Component level repair the Super-rare Grundig SVR4004. A format of only one model. Part 3.
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- Опубліковано 14 лип 2024
- Super Video Recording was a doomed video format from Grundig. Based on the VCR (N1500) and VCR-LP (N1700) cassette, this exquisitely rare format used a slightly improved tape formulation to allow for up to 4 hours on a cassette originally designed for 1 hour maximum. Only one model of machine was built, the SVR4004. Shockingly, we have two of these. Today we go deep component level repair on our second machine, but our first machine comes in handy along the way.
Part 1 of this video: • Super-rare Grundig SVR...
Part 2 of this video: • More on the Super-rare...
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, almost works on fault demo
01:43 Power supply checks
08:28 Start homing in on syscon (ablaufsteuerung = flow control)
09:04 Big clue from working machine
11:02 Check and clean switches
13:38 Test syscon (ablaufsteuerung)
15:59 First pictures
18:57 Work on syscon (ablaufsteuerung)
34:32 Test it
35:04 Conclusion - Наука та технологія
The dogged persistence and methodical fault finding at work here is something to be admired 10/10
Very nice, Colin - there are always people ready to criticize, just ignore them. Yours are some of the most enjoyable videos on UA-cam - if someone thinks they can do better, they should start their own channel
A little faulty component can have big consequences. Great job! Thanks for posting.
Well done! What a long way to find that little, improbable culprit! In any case, as it is confirmed again here, it is always good to have a second, working unit to narrow down the fault finding to a particular board.
Brilliant, a little dark capacitor was found guilty! That machine is looking good and playing a nice picture. Colin just keeps on pulling these old vcr rarities back to life.
Cheers 🍷
Nicely done sir. Nothing like a little logic and some perseverance. Well done 👍
Thank you Colin excellent work
I remember Sam from 'Look mom no computer' did a song and dance with the lyrics "you don't know what you're doing" as a reply to all those who made comments on his working methods in repairing an old church organ he had bought.
Manual tracking with meter that you see signalstrenght you have on JVC HR-S 5000 SVHS come out 1988 . Very good to use with some tapes .
I wasn't aware of that feature on a JVC. Actually I think I may have owned a new one of those for a couple of weeks, back in the day. It kept breaking down and I replaced it with a NV-HS88 which was reliable (it still works!). So I never got to learn about all the JVC's features.
S stands for Sibatit (SIEMENS ceramic type) capacitor. Capacitor or IC, the main thing is that SIEMENS is to blame. I have already written that you should only keep SVC recorders in a pack so that you can try out which one suits the recording device best. Market researchers have advised Max Grundig against SVC recorders. The ITT Videorecorder 241 is the rarest variant of this evolutionary dud. Since the transistor has a 100k Ohm resistor and the IC has a 6.8K Ohm resistor, the capacitor was the most likely cause. But as a TV Engineer, I wouldn't have found the problem any faster. Well done👍
That's right, machine/tape inter-operability was not a given on this format.
Ciao, che pazienza nella ricerca del guasto e come lo hai risolto. Bisogna farti i complimenti: sei molto bravo e seguo molto volentieri i tuoi video. Buon lavoro, ciao
Good job and those people that complain are big mouths that dont know what they are doing
Given that this is the level of repair I do on vintage computers I was well entrenched in this. Must admit I was slightly disappointed when you didn't airpunch or dance around the room when it started playing properly :D Good stuff, cheers!
Great fault finding - so satisfying!
Nice work. Time consuming, but worth it for a rare machine.
(I think the mechanism could do with some oil. LOL.)
Such careful and difficult work! Ultimately of course it's a futile battle against the basic entropy of the universe that pushes everything towards disorder and chaos. But we can gain temporary victories such as repairing obsolete video machines. It's a pleasure to see this.
Always seem to be fighting that entropy problem.
Thank you
on mine, the light bulb is burnt out. The machine still works normally.
Looks like you have pretty much the same recording on that test tape as I have...
I tried my best to translate the pinout. Schacht is usually a narrow pit or a (mine) shaft but in this instance it's the cassette well. Fuehler (more usually spelled with an umlaut ü instead of ue) means sensor, error would be "Fehler". In a decent effort to make everything sound complicated, the Grundig engineers used the word for the tape type detection switch. The "Schachtkontakt" tells the machine whether the cassette tray is up or down. If that's constantly pulled low by a faulty capacitor, the machine gets confused.
1 - Locating hole
2 - GND
3 - +15 VE
4 - Flashing indicator (whatever that may be)
5 - Cass button (eject)
6 - Indicator „Cass“ (no tape)
7 - Play button and indicator
8 - FFwd button and LED
9 - Rew button and LED
10 - Stop button and LED
1 - Timer Record Start
2 - Timer Rec button
3 -
4 - Rec signal to power supply
5 - Tape end switch
6 - Rec button
7 - 50 Hz
8 - S1-B
9 - +15VR
10 -
11 - Y attenuation
12 - S2A
13 - FFwd signal
14 - S3
15 -
16 - N1
17 - GND
18 - N2
19 - Locating pin
20 - +15VE
21 -
22 - Cassette (type detect) switch
23 - On/off relay
24 - Cassette tray switch
25 -
26 - Unlace
27 - Play
28 - Rew
29 - Lace
hi know about the trolls you get some people i know told me your having a channel is likely get alot of them
yes i work on audio gear i have a brenel mini 8 i have working just waiting for pinch rollers to come back
i have all the plans for it you know that hit a mole game very like that the repairs keep pop up all the time i am winning the game now
there a sound craft 381- 8 for sell best not to buy it 200 uk just to get it going been there with a 600 reel to reel
this video is not a money pit just like that game
love the video's keep them coming
These tape cartridges look a bit similar to the Quasar "Great Time Machine" marketed here in the US back in the late 1970's.
They look similar. But the N1500, N1700, SVR formats all recorded full field video so were "modern" video formats. The Quasar system was skip field so it dumped half the video information.
The sound of heads at minute 17 is caused by an excessive tension of the tape. In spite the video has an optimal calibration from factory, maybe is necesary to adjust and loose a bit the tension of tape, because the tapes are subject to ageing and the sliding is not good as it should be. It can be a nightmare to adjust differently the tension adjust for every tape, but it happens, some too loose, some too tenses.
Edit: Tension adjust is at page 12 figure Ab.7.1. Sometimes there is another problem, tape tension is not the same at the beginning then at the of the tape.
It settled down after a few minutes, but yes the back tension arm was bouncing around a bit at first.
@@video99couk
So, in that case, apply the gold law: If it works, don't touch it.
Another tip: Capstan motor screws are not torqued at the end. This screws are part of some kind of capstan angle adjust, so, don't touch it. You can see it at 2.8 "wechsel des captanmotors" page 20.
The best solution for the bad hair day is just go for it, blade one on a good set of electric clippers bought with all the money you'll save from not buying hair dye and Grecian 3000 (or whatever it's called) Simple 👍
Schachtkontakt; i would say that is a contact which switched if the door is closed or a cassete is inside
Schacht means drawer in our case, so it is giving the casette drawer status.
Btw. could this be the earliest full logic controlled VCR? All VHS or Betamax machines I know of had mechanical switches before 1981. (also - professional use VCRs don't count)
I think this is newer than the Sony SL-C7.
The professionally-targeted Grundig VCR601/Philips LDL-1100 portable VCR format machine was incredibly advanced for 1977 and had a logic-controlled transport. If that's a little esoteric, there's the domestic market VCR-LP format Grundig VCR4000 which predated the SVR4004. The VCR4000 and SVR4004 were externally very similar, with the latter differing internally to handle the needs of the higher density SVR recording format.
Almost forgot: Grundig had a VCR format machine targeted to the domestic market: the BK 3000. Externally clearly of the same lineage as their VCR4000 and SVR4004, also with a fully logic controlled transport. I think this model appeared in 1976, one year before the VCR601.
@@video99couk I have an SL-C7E and it was early 80s. Internet says it came out in '79 so the SVR4004 is a bit older. I actually grew up on an SL-C6E which 4 year old me inserted a buttered toast (my parents had to tape a straw to the vacuum to get the crumbs out of the mechanism...), I thought the C6 would be the predecessor of the C7. Although the C7 looks decidedly more retro, it has more functions. And almost identical circuit boards. They both have the same problem: No control track / capstan lock. Whenever I take them apart and start scoping around, as soon as I get close to where the problem is, the problem just disappears and they just start working again. Even after reassembly. Until I stop using them for a few days. Sounds like capacitor, doesn't it?
@@jchunter Whoa! Awesome info!
Still it looks as if that doesn't change history - it still looks like it's Grundig who invented the full logic VCR.
*sigh* back when Grundig was World Class... in the 80s they quickly became irrelevant and then the cheap far-eastern companies finally took over.
In 1973 they came out with a 14 inch / 37cm portable colour TV that was fully solid state (neon indicator bulbs for the channel selector also don't count - the HV rectifier/tripler is also solid state) and used a (Toshiba made) in-line CRT. Very modern... apart from the power consumption... 110W... compare that to the late 90s, they were down to 35W on the same screen size. (still, compared to the 160-250W a similar sized tube colour TV had)
My dad worked for NCR and gave us a techwctronix 555 4 trace oscilloscope what tech for the 1950s or early 1960s when it was built service able and. Working into the 1990s when we got it from our dad.
Your equiet ent shows how engineering won over cost.
lots of static it seems 😏
I seem to remember that Grundig and Philips behaved disgracefully in the day, several silly formats, different tapes for each and as soon the format was discontinued no more tapes were made! 😡
I have one my shorts