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Keen for the Powerwall 3 here in Australia for a new install with inverter integrated.

My SVR4004 had some faults. Symthom: When the video is hot, some reels stops suddenly. Cause, in "motorelektronik" card, TR1363, TR1358. In manual service is BD898 but in my Grundig was TIP121. Just replace. The cause is that when the transistor is hot, internal junction fails. Symthom: Hardly seen green and violet vertical bars. Maybe is needed to adjust Chroma filter, but I solved it adjusting R1811 in chroma card to maximum. Symthom: Low signal in tracking indication. Low amplification by IC1683 TDA2700 in Chroma card? Just replace. I found some rubber rottens with cushion fuctions, I replace it with cable gland rubber. This are used in the reels motors and threading mechanism motors. A "must do" is to replace Roe Roederstein capacitors. Another faulty capacitors are tiny axial Philips caps, mostly in sound card. Note: I've tried convencional VCR tapes, and some tapes with VHS and Beta belts, and works perfectly like "Grundig high density tapes for SVR4004". So, I think there is no a real reason for to use different tapes in this video than in other VCR older video tapes. I think that "Grundig high density vcr tape" was a bullshit for comercial reasons.

THANK YOU SO MUCH, this information is gold

There's something I've been wondering for a while now,& judging by the subject of this video, I think you're the person best placed to answer it. Beta had cleaner tapes are pretty highly priced these days, often reaching over £40. Vhs cleaner tapes are much cheaper. So, as the tapes are the same size, can I slice a section from a vhs cleaner into an empty beta chassis? Or would you just suggest cleaning the heads by hand?

I've come to the conclusion that Betamax sucks.. Lol... I feel your pain bro... 😢😊

It's too bad that no one can have access to your equipment to de mold tape.

30:59 looking at the mechanism and PCB this was not really made by Grundig. The mechanism with the microswitches gives a strong JVC vibe and the chipset on the PCB is Hitachi and the Electrolytics Made in Japan. If it was a Grundig designed gear the higher level signal chips would be Philips/Valvo or Siemens and the caps Frako or ERO.

Wow, what a trip! Yeah those 723s are always a pain in the arse... when you show it the first time on the diagram I was like noooooo... a 723 😅 But it's strange why something was smoking, on the top part of the circuit there is an "electronic fuse" which through that SCR disables the output in case of overcurrent - at least, it should do that...🙄 So basically we had a dead 723 to begin with, and then that tantalum got shocked when it saw again some electrons after who knows how many years of total darkness 🤣And now something else gave up again. Maybe another tantalum had enough? 🙄 Can't wait the next episode 😅

ADAT is a repairman's dream machine and only repair men should own them if they get it to play once then put it away so they can repair it again when they try to use it next time the florescent vacuum displays are highly sought after as they can't be repaired

wow i never saw it in my short life...look this mechanics 4 heavy driver motors two big motors must be drum and capstan others one must be reel and loading

13:55 Without going into detail let it be said that to construct a proper oscilloscope probe attenuation devider you not only need a resistive devider scaling down the DC, you also need to use caps in parallel to the resistor to provide a scaled down path for your AC component. If you dont add any caps the input capacitance of ur scope to ground will form a low pass filter along with your high side atennuation resistor. What you get is a waveform that has low frequency response, no definition or sharp transitions or edges. Just look up the schematics of an average scope probe with inbuilt attenuators, watch the eevblog videos on homebuilt attenuation probes or refer to the literature on passive scope attenuation probes on for example the Rohde+Schwarz website. With your scope being only 5Vpp input you should really invest in a 1:100 attenuator probe. It will not only increase the useable voltage range on the scope x100 but also (and often most importantly) reduce both the capacitive and resistive loading down on the circuit under test by x100.

Does the fibre install have issues with Mac addresses?

49:52 I highly doubt that there is a design flaw in the Reset IC. If you had looked more closely at the schematic, you may have noticed that this IC does not only trigger on Power On, but also on an undervoltage condition in the 5V +5b line. It is clearly shown that this IC 1453-2A uses a precision zener TL431 to derive a 2,56V reference voltage on pin 17, to which the +5b line is compared ( via an internal voltage devider..). If your 5 V supply is marginal or glitching or has hum on it, it may very well cause the IC to keep in reset. Same goes for the TL431 having drifted high in its zener voltage. Since with a too high reference, the release point of this IC would shift upwards too, waiting for 5V which cant be reached. And here is another hint; even tho temperature compensated, if you heat a TL431 its reference voltage generally drops slightly. So the IC woukd release the reset at a lower +5b... Now where have we experienced that? Oh right thats exactly how this circuit behaved! Sorry but instead of altering the circuit it would be a matter of seconds to rig up a TL431 and test the deemed defective IC on a regulated adjustable 5V bench power supply for both the undervoltage lockout trigger and reset release voltage. That way you could get 1000% confirmatuon if the IC is faulty or marginal, or if with your POR redesign you merely coveted up the underlying cause. PS especially if the blue trace in the scope picture at 51:43 shows ur +5B line! Its amplitude rises by only 4,8 devisions on a 1V/ div scope scale. That tells me that your +5b wpuld be 4,8 to 4,9V and not 5V or 5,2V (which most of the Grundig V2000 run their logic boards on).

12:09 Calling a uPC574 a voltage source is kind of wrong. It is a temperature drift compensated 33V zener used to stabilize the tuning voltage feed on tuners. So unless that craptastic tester puts out more than 33V, the uPC574 will always be recognized as a simple diode only.

Great video Colin, I love these in depth videos about real vintage technology. You have a lot of patience! You’ve inspired me to take another look at my machine (when I have a lot of spare time). The main fault on mine is that the capstan pinch wheel solenoid doesn’t engage in play. Any ideas which voltage might be missing? Cheers, Rob.

hi them ohone vid's i just don't like please keep it to the same format i know it may get more watch i just turn it of

18:14 The Firmware in the UK models must be different to what we have here in Australia. When our grid fails the power wall switchover is instant. I do have UPS'es connected to most computer equipment anyway but the most that we get is a single beep from them as they report the the grid did something. No lights flicker and machines not on the UPS don't even notice the switch. Ironically I'm sitting here typing this while the house is off grid since there is scheduled work out on the street. It's winter here and the sun is very low so shading on my solar array from surrounding trees is terrible, but the house is running as normal with the heat pump (reverse cycle air conditioning) is keeping the house a 21º with free solar energy. If the battery gets full it regulates the solar automatically by slightly raising its output frequency. All very seamless.

If sombody like to have almost perfect wow aflater test cattet tape it shoul be order from high speed duplicators that copy the tape up to 100 time daster,. So any wow and flater is almost non exitance. The source of frequency is RF generator. That might be more inportant for speed ajustment. If you like to mesure just wow and flater take the casette tape and record the signal from computer and play and measure on the meter. The number that you get from the wow and flater meter just divide by two. This will be the most accurate measurement that you can make on your tape recorder no mater what profetionaly done tape you will obtain.

40:03 I hate to throw a wrench into your troubleshooting, but there should not have been any smoke escaping at this point. The 15V regulator is protected by a feature called electronic fuse "ELEKTRONISCHE SICHERUNG". And this electronic fuse is build around the thyristor/scr TY447 2N5081G. And this protection works as follows; TY447 monitors the voltage drop across the resistor R451 (0R22). If the output current rises the voltage drop across R451 increases. If that voltage across R451 exceeds the Gate to Cathode trigger voltage of TY447, the SCR conducts and puts a positive voltage from the raw 22,6V line via R443 onto the node of R446/R447 and thus effectively pulling pin 2 of the uA723 high. As a result the uA723 has to immediately switch off any base drive to the pass transistor T449, and the whole 15V output will shut down. The cleverness with this circuit is that it latches the supply in the shut off mode and will not let it come back up, even if the short disappears. Why is that so? Because like any thyristor SCR TY447 will stay conductive as long as it has any Anode to Cathode current flowing through it, even if the Gate drive (hence excessive output current thru R451) disappears. As a result after an overcurrent trigger event, the pin 2 on the uA723 will stay pulled high and the 15V supply will stay shut down until the whole VCR is fully power cycled. I wonder where we did see this behavior... Oh right, the previous Grundig SVR 4004 did exactly behave like that; the 15V line IMMEDIATELY shut down on the overload caused by the bad tantalum and stayed shut down until a power cycle. What this means for this VCR is, that either this powersupply board is a different revision missing this electronic fuse feature (I hardly think so), or the SCR TY447 is bad or was disabled by a previous tech troubleshooting, or the "NEW" uA723 that you fitted does not handle the signal to pin 2 correctly, meaning it is a fake. The latter can be proven easily by upon proper operation passing voltage from the 22,6V rail thru a 1,5k resistor into the node of R446 and R447, and watching if the 15V line shuts down. Whatever you do, Bottomline is; The 7V you saw on the 15V rail before the smoke escaped should never have happened. The overload shutdown should have kicked in instantly and lasted until cycling the power. Just like seen on the previous 4004. Seeing how these VCR are prone to problems with tentalums on the 15 Volt line shorting out, I strongly suggest investigating into why this powersupply did not shut down the 15V rail on overload properly, unless you want to fit a fuse in the 22,6V rail to make up for that protection feature not working. Side note; Why didn't you use a current limited(!!!) bench powersupply to externally feed the 15V rail? You could have easily seen how much current was drawn and which module was the culprit.

Do I remember correctly, that the C9 is unique since it is the only VCR ever produced for consumers with a HF-Modulator that is capable of transmitting stereo sound over HF?

Hi what is that little Tascam media player you're using in this vid?

4:54 - I mean, I admittedly saw a dinosaur when you were further away from it, but yeah. That's totally a cat!

What do you get if you disconnect the composite link and just leave the dub cable connected?

I've had sooo many cascading faults with dipped tantalums that at this point, if the unit is 30 or more years old, I start with replacing all of them before even attempting a power up. If it's a DC rail decoupling cap, I replace it with a low-ESR electrolytic, if it's a low value coupling capacitor in the signal path, I use a film capacitor. SMD tantalums last longer because their epoxy coating is much thicker. I have two NOS video waveform monitors, when I powered one up, a dipped tantalum smoked. It was on the 5v rail, I've cut it out. Then the next one smoked, rinse and repeat ~15 times. When all the tantalums were removed from the 5V rail, the unit started working. For about a minute, then an other tantalum, this time on the 15V rail shorted out. I haven't powered up the other one, as I want to make a video about it. It will probably be a smoke machine just like the other one. And they are not even that old, from 91 or 92 IIRC, and the tantalums are KEMET or some other good brand, rated 16V on a 5V rail. They were stored in a damp basement, their cardboard boxes are moldy, so their aging was accelerated. One of the big enemies of tantalums is moisture, it slowly gets through the thin epoxy coating. The other enemy is oxygen, which also penetrates through the coating. Hermetically sealed metal can tantalums on the other hand, are everlasting, as long as they are protected from voltage surges.

I have a printed original version of the service manual with an appendix. Grundig changed the pinout ofB1 and B4 during production. They turned it around. 1 is now 10 and 10 is 1. In the sve 4004el there is another schematic of the power supply.

Really valuable videos with lots of useful information. Thanks for sharing with us.

More Video 2000, please?

B4: 1. Permanent -26 V 2. GND 3. 4. Motor Control Board 13 (I assume pin 13) 5. Locating hole 6. To clock 9 7. Permanent +12 V 8. Syscon board 23 9. IF fine tuning +15 V R - active when the machine is on and a function key has been pressed, relay is latched +15 V E - active when the machine is powered on but idle

Thank you Colin tricky repair,

Are you going to put that in the obselete junk museum? 🤔

After an hrs worth, success then the stubborn old coot still won't wave the white flag. Oh well more fun to have...

Your ability to trace the faults is very impressive.

I wanna see you working on a shotgun microphones, specially Sennheiser, thanks for your patience

This is "just" cheer electro investigative drive, a rare sport... Must be praised for the patience, courage and honesty. When this early video machines were made, I'm sure no one would ever think that 40+ years later, a clever brit would diving into German junk like this. Someone's footage on that rare vintage format, will be thankful, when brought back to existence and digitized to "eternity". Video empowers people! Cheers 📼

Max Grundig wanted this format to be built, so it was built. Market analysis did not matter to him, he followed his "stomach" feeling. Much to the disadvantage of the company.

Is it really that much better to use a dub cable for U-matic? I recently did a test transfer of a low-band tape recorded from a TV station in Baltimore (I think it was recorded around 1992?), and I simply just used the composite output going into a Sony DSR-PD150 DVCAM camcorder, and passed it though into my computer over Firewire. I then processed the video using VapourSynth/StaxRip and deinterlaced it and upscaled it to 1080p for RUclips. Not to plug my channel but in my repair video of the Sony VO-7600 I put the transfer test at the end of the video and it looks great for a low band tape. The color quality on U-matic is already poor from the 688kHz color-under encoding so I don't think there's much to be gained using a dub cable. I believe the chroma quality is better with hi-band PAL so that might be better to use a dub cable.

That one was a bummur..but, you WILL fix it, no doubt about it. Excellent stuff.

There are still many blue tantalum capacitors and FRAKO electrolytic capacitors in the device.

Perseverance will always win rewards, great content

Bloody Tanty's. (and light bulbs. ha ha)

thank you for the video. thank you for showing how precise one can chase a fault which turns out to be a working component. it is part of the process and not giving up to easy. the desintegrating plastic parts are a real pain with some manufacturers products. others might say they were not so as long as the company expected this machine be of use for anybody but you repairing and using this prooves these voices being wrong.

panasonic nv-hs930eе, no vedeo signall , audio is ok

Despite me not having time to watch this from start to finish, thank you for filming it!

Thanks for another excellent repair video. I remember a mate of mine had one on the 1970s?

Like "aviation" connectors, not all Hirose connectors are the same. I used to use U-Matic machines at work years ago, so I know from experience that the Hirose connectors that Sony used are completely different from the ones that I recently had to track down for a Hitachi CCU-RCU cable. The Hitachi ones were smaller, had only 4 conductors and the connector had a pull-to-release latch, not unlike those on some old Nagra tape recorders. I'm glad it's not my problem! But I can say that using the dub output was the best for feeding a TBC back in the day. Sadly a lot of connectors are referred to with proprietary "slang" names that often had nothing to do with what was on the parts sheet. Back in the day, the familiar XLR connector was known as a "Cannon plug" in my area, because ITT Cannon was the original manufacturer.

hirose is pronounced hi-row-she... digikey used to sell them... maybe they are out of stock, or have stopped sourcing them

I have two and a BRC. One is very low hours, the other I think needs and Idler and belts. Very noisy during FF/RW and stalls near end of tape. Ordered from E-bay, hopefully that'll do the trick. Will master to Alesis CD recorder.

I loved Denis Norden too he had a great sense of humour i miss him. He and Frank Muir together were brilliant comedy writers, they were much better then the comedy writers today who can't writer a funny line to save there lives. I also miss seeing Denis Norden too on the programme 'It Will Be Alright On The Night" it was always his programme, seeing him with his clip board in hand. The programme is now presented by Griff Rhys Jones, I don't mind Griff in general but not presenting "It Will Be Alright On The Night" it's not the same without Dennis. This is a brilliant and very interesting documentary on the Philips N1700 Video Recorder I just wonder how many of these machine still work today, if they do and does anybody use one.

Hi. Some time ago i bought a used DVW-700 digital betacam camera. It has some very strange behaviour with threading motor. Can anyone please help me with this issue. I have basic knowledge in electronics and tools like oscilloscope etc. I tried referring service manual, but it didn't help.