Repair of a Braun visacustic 2000 digital 8mm projector - Page 1
Forum section: electronics / repair

author: BU508A
author_rank: Super Contributor
timestamp: April 02, 2020, 08:27:37 pm
content: Braun visacustic 2000 digital 8mm projectorHello,some weeks ago, I got this Braun projector on my desk in the Reparier-Bar, where I'm volunteering as a repair guy. The customer described the issue as a "pumping noise". Besides that, everything else is working fine. Plugging in the loudspeaker and power it up showed a pumping noise, depending on the volume setting.I've opened the projector and a cold shiver was going down my spine. What an ugly construction! Nearly unservicable. Cables here, PCBs there, lots of mechanics and all this mess in a very tiny space. Ungh!My suspicion was, that there is something wrong with the supply voltages, so I measured the voltages coming from the power supply. 31V, 24V and another one, all very stable and accurate. Blimey!I told the customer, it is impossible for me in this short time to repair this. Even without any schematics. The customer begged me to try it and finally I agreed to take it home, looking for some kind of service manual and try to repair it. I regretted it the same second, but I have promised to try it. Sigh. I am really softhearted.I tried to find some schematics via Google, no success. All promising links are dead. I startet a request at the Schaltungsdienst Lange in Berlin. They are known for their huge collection of service manuals for a lot of devices in consumer electronics.Some days later they came back, told me: "Nope. We don't have any kind of manuals for this Braun projector." Blimey!So, I started again a desperate attempt to get a schematic or manual and then I found a German forum (https://www.filmvorfuehrer.de/) where finally a kind soul helped me with a schematic of this bloody thing.Ok, you little sucker, let's go! I looked for the volume control and saw right before it two little OpAmps (TAA861A) and measured there their supply voltage, which should be around 18.5V. Yes, the 18.5V were there and look! The voltage is pumping like the noise in the speaker! Aha! Desoldered pin 1 of one of the OpAmps and there was silence on both output channels. Could it be, that one of them is broken?I've ordered two spare parts which I've found in the bay. I've desoldered the OpAmp completely, put the new one in and ... Dang! The Return of the pumping noise! Grrr! Checked again the schematics and there was this suspicious looking electrolytic capC115C135, 220µF. I've desoldered one leg and soldered a new one on the PCB. Switched it on aaaand ... silence. YES! Pulled out the culprit and measured it: zero µFarads. This thing is completely dead. Since the one I've used for the testing was too big I've ordered some more convenient spare parts which should arrive by Saturday.And here for you are some pictures of this bloody thing. Enjoy!Right side:Upper right side:Lower right side with some nice switches:Left side, lots of DIN connectors:Projector lens:Upper right side, film transport overview:Transport system, detail:The halogen lamp:The place, where all the magic happens:The fan for the cooling:The motor:Overview electronics left side:The transformer:The PSU PCB:A controller board, I think:A crappy connector construction:Questionable assembly of the 24V linear voltage regulator:same funny construction here as well:Audio power amplifier:left from the switch, top left from the yellow cap, behind the grey cable sits one of the TAA861A (the one, which I pulled out):right side with the tone controller:detail view to the illumination lamp and a power transistor:left bottom side of the audio main PCB:right bottom side of the audio main PCB:This is one of two NOS TAA861A:This is the deaf capacitor:And for completeness: the schematics of this poor thing:Thank you for watching this.Edit: fixed typo

author: core
author_rank: Regular Contributor
timestamp: April 03, 2020, 06:57:49 am
content: You mean C135, 220uF, on the 18,5 V rail ?Interesting schematics, it remember me the days repairing audio tape recorders ...

author: BU508A
author_rank: Super Contributor
timestamp: April 03, 2020, 08:21:36 am
content: Quote from: core on April 03, 2020, 06:57:49 amYes, you are right. Typed the report from memory instead of checking it again.Thanks for the heads up.

author: coromonadalix
author_rank: Super Contributor
timestamp: April 03, 2020, 06:20:53 pm
content: Bring back souvenirs too

author: Kimpen
author_rank: Newbie
timestamp: April 18, 2020, 06:35:19 am
content: Hello!I'm new to the forum and found this post describing my same problem...I have the same projector with exactly the same problem and couldn't believe to have found the solution to this issue!Unfortunately, it doesn't work for me...I replaced the C135 capacitor with a new one 220uF 25v (insetad of the original 40v) but the pumping noise is still there...So, reading your post, I followed your suggestion to check the voltages of TAA861A and on Pin 1 I get a value oscillating around 18,5v, very unstable!Any suggestion?Thanks in advance

author: Haenk
author_rank: Super Contributor
timestamp: April 18, 2020, 07:58:54 am
content: I would consider all electrolytic caps in there being sub-spec or dead, they certainly need to be checked.

author: BU508A
author_rank: Super Contributor
timestamp: April 18, 2020, 11:41:52 am
content: Welcome to the forum.Quote from: Kimpen on April 18, 2020, 06:35:19 amIs the pumping noise on both channels? Does it change when you change the volume?Have you checked the 24V before the R155? Is it stable?Have you tried to desolder Pin 1 of one of the TAA861A?Btw, I have replaced the 220µF/40V with a 1000µF/35V. I have soldered it on the bottom of the pcb.I suggest to try a higher valued capacitor than the 220µF, perhaps this will help.And yes, as Haenk suggested: I would recommend to check all the capacitors on the power supply pcb. This should be easy to do, because it can be reached easily. You have certainly found out, that getting access to all other components is a real pita.

author: Kimpen
author_rank: Newbie
timestamp: April 19, 2020, 02:27:24 pm
content: Hello! Thanks for the answers...Before completely removing all the capacitoirs I would try to find a simplest way...As you have realized by your self, to acces to the audio board is quiet a nightmareand I even don't understand how you were able to replace the two TAA in your first attempt, without removing the upper part of the projector, which is not so simple.Coming to your questions:Is the pumping noise on both channels?Yes, on both channels (with Stereo mode activated)Does it change when you change the volume?Yes. I add that it is even higher if I press the REC buttons, and the recording level leds flashes with it!Have you checked the 24V before the R155? Is it stable?Yes, 24V exact and very stable!Have you tried to desolder Pin 1 of one of the TAA861A?No, this is something I'm bit worried to try....I would like to add that I started to check also the Oscillator Circuit Board (i.e. the frontal small board with leds) and i found on C304 only 11V instead of the indicated 15V.I can try to replace the 220uF (C135) with a bigger capacitor at first.Thanks

author: BU508A
author_rank: Super Contributor
timestamp: April 19, 2020, 04:52:20 pm
content: Quote from: Kimpen on April 19, 2020, 02:27:24 pmSorry, I should have been more precisely. I was talking about this board:QuoteThis was a lot of cursing, fiddling and putting the tongue in the right angle.I needed to short the pins on one side of the TAA861A to get it in place.QuoteOk, this means the issue has a common cause on both channels.QuoteOk, this means, it must be before the volume control potentiometer.QuoteOk, this means, the issue cannot be in the power supply unit and must be after R155.QuoteI used some solder wick (1,5mm) and lots of flux. It helps also to put some solder on the solder joint.Don't worry, be careful and do not heat too long the solder joint and it'll work.The reason why I did this was to check, if reducing the load will do any change and if yes, which oneof the TEA861A is probably broken.QuoteI think, the reason for the pumping noise is too much load on the 18V rail. It is possible, that in your case another capacitor is broken.QuoteYes, I'd do that. Trying the easier things first.Good luck with it.

author: james_s
author_rank: Super Contributor
timestamp: April 19, 2020, 07:18:01 pm
content: I'd start by replacing any of those electrolytic capacitors with the hard plastic shell. I've found a lot of those in 80s-90s European car electronics (ECU, clock, speedometer, etc) that have failed.

author: Haenk
author_rank: Super Contributor
timestamp: April 19, 2020, 09:32:20 pm
content: Quote from: james_s on April 19, 2020, 07:18:01 pmIf you see a FRAKO - run! Or replace it

author: Kimpen
author_rank: Newbie
timestamp: April 20, 2020, 03:31:48 pm
content: HiI have a great news!I replaced the C135, 220uF 25V with a bigger 2200uF 63V and it works!!!The little remaining problem is that this is even bigger in size and there is no space to correctly place It on the board.Now I ask what could be the minimal value I can use in order to have a smaller physical size in order instead of placing on the back side of the board.Any suggestion?Thanks!

author: BU508A
author_rank: Super Contributor
timestamp: April 20, 2020, 04:41:14 pm
content: Quote from: Kimpen on April 20, 2020, 03:31:48 pmVery nice!QuoteThe original capacitor (C135, 220µF/40V) has a length of 26mm and a diameter of 11mm.How about this one? It has 1000µF/35V and 26x13mm.https://www.mouser.de/ProductDetail/Cornell-Dubilier-CDE/108TTA035M?qs=sGAEpiMZZMu3dWSqd4Tl0OIl6dT4vs0m8wtIQNvyWU0Bpu8H8ORCpA%3D%3D

author: Kimpen
author_rank: Newbie
timestamp: April 20, 2020, 08:07:44 pm
content: Perhaps I misunderstood your suggestion when you told me to use a 2200uF, because I thought I have to use exaclty this and no simply a capacitor bigger than 220uF (even if I didn't understand why...)Of course I have smaller capacitor like 1000uF and in this case my problem is no more a problem!However I would like to try again with a new 220uF but higher voltage, let's say 63V.Thanks a lot for your support and exaplanations!

author: BU508A
author_rank: Super Contributor
timestamp: April 20, 2020, 10:03:17 pm
content: Quote from: Kimpen on April 20, 2020, 08:07:44 pmThat's easy to understand, why I suggested to use a bigger capacitor.When I desoldered pin 1 of one of the TAA861A, the pumping stopped.Replacing the TAA861A doesn't help. Therefore it must be a load problem.The C135 capacitor is a kind of energy store. When the load is too high,the voltage goes down. The load decreased, because the voltage has sunkto a certain level. Then the capacitor recharges via R155 and the voltageincreases until the load kicks in again and suck all the energy from the cap.Then you have this pumping noise. With a bigger cap, chances are good,that the voltage is stable enough and it won't become unstable again.QuoteIt is not necessary to go above 40V. Even 35V are absolutely sufficient.It's a question of the capacity. I tested it with a 1000µF which I had at handand it worked. Measuring then the C135 proofs, that it was dead.That's all.Hope, I make it a bit clearer for you.

author: Kimpen
author_rank: Newbie
timestamp: April 23, 2020, 08:03:55 pm
content: Yes, everything is clear about your reasoning.Thank you so much for your explanation.

author: Mikehiss
author_rank: Newbie
timestamp: September 22, 2020, 07:58:41 pm
content: Hello, would someone have the schematics of the Visacustic 2000 ? I can't read the posted one...Many ThanksMikehiss

author: BU508A
author_rank: Super Contributor
timestamp: September 22, 2020, 08:16:30 pm
content: Hello Mike,Quote from: Mikehiss on September 22, 2020, 07:58:41 pmI'm not sure what you mean. I've just tested it and I can read everything. Please keep in mind that the image size is huge.Have you tried the following?- right-click on the image- view image (wait some time until it is fully loaded and the browser has rendered it)As a plan B you could do this:- right-click on the image- download image to your computer- open the image in a grafik viewer, for exampleIrfanview(windows) or gimp (linux)Hope that helps.

author: Mikehiss
author_rank: Newbie
timestamp: September 28, 2020, 08:55:05 am
content: Hello,Same story : replaced the C135 with a 220/40 and...pumping noise appeared !Replaced with a 1000/35 and....fantastic !https://www.amazon.fr/Aerzetix-Condensateur-chimique-1000%C2%B5F-%C3%9810x20mm/dp/B01MYCCDE8Many thanks for your clear and accurate explanation!!!Mikehiss

author: BU508A
author_rank: Super Contributor
timestamp: September 28, 2020, 08:56:25 am
content: You are welcome.

author: vidalv
author_rank: Newbie
timestamp: January 28, 2021, 11:30:17 am
content: Hello all !I came across the site, on the forum, "Repair of a Braun visacustic 2000 digital 8mm projector" which seems very close to my broken device.This is a Visuacustic 100 multiplay model and I have some wrong contacts.Does the diagrams provided free of charge by BU508A (Bravo for the pictures) seem close to you or do you know where I can find it (for free) in order to do the electrical checks?Thanks for reading.Vincent.

author: BU508A
author_rank: Super Contributor
timestamp: January 29, 2021, 01:33:31 am
content: Hello Vincent,welcome toe the EEVBlog forum.Quote from: vidalv on January 28, 2021, 11:30:17 amI cannot tell, how similar those devices are, because I don't know your Visacustic 100.I got the schematics from a friendly soul in this German forum:https://www.filmvorfuehrer.de/It seems, that there are a lot of experienced people around and maybe one of them can help you.Another place where I'm looking for schematics is the "Schaltungsdienst Lange" in Berlin.They have a huge archive and the copies you'll get are very good.I've asked them for the service manual of the Visacustic 2000 digital but they didn't have it.But, you'll never know, perhaps you'll have some luck with your Visacustic 100. Keep my fingers crossed.Good luck with your repair.

author: vidalv
author_rank: Newbie
timestamp: January 29, 2021, 08:12:11 am
content: Hello and thank you BU508A,I looked on the Berlin site but it looks like it neither has anything from Braun.I asked the same question on the other site, to be continued.Thank you for your support !Vincent.

author: dejoro
author_rank: Newbie
timestamp: April 10, 2022, 10:17:32 am
content: Hello,I live in France and I came across this site and your message BU508A by chance.But I'm already stuck before going to test the capacitors designated as probably "sick", because I don't see how to get the board out of the power supply.Do you have a tutorial that explains the disassembly. I own the Visacustic 1000 but I think it should look like the 2000.Thank you all for helping me.Denis

author: vidalv
author_rank: Newbie
timestamp: April 10, 2022, 10:33:21 am
content: Bonjour @Dejoro,I'll send a PM (pour discuter en Français)@+Vincent.

author: BU508A
author_rank: Super Contributor
timestamp: April 11, 2022, 02:49:58 pm
content: Quote from: dejoro on April 10, 2022, 10:17:32 amBonjour Denis,sorry, the only document I own are the schematics which I've placed in the first posting.Disassembling of those machines is really a pita and the only advice I can give you, is: take pictures. Lots of pictures. From different angles.Good luck with your repair.