with fussy EP speed tapes, too.
Unlike the US models, Video stabilizer was only available on the later PAL variants from maybe 2001 and on. This one lacks it. (Though I think the feature technically present in the syscon chip in earlier models). As far as I know it replaces the vertical sync signal if it thinks it's too corrupted or missing, based on the head switch position, there is a demo on the HR-XVS20 video on my channel. Even the simpler models from the later lineups without any digital processing or TBC have it. The late model JVC (S)VHSC camcorders with TBC also do something similar when the TBC function is on.
Any chanche finding those brakes to JVC vcr:s? Or just try to make new pads.
Probably have to make them. Adding a little strip of masking tape is a good place to start.
@@video99couk Well i actually made new pads to my HRS9600 from round furniture pads. About 2mm height is a good compromise. You just cut it with carpet knife for good size.
Many years back, my NVHS-1000 had the same issue. Panaserv charged my the handsome sum of £500 to change out the head drum motor assy
Really, that implies then that the head drum motor is the problem. Useful information.
I remember using an editing pair of Panasonic AG-4700's at college in the mid-90's, but never came across their consumer versions. I have owned from new the slightly earlier Panasonic FS200, which also has a TBC, but I had so many problems with the picture quality I now only use it for checking contents on tapes not for any sort of transfer to digital. Around 1999/2000, when the prices for S-VHS recorders started to drop to around the £200-300 range, I bought one of those Philips VR1000s (the JVC clone), that vintage of machine has 3D-DNR as well as the TBC which seems to correct most of the noisy chroma issues, especially with older tapes.
Have you ever come across later Panasonics that have the 3D-DNR feature which I think include the HS-850/860/950/960? I'm curious to know how they compare to the JVC's. As far as I've seen the JVC's TBC/3D-DNR are linked together but on some Panasonics the TBC and 3D-DNR can be switched on & off independently, and some Panasonics have the 3D-DNR without a TBC. Thanks.
I'm not that keen on the 950, the pictures look noisy on those. The later, cheaper 930 is a very good player though. The 3D-DNR can be a mixed blessing, I tend to switch it off on the VR1000 because of strange splodgy movement of colours, even though the effect on a test card is stunning.
Thanks, I'll keep a look out for a 930. Found a picture of one and it does seem to have separate TBC and 3D-DNR buttons.
@@jkmac625 The Panasonic NV-HS930 EG has a usable TBC and a 3DNR that can be switched separately. The hi-fi sound is only good if it's not too loud, since the device distorts when playing "fully" modulated NV-HS900 cassettes. Unfortunately, youtubers without an e-mail address cannot get a HS930 TBC on + 3DNR on canopus (ADVC-100) DV-AVI demo file.
There's also the JVC HR-S9500 with dynamic drum. The TBC there is fairly useless as it also trips on bad sync pulses.
Just for the record i came across an AG4700 that did the super speed of the head drum at power on and nothing else and it was one or two caps in the PSU had gone high ESR and were raised on the top.
Feel 100% sure it's a few bad caps in the PSU. Did you check inside the second on even first PSU supplies?
But both PSUs with exactly the same fault, which I've never seen on an AG-4700 before? Seems unlikely, but I will go through one of the power supplies. Other suggestions include the drum itself and the front panel PCB.
My experience too, have a variety of machine available, sometime this tape does not play well in this machine, but very wel in the other.
Overall, the Philips vhs machines do not perform well against my Jvc machines, but they (Philips) are cheap and available.
Philips is good enough for sighting. However, to digitize Video 2000 and VCR/LVC you have to rely on it.
I have three AG4700 and one of them has the same problem and I had to sell it out. I have three 7600 And in my opinion, I like 4700 better than 7600 because I don`t like those svhs which has circuit with Digital Images. I like pure Analog Images😁
Dynamic Drum...... We used to call it..... wibbly wobbly head drum :)
Given the fact that power supplies are a common problem, changing one over from a scrap machine may give you the same fault; why not just measure the voltages / ripple first?
It's a fair point but I know from experience that PSU failure on this particular model, is rare. So getting the same fault twice is really not likely.
@@video99couk This power supply doesn't even have a 1µF 400V starting capacitor. I have never repaired anything else in a Panasonic "VHS" power supply.
i know we are just going to wait to know how bad they are
just abit of fun in some way i have this when buying used A/V gear ebay i win goods and not sending gear ut just because
it ended very low
i have a old mate i don't see any more he buy alot of home quad akai deck and alot of tec's will not deal with him as cost of tec time
is very high
my boss lady under me (my mum) said can't do any more mate fee's any more cost of living hit all work at home people
it's only change cap's over and small things i have to book all the time a spend in fixing now
in the old days i used to move audio of reel to reel easy when you have alot of decks 20 akai 4000 i have now
cost back in the day was very low to do keep alot of deck running can get high over time as wear gets to them i have to spend time
checking them
tis why i cam out of the audio moving game wear on the deck you are getting this with the video decks i see as well
Christ.
I don’t get this? Form someone who use to repair these things. You need the right test equipment and a oscilloscope to set these up. These are old and I’m telling you they need work done because of aging. I take it you don’t know much about all this ? The Panasonic is repairable but it needs a service.
Take a look at my channel and you will see me doing component level repairs on lots of equipment.