Component level repair the Super-rare Grundig SVR4004. A format of only one model. Part 3.

[@chillidogkev]

The dogged persistence and methodical fault finding at work here is something to be admired 10/10

[@JacGoudsmit]

A little faulty component can have big consequences. Great job! Thanks for posting.

[@lucianobellebono5835]

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

[@TigerBoyRS]

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 🍷

[@richrootes]

Very nice, Colin - there are always people ready to criticize, just ignore them. Yours are some of the most enjoyable videos on KZbin - if someone thinks they can do better, they should start their own channel

[@organfairy]

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.

[@janosnagyj.9540]

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.

[@Mrlaurens1987]

Good job and those people that complain are big mouths that dont know what they are doing

[@more.power.]

Thank you Colin excellent work

[@TTVEaGMXde]

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👍

[@video99couk]

That's right, machine/tape inter-operability was not a given on this format.

[@binarydinosaurs]

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!

[@frankowalker4662]

Nice work. Time consuming, but worth it for a rare machine. (I think the mechanism could do with some oil. LOL.)

[@cromulence]

Great fault finding - so satisfying!

[@jameswarner3599]

Nicely done sir. Nothing like a little logic and some perseverance. Well done 👍

[@stefancarlberg7806]

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 .

[@video99couk]

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.

[@atoptip6193]

Each time you say, “power supply,” I have a double take since I hear it as “pacifier” (baby’s “dummy,” in UK-speak). Maybe it is subliminal - one may cry and need one with this machine.

[@vintagecameras9623]

Thank you

[@RebeccaTurner-ny1xx]

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.

[@video99couk]

Always seem to be fighting that entropy problem.

[@Ragnar8504]

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

[@Zoli1972s]

@27:23 Anzeige Cassette / Display Cassette / Cassette Anzeige says the same thing, namely the cassette LED on the front panel. Maybe, during development, different departments at Grundig were developing different parts of the machine, and they just didn't talk to eachother about a naming convention for pinouts, like we do today. Additionally, there was no norm for naming such things in place yet. Today, it seems like a very unprofessional way of developing, in particular for the naming "Fühler" which translates to "feeler", which makes me thinking, that the person that gave the pin that name was not a technicinan at all. They would probably give it the name "Schalter" (switch) or "Sensor", the latter a bit off I know, but still more technical than calling it "feeler". BTW, I just wanted to mention that once back in the day, at the beginning of the 90s, I also owned one of this machines, which I found in the trash. Unfortunately, mine had a missing cassette tray, and I had no cassettes for it, so I was unable to use it for anything, and finally dumped it in the trash again.

[@bobsbits5357]

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

[@senilyDeluxe]

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...

[@manolomos]

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.

[@video99couk]

It settled down after a few minutes, but yes the back tension arm was bouncing around a bit at first.

[@manolomos]

@@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.

[@senilyDeluxe]

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)

[@video99couk]

I think this is newer than the Sony SL-C7.

[@jchunter]

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.

[@jchunter]

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.

[@senilyDeluxe]

@@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?

[@senilyDeluxe]

@@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)

[@davidcocks2403]

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.

[@chillidogkev]

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 👍

[@douglashoff95]

These tape cartridges look a bit similar to the Quasar "Great Time Machine" marketed here in the US back in the late 1970's.

[@video99couk]

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.

[@batmandestroys1978]

Ignore keyboard warriors! You are in the same league, as mend it mark and 12voids! That indeed is high praise! You 3 are geniuses'!

[@video99couk]

I'm not sure I am, but thanks for that thought!

[@dominik.jokiel]

Schachtkontakt; i would say that is a contact which switched if the door is closed or a cassete is inside

[@janosnagyj.9540]

Schacht means drawer in our case, so it is giving the casette drawer status.

[@atoptip6193]

Also, and not to sound like one of your “detractors,” but seems like everything that goes wrong with these machines has to do with one crap-icitor or other…would it not be easier to just change them all? I know it is not as exciting nor does it have that “eureka!” moment like actually finding the one cuprit but, you know, sooner or later another one will go. They recommend that approach for old radios, this of course has many more. I cannot believe what low quality stuff Grundig has used!

[@video99couk]

Replacing every single capacitor would take forever and result in having to re-align all the electronics with unavailable service tools.

[@ViegasSilva]

lots of static it seems 😏

[@vintagecameras9623]

I have one my shorts

[@normanmackenzie8130]

Dont listen to people, who dont know, their derriere from their ulna...