That Mitsubishi EPROM is now 30 years old. The last one I had for service had lost some of it's data. The HEX editor showed that some bits went from 0 to 1. Just a few, but enough to lock the machine up by pressing the shuffle button. I had the same on a Memory Moog a few years ago. Those EPROMS got 25 years of data retention and some start to lose them now. BTW those HN61256 are mask "programmed", i.e. produced with the data already inside. No worries, they can't lose any data.
+Chip Guy Vids Thanks For that information chip guy. Its always nice go get these snippets of info added in the comments for everyone to read. Much appreciated.
How did I miss this? My fav repair channel opening one of my drum machines? :-) Edit: Oh, no, the buttons that came loose, I *did* watch this before, I just forgot. Haha! One common problem with 909's is that they behave weird and erratic or that some buttons doesn't work. That's all the flat wire contacts. Just reseating them usually does the trick for 5 more years of usage. :-)
You're like Steve Irwin but for electronic instruments! That's supposed to be a great compliment because you're obviously informed & passionate about this subject. Thanks for sharing your knowledge with us! Keep it up & don't please don't get electrocuted in the heart ;-O
I finally bought the 909 on August 23 and it arrived at my house on September 8. It was just in time for me to make a song on September 9th (9/09). The TR-909 I bought had some very noisy pots though. I used your video to figure out how to take it apart and clean it. It was great until you didn't show me how to take out the lower board. I found the screws, but I didn't realize you had to use a wrench to unscrew the battery compartment nuts. Thankfully, my wife showed me. I like it when you just fast forward through the video while you do the work so I can tell what I need to do next. Please don't take that the wrong way. I really do love your videos too. I also wanted to ask where you are from. I like your accent. :) Take care and please keep up the awesome videos. :) Sam.
Hi Sam. I'm pleased you have a 909. and you made a track on 9/09 (that was meant to happen) . I live in Brighton UK but originally come from a country village called Bakewell in derbyshire. Many Thanks from Markus
Yes they were very expensive indeed but they do hold their value quite well. I wish Roland would remake these in every way shape and form instead of the TR-8 though that is a great drum machine also.
Super awesome video! I love it. The 909 is on my wishlist, but since I just bought the 808 it'll be a while before I can get it. I really enjoyed your video. Keep up the great work. :)
Fantastic video series! Keep them coming! What's your opinion on a possible sacrilege: for those broken chassis posts, the permanent, strongest solution would be to drill through the top panel and insert a truss-head machine screw from the outside in, of the same thread as the post, with a loc washer between. It would lock the posts firmly to the chassis, maybe with a bit of threadlocker around on the inside. It could be done discretely from the outside, and the screwheads could be painted to closely match the chassis so they were almost unnoticeable. Do you think that's something customer would have gone for?
I think on a really good epoxy, like Endfest 300, the posts can stick down fine. You can possibly fill around them to provide more support. But surface preparation is super important! The white residue might be superglue, so that definitely needs to be taken off with acetone. Additionally, sanding both sides is a really good idea, and then wiping down with isopropanol. Just be careful not to get acetone on paints and PS/ABS plastic parts.
Great videos! 1 note: "Monolithic" applies to any integrated circuit. You are thinking of SIP (single in-line package), as opposed to DIP (dual in-line package).
+thesoundofphysics I thought that too ( that monolithic = IC.) I thought maybe he meant monolithic in the sense it was multiple op amps in a single package, as I was not sure op amps were generally called ICs ( but obviously is multiple components in a single package.)
+Michael Bauers Hi Michael, when I used the word Monolithic I meant the pins are only on one end and the component stands upright rather than it being flat on the board with pins down two sides.
I´ve done a clone of the snare and bass drum some ten years, because they both are the most complex analog sound sources for drums voices which you can tweak around a lot :)
thank you for this very interesting look into the 909 ! i have to open my one soon ... so now i know what me expect when i have to fix some inside. : )
Hi the POLYGIRL. theres nothing to it really, I never know what I'm doing until the video is finished and i try to polish things up afterwards as I do make some mistakes and my language sometimes when things are not going smooth certainly needs removing from the video's LOL.
hi Fabian, thanx for your asking. so, its nothing to bad on my one. just only need new stop switch, bd vol. and tempo pot replace... i think its easy to do and i got the most parts ready to repair soon. ; ) btw. the original tempo pot (or compatible one) is pretty hard to get here... phweeee
First off, before my little critique I'd like to say I enjoy these videos greatly so thanks for uploading! Cleaning old pots like that is generally not a good idea. As a professional engineer & technician I would never spray that stuff in any old carbon pots. Ideally they should be either be replaced outright or removed and disassembled one by one and cleaned with pure isopropanol. I cringe whenever I see someone using those spray cleaners. They don't work, they make the problem worse in the long run. It's a short term solution at best. I wouldn't want less experienced techs to see this video and then run out and buy spray cleaner and spray it all in a 808 or a 909 etc..
+Code Mode Yes I agree that would be the best thing to do though I was repairing this for a friend who I had already suggested replacement parts but he just wanted it sorted for the time being and did not want to pay to have hours of work and every single pot replaced. if I was getting paid for the hours of work and all the new pots then I would have replaced them all but this was a free fix with just a couple of hours to do it in.
Hi Markus, since this is the first generation 909, I think there is a zener diode on the power supply that should have been replaced! Great video though.
Thanks so much for the advice!! Looks like its screwdriver time! :-) I will film the results and let you know how I get on, its the clicky buttons so i'll have to get out the contact cleaner :-) Much respect!
Hi look for mrk1230 on youtube. there is a video on how to replace tactile switches on the mpc3000 I have not watched it yet but there may be some useful info for you. best wishes
15:53 - "Sounds OK..." I agree... I am a proud owner of a real 909 but I really enjoy the TR-8... We have two of them in our studio... Great stuff... The TR-8 I mean... Nothing beats the real deal but the new ones are sure a lot of fun...
looking at the service manual can you adjust the sound of the clap on the board when opened like this? i think so but from this vid i dont see that small pot or whatever to adjust thanks!
My 909 has the entire battery holder removed ( I bought it like that) I'm guessing that the guy who sold it to me cut the wires on the face of the mother board. I haven't pulled it apart yet, Is the connection an obvious one? Thanks for the Video - This helped a lot
Hi Raymond. The 909 was a repair job so I do not have it still here. but the battery connections were just soldered down to the board. Im not sure where they go of the top of my head but there was a schematic diagram on google. Have a search around for schematics and it should come up. Best of luck.
+JOHNNY BAGWASH Hi Johnny. I use to be a sound & lighting tech years ago, did a lot in repairs etc but now I'm sort of retired and just do these vids for a hobby really.
Hi Bestovitch, Im kinda bogged down with repairs for at least a month but let me know what you need and I will try and help out. best wishes from Markus
Fascinating! Great to see inside such a legendary bit of kit. Quick question... I have a mixer with about 3 trim pots which appear to be doing nothing when turned; could this method of cleaning be a solution to this problem? Thanks in advance. And keep up the excellent videos.
Hi Paul. yes have a go at cleaning them the same way I do. don't use too much spray though as you don't want it on the actual Posts because there is grease there. the contact cleaner costs £3.95 from marlin electronics and lasts for years. best wishes
markusfuller that's cool, I worked d it out! Anyway, did exactly what you suggested and now all channela on my old mixer work a treat. I'm very pleased! Thank you so much for your help and guidance. :)
Great video, thanx Marcus:) I would have clean the buttons und thier landings prior to glue them with 2k, because you glue may just paint/dust to the buttons... and it may won´t last very long.
Hi Tubical. no danger of glue on the buttons. I just spot glued on the weld marks on the casing then placed the posts down onto the front cover. I know it won't last for ever but the antistatic hard foam should help keep everything in place.
My instrument select button has stopped working. When I press instrument select + instrument key it won't change instruments. Any idea of what it could be and I would I go about fixing it please? Cheers
Hi fuzzybobbles. I would LOVE to get my hands on the Elka Synthex again. I repaired one almost 20 years ago and it was a monster of a machine but I always remember just how great the thing sounded. they are worth a lot of cash today. Id also like to get the CS80 Hmmmm Heaven.
markusfuller I'm currently building a laser harp and would love an Elka Synthex instead of using samples and a midi interface to my laptop. I saw Jean Michel Jarre using his laser harp and I noticed on stage he had a Synthex connected with midi and audio out and we all know why it was there and didn't actually play it using the keyboard. :-D Last time I saw a working Synthex for sale was about 6 years ago with a £6K price tag. I just wish I had a Delorean and go back to 1988 when most classic synths were either thrown out or sold for peanuts. But Deloreans are £20k so screwed both ways lol.
Hi Markus! I really enjoyed this video among many others you’ve posted :) Got a question on 909 pots; the snare volume pot on my unit is starting to feel very stiff and it’s difficult to turn it. Compared to all the other pots which feel smooth, it feels rough like it’s run out of lubricant or something. Wondering if you had any advice on what to do. You think the pot needs replacing? Also what is the best method you’ve found to remove the knobs? Thanks
hello. the poyt may be drying up so yes some lubricant could be useful or even try cleaning the pot as there could be dirt built up in there that is causing it to feel stiff. deoxit is one brand that may help but best to be sure it contains lubricant also as some pot cleaners will dissolve the lubricant. i use a credit card with a slot cut into it to slide under the pot and a couple of blades under both sides of the pot to gently try and prize it upwards. the card is to you don’t mark the surface of the 909. yes some of these caps are really difficult to remove.
Hey Markus thanks for the response! I was wondering if it would be possible to replace the tact switches on my Akai MPC2500. Some of the buttons have become unresponsive and take a firm press to register or sometimes don't register at all. Keep up the great work and videos! Kind regards Paul
Hi Bestovitch, if they are the clicky type buttons as in the numerical keypad then there maybe small metal discs under them and they are in turn stuck down with a thin plastic film over the top. you can lift them up and clean the contacts on the circuit board. if they are the rubber squishy type buttons then you could draw over the black track contacts with a very soft HB pencil as this will provide a temporary fix for a year or so then they would need doing again after that. I would be happy to try it for you but Im bogged down with work for at least a month and dare not take on any work at the moment as things would sit on my shelves for weeks before I can get around to them. but have a go yourself you may fix it and you could make a video as you go along :-) other than that if i can help through messaging I will certainly try my best.
Hi, I got one tr909 but the clap and low Tom as well as the step sequencer # 5 and # 12 doesn’t respond. Can anyone help? I still can use it and everything else works well. I would like to fix it.
Hi, Where in the UK are you? I have a Roland MKS-50 that needs repairing, as the "Enter" button doesn't work, so can't store sounds etc.Alsi the battery is soldered on a raised post, so would like a new battery holder. I looked inside to see if I could do anything, but is beyond me. If you have a website/contact details then we can discuss your rate etc.I travel the UK quite a lot, so could drop off or just post.
when you say ENTER button you mean the red WRITE button I guess ?. is it the rack mount version of the roland Juno. battery should not be a problem though you may lose your settings so would have to back things up first. I actually live in Brighton East Sussex but am so bogged down with repairs at the moment that i could not take on any more jobs for at least a month. but if you don't find anyone get back in touch with me and i will try and help. best wishes from Markus.
I need some help please. I'm wanting to move towards electronic music. I far prefer hardware as opposed to software and love the old school sounds from the 80's early 90's. Aside from the TT-303 and the TB-8 what other equipment do I require to make electronic music? What do I use to sample for instance? Some of the set ups I've seen are mind boggling so It would be good to start off with something more simple and back to basics.
+Fury 161 Hi Fury. I would start off using something like Cubase - Logic - ableton or one of the many other DAWs as they mostly all come with a few plug ins and drum machines etc to get you started. then maybe if you want to progress onto hardware instruments well There is just so many different manufacturers of amazing gear I could not really direct you towards any single maker as they all have their plus and minus's.
Hey Markus. Did you heard about the Mfb Tanzmaus? it seems to me that this little drum machine is a copy of the TR-909. I would love to see you take it apart amd have a look inside :)
Hi I looked across the electrolytics for the typical bulges etc but the machine worked fine so I did not go into an extensive service as this was just a clean up and pad the buttons. but if they ever do need replacing it belongs to a friend of mine so I would do that when the problem arises. I know some people just go ahead and replace them all now and then which can be a good thing but i only had it for a couple of days so the quick fix was all i had time for.
markusfuller Understandable,it's just that replacing these makes these older machines(over 30 years old)much more reliable and dare I say better sounding. Keep up the good work!,like your vids.
Any ideas on what may be wrong with my 909. I can't clear patterns with the clear button. Only manually while the sequencer is running. Also the scale function is no longer functioning.
Hi Markusfuller, my 909 has a problem with the RIDE sound, volume is very low and always noisy, even when not in play or pressed. Can you suggest how to fix it? Thanks
Hello there! I've been always enjoying watching your videos, but i never thought I'm gonna need your help (unfortunately for me). Since couple days my TR-909 is blinking for a couple seconds after I press the power ON, then it works fine. before even it starts blinking, there is no light at all, like it wasn't even ON. Can you please give me some hints or advice what the problem might be?
+Radiophonica Oh not too sure about that but it seems strange you should ask this just now as A friend of mine has just developed the same sounding problem with his 808 where the Leds seem to flash for a while before the thing wakes up and it has never done that before. Im hoping to get a look into it one day when he brings it around.But off the top of my head I do not know where to look. Maybe its warning you that the backup battery is dying ?. (thats just a guess)
I got my mother's old 909 and played it for a while, until the low tom stopped working. Every time I play it I hear a static white noise that doesn't fade out until I turn the level down or turn off the machine. Do you know how that can be fixed? I really don't know I could I mess that up. Overheating maybe?
to be honest Michael I just would not have the time to service one, I work full time already and find it difficult to keep on making these videos as theres not enough days in the week. theres some items here that have been under my desk for almost a year waiting for the time to fix them. sorry about that.
donthewatcher Hi the start stop button was just an old fashioned mass produced computer style switch. trouble is they are so hard to find now, It may be useful to try a multimeter across the pins of the button to see if it is working first just incase the problem is on the board somewhere else, then open the switch up and give it a good clean. I do not know of any alternatives available to buy that would match them. I would strip the button apart and try to fix that. Good luck
Hi, Im sorry but I cannot service your 909 for you, Im not always successful in repairing electronics from the vintage era as I cannot always get the parts anymore. my apologies from markus
ahhhh no you don't use switch cleaner on a drum machine worth almost £2000 its going to dissolve the grease that's supposed to be on the shafts in the short term its going to make some pots easier to turn than others and in the long term it could make the pots wobbly. either replace them all or take them apart one by one and clean them by hand.
TR-909 was that one which turned nice rich and crisp sounding drums and percussion of the 80's into crap. All the "909" remixes look like a kind of sonic marasmus comparing to the originals.
This is definitely not the way to clean scratchy pots. The very liquid contact cleaner, even when lightly sprayed, will eventually spread by capillarity everywhere inside the potentiometers cavity and dissolve the sticky silicone lubricant on the shafts, rendering the movement too easy and make all the shafts eventually wobbly. A professional repairman would take the time to desolder each pot, open it and clean the carbon trace and wipers inside with isopropanol, not contact cleaner, and re-assemble and re-solder each one carefully. This is the lazy cleaning job anybody can do, and will definitely lower the value of the device. Because if the owner ever wants to sell it, as soon as potential buyers will put their hands on the pots they will instantly know that a poor cleaning job has been done with contact cleaner, which inevitably returns to scratchiness after a short while with contact cleaner... I'm talking from experience. All that being said, I still enjoy your videos Markus because it's always interesting to see the insides of devices and what makes them tick.
That Mitsubishi EPROM is now 30 years old. The last one I had for service had lost some of it's data. The HEX editor showed that some bits went from 0 to 1. Just a few, but enough to lock the machine up by pressing the shuffle button. I had the same on a Memory Moog a few years ago. Those EPROMS got 25 years of data retention and some start to lose them now. BTW those HN61256 are mask "programmed", i.e. produced with the data already inside. No worries, they can't lose any data.
+Chip Guy Vids Thanks For that information chip guy. Its always nice go get these snippets of info added in the comments for everyone to read. Much appreciated.
Do they corrupt because some light gets to them? I used to have an oberheim prommer!
Thanks for posting all these videos... love them!!
+Oliver Chesler ThankYou Oliver
How did I miss this? My fav repair channel opening one of my drum machines? :-)
Edit: Oh, no, the buttons that came loose, I *did* watch this before, I just forgot. Haha!
One common problem with 909's is that they behave weird and erratic or that some buttons doesn't work. That's all the flat wire contacts. Just reseating them usually does the trick for 5 more years of usage. :-)
You're like Steve Irwin but for electronic instruments! That's supposed to be a great compliment because you're obviously informed & passionate about this subject. Thanks for sharing your knowledge with us! Keep it up & don't please don't get electrocuted in the heart ;-O
Hi Rahul, That is a great compliment indeed I was a Big fan of Steve Irwin.
Markus thank your for all your entertaning videos, also thanks to Jason for filming, I hope you do well guys!
Great video. I really enjoy when you open equipment and go through the components in a really easy to follow way. Keep 'em coming!
Thanks Stefan. Im on the lookout for the next video to do soon. best wishes
Mine had one breakdown 20 years ago and has been working great since. Thanks for this video! It will come in handy eventually.
+Pauly's_crates It is an amazing drum machine, I wish Roland would remake them in the old fashioned sense rather than a modern emulation.
Cheers!! Looking foward too seeing inside more synths!
I finally bought the 909 on August 23 and it arrived at my house on September 8. It was just in time for me to make a song on September 9th (9/09). The TR-909 I bought had some very noisy pots though. I used your video to figure out how to take it apart and clean it. It was great until you didn't show me how to take out the lower board. I found the screws, but I didn't realize you had to use a wrench to unscrew the battery compartment nuts. Thankfully, my wife showed me. I like it when you just fast forward through the video while you do the work so I can tell what I need to do next. Please don't take that the wrong way. I really do love your videos too. I also wanted to ask where you are from. I like your accent. :) Take care and please keep up the awesome videos. :) Sam.
Hi Sam. I'm pleased you have a 909. and you made a track on 9/09 (that was meant to happen) . I live in Brighton UK but originally come from a country village called Bakewell in derbyshire.
Many Thanks from Markus
I'd love to visit the UK someday soon. Take care and keep up the wonderful videos. :)
This brings back memories, I owned a 909 in the day. Interesting to see inside. A nice drum machine, but expensive as I remember
Yes they were very expensive indeed but they do hold their value quite well. I wish Roland would remake these in every way shape and form instead of the TR-8 though that is a great drum machine also.
Excellent repair job and an interesting look inside.
Very well presented.
First time i heard it, was on Madonna Vogue in 1990 .i love the Tr 909 👍🏽great video by the way , and u seem like a really nice chap
keep the 909's going mr marcus
Really like your videos!. Electronic teardown, information about creators and lots of cool synthesizers. What could get better? :)
Super awesome video! I love it. The 909 is on my wishlist, but since I just bought the 808 it'll be a while before I can get it. I really enjoyed your video. Keep up the great work. :)
Fantastic video series! Keep them coming!
What's your opinion on a possible sacrilege: for those broken chassis posts, the permanent, strongest solution would be to drill through the top panel and insert a truss-head machine screw from the outside in, of the same thread as the post, with a loc washer between. It would lock the posts firmly to the chassis, maybe with a bit of threadlocker around on the inside.
It could be done discretely from the outside, and the screwheads could be painted to closely match the chassis so they were almost unnoticeable.
Do you think that's something customer would have gone for?
Markus. "Sussudio" was an Oberheim DMX. "Take me home" was the 909 yes.
Great job Markus.
I think on a really good epoxy, like Endfest 300, the posts can stick down fine. You can possibly fill around them to provide more support. But surface preparation is super important! The white residue might be superglue, so that definitely needs to be taken off with acetone. Additionally, sanding both sides is a really good idea, and then wiping down with isopropanol. Just be careful not to get acetone on paints and PS/ABS plastic parts.
Great videos! 1 note: "Monolithic" applies to any integrated circuit. You are thinking of SIP (single in-line package), as opposed to DIP (dual in-line package).
+thesoundofphysics I thought that too ( that monolithic = IC.) I thought maybe he meant monolithic in the sense it was multiple op amps in a single package, as I was not sure op amps were generally called ICs ( but obviously is multiple components in a single package.)
+Michael Bauers Hi Michael, when I used the word Monolithic I meant the pins are only on one end and the component stands upright rather than it being flat on the board with pins down two sides.
thanks a lot, was a pleasure watching.
That TR looks good inside after all those years after production. PCB looks nice, no "blubber" lines on PCB...
I´ve done a clone of the snare and bass drum some ten years, because they both are the most complex analog sound sources for drums voices which you can tweak around a lot :)
thank you for this very interesting look into the 909 ! i have to open my one soon ... so now i know what me expect when i have to fix some inside. : )
Hi thePOLYGIRL, I hope you make a video when you need to fix it, I look forward to watching if you make one up. best wishes from markus
markusfuller
hi Markus : )
i dunno if i can make a vid like your's ... maybe only some photos of the repair with explanations... : )
Hi the POLYGIRL. theres nothing to it really, I never know what I'm doing until the video is finished and i try to polish things up afterwards as I do make some mistakes and my language sometimes when things are not going smooth certainly needs removing from the video's LOL.
thePOLYGIRL Whats the problem with yours ?
hi Fabian, thanx for your asking.
so, its nothing to bad on my one. just only need new stop switch, bd vol. and tempo pot replace... i think its easy to do and i got the most parts ready to repair soon. ; )
btw. the original tempo pot (or compatible one) is pretty hard to get here... phweeee
hi there. brilliant video . is that a Kenwood trio 95rds communication receiver in the corner by any chance. corner
First off, before my little critique I'd like to say I enjoy these videos greatly so thanks for uploading! Cleaning old pots like that is generally not a good idea. As a professional engineer & technician I would never spray that stuff in any old carbon pots. Ideally they should be either be replaced outright or removed and disassembled one by one and cleaned with pure isopropanol. I cringe whenever I see someone using those spray cleaners. They don't work, they make the problem worse in the long run. It's a short term solution at best. I wouldn't want less experienced techs to see this video and then run out and buy spray cleaner and spray it all in a 808 or a 909 etc..
+Code Mode Yes I agree that would be the best thing to do though I was repairing this for a friend who I had already suggested replacement parts but he just wanted it sorted for the time being and did not want to pay to have hours of work and every single pot replaced. if I was getting paid for the hours of work and all the new pots then I would have replaced them all but this was a free fix with just a couple of hours to do it in.
Hi Markus, since this is the first generation 909, I think there is a zener diode on the power supply that should have been replaced! Great video though.
Thanks Mike.
Love your video's and your passion :)
Thanks. This was really helpful. I needed to open mine up to repair the ride circuit. Is that Groove Armadas machine? I recognise that rhythm track.
Thankyou samricemonkey Im pleased you got yours repaired. I cannot remember who owned this one in the video as it was a long time ago.
Thanks so much for the advice!! Looks like its screwdriver time! :-) I will film the results and let you know how I get on, its the clicky buttons so i'll have to get out the contact cleaner :-)
Much respect!
Hi look for mrk1230 on youtube. there is a video on how to replace tactile switches on the mpc3000 I have not watched it yet but there may be some useful info for you. best wishes
was that the roland demo song that plays when you reset the instrument?
15:53 - "Sounds OK..." I agree... I am a proud owner of a real 909 but I really enjoy the TR-8... We have two of them in our studio... Great stuff... The TR-8 I mean... Nothing beats the real deal but the new ones are sure a lot of fun...
Hello Roland marketing intern
looking at the service manual can you adjust the sound of the clap on the board when opened like this? i think so but from this vid i dont see that small pot or whatever to adjust thanks!
Wow great video!
cool vid, thanks for sharing
My 909 has the entire battery holder removed ( I bought it like that) I'm guessing that the guy who sold it to me cut the wires on the face of the mother board. I haven't pulled it apart yet, Is the connection an obvious one?
Thanks for the Video - This helped a lot
Hi Raymond. The 909 was a repair job so I do not have it still here. but the battery connections were just soldered down to the board. Im not sure where they go of the top of my head but there was a schematic diagram on google. Have a search around for schematics and it should come up. Best of luck.
Mnatronix Mantronix - Bassline used this
... And Schooly Ds first album
MIDI In, Out, Thru? This must have been one of the first drum machines with MIDI then.
love the videos what does mr marcus do as a living do you repair things as a business
+JOHNNY BAGWASH Hi Johnny. I use to be a sound & lighting tech years ago, did a lot in repairs etc but now I'm sort of retired and just do these vids for a hobby really.
just been curious love the 909 repair I own the holy grail a brand new 909 boxed with 5 hr use
Great video Markus! How does one go about enlisting your services?
Hi Bestovitch, Im kinda bogged down with repairs for at least a month but let me know what you need and I will try and help out. best wishes from Markus
Fascinating! Great to see inside such a legendary bit of kit. Quick question...
I have a mixer with about 3 trim pots which appear to be doing nothing when turned; could this method of cleaning be a solution to this problem? Thanks in advance. And keep up the excellent videos.
Hi Paul. yes have a go at cleaning them the same way I do. don't use too much spray though as you don't want it on the actual Posts because there is grease there. the contact cleaner costs £3.95 from marlin electronics and lasts for years. best wishes
sorry i meant maplin electronics . the computer tried to correct my spelling as marlin ?.
markusfuller that's cool, I worked d it out! Anyway, did exactly what you suggested and now all channela on my old mixer work a treat. I'm very pleased! Thank you so much for your help and guidance. :)
Great video, thanx Marcus:)
I would have clean the buttons und thier landings prior to glue them with 2k, because you glue may just paint/dust to the buttons... and it may won´t last very long.
Hi Tubical. no danger of glue on the buttons. I just spot glued on the weld marks on the casing then placed the posts down onto the front cover. I know it won't last for ever but the antistatic hard foam should help keep everything in place.
Great video! Thx for sharing!
My instrument select button has stopped working. When I press instrument select + instrument key it won't change instruments. Any idea of what it could be and I would I go about fixing it please? Cheers
Always enjoy your videos when it comes to proper synths. One day I hope you'll get your hands on an Elka Synthex and let us see inside it. :o)
Hi fuzzybobbles. I would LOVE to get my hands on the Elka Synthex again. I repaired one almost 20 years ago and it was a monster of a machine but I always remember just how great the thing sounded. they are worth a lot of cash today. Id also like to get the CS80 Hmmmm Heaven.
markusfuller I'm currently building a laser harp and would love an Elka Synthex instead of using samples and a midi interface to my laptop. I saw Jean Michel Jarre using his laser harp and I noticed on stage he had a Synthex connected with midi and audio out and we all know why it was there and didn't actually play it using the keyboard. :-D
Last time I saw a working Synthex for sale was about 6 years ago with a £6K price tag. I just wish I had a Delorean and go back to 1988 when most classic synths were either thrown out or sold for peanuts. But Deloreans are £20k so screwed both ways lol.
Hi Markus! I really enjoyed this video among many others you’ve posted :) Got a question on 909 pots; the snare volume pot on my unit is starting to feel very stiff and it’s difficult to turn it. Compared to all the other pots which feel smooth, it feels rough like it’s run out of lubricant or something. Wondering if you had any advice on what to do. You think the pot needs replacing? Also what is the best method you’ve found to remove the knobs? Thanks
hello. the poyt may be drying up so yes some lubricant could be useful or even try cleaning the pot as there could be dirt built up in there that is causing it to feel stiff. deoxit is one brand that may help but best to be sure it contains lubricant also as some pot cleaners will dissolve the lubricant. i use a credit card with a slot cut into it to slide under the pot and a couple of blades under both sides of the pot to gently try and prize it upwards. the card is to you don’t mark the surface of the 909. yes some of these caps are really difficult to remove.
I am in the exact situation. buttons are pressing the board down. Safe to follow this and try? I mean its $3000 rig now. slightly worried.
You are The Best !
Hey Markus thanks for the response! I was wondering if it would be possible to replace the tact switches on my Akai MPC2500. Some of the buttons have become unresponsive and take a firm press to register or sometimes don't register at all.
Keep up the great work and videos!
Kind regards
Paul
Hi Bestovitch, if they are the clicky type buttons as in the numerical keypad then there maybe small metal discs under them and they are in turn stuck down with a thin plastic film over the top. you can lift them up and clean the contacts on the circuit board. if they are the rubber squishy type buttons then you could draw over the black track contacts with a very soft HB pencil as this will provide a temporary fix for a year or so then they would need doing again after that. I would be happy to try it for you but Im bogged down with work for at least a month and dare not take on any work at the moment as things would sit on my shelves for weeks before I can get around to them. but have a go yourself you may fix it and you could make a video as you go along :-)
other than that if i can help through messaging I will certainly try my best.
Hi, I got one tr909 but the clap and low Tom as well as the step sequencer # 5 and # 12 doesn’t respond. Can anyone help? I still can use it and everything else works well. I would like to fix it.
Hi,
Where in the UK are you? I have a Roland MKS-50 that needs repairing, as the "Enter" button doesn't work, so can't store sounds etc.Alsi the battery is soldered on a raised post, so would like a new battery holder. I looked inside to see if I could do anything, but is beyond me. If you have a website/contact details then we can discuss your rate etc.I travel the UK quite a lot, so could drop off or just post.
when you say ENTER button you mean the red WRITE button I guess ?. is it the rack mount version of the roland Juno. battery should not be a problem though you may lose your settings so would have to back things up first.
I actually live in Brighton East Sussex but am so bogged down with repairs at the moment that i could not take on any more jobs for at least a month. but if you don't find anyone get back in touch with me and i will try and help. best wishes from Markus.
top stuff love your work its an art analog repair
I need some help please. I'm wanting to move towards electronic music. I far prefer hardware as opposed to software and love the old school sounds from the 80's early 90's. Aside from the TT-303 and the TB-8 what other equipment do I require to make electronic music? What do I use to sample for instance? Some of the set ups I've seen are mind boggling so It would be good to start off with something more simple and back to basics.
+Fury 161 Hi Fury. I would start off using something like Cubase - Logic - ableton or one of the many other DAWs as they mostly all come with a few plug ins and drum machines etc to get you started. then maybe if you want to progress onto hardware instruments well There is just so many different manufacturers of amazing gear I could not really direct you towards any single maker as they all have their plus and minus's.
Hey Markus. Did you heard about the Mfb Tanzmaus? it seems to me that this little drum machine is a copy of the TR-909. I would love to see you take it apart amd have a look inside :)
hi Adriano. If i get my hands on one I too would like to see the inner workings.
I never knew the hats were samples!
Nice repair.
How about replacing electrolytics in the future?
Hi I looked across the electrolytics for the typical bulges etc but the machine worked fine so I did not go into an extensive service as this was just a clean up and pad the buttons. but if they ever do need replacing it belongs to a friend of mine so I would do that when the problem arises. I know some people just go ahead and replace them all now and then which can be a good thing but i only had it for a couple of days so the quick fix was all i had time for.
markusfuller
Understandable,it's just that replacing these makes these older machines(over 30 years old)much more reliable and dare I say better sounding.
Keep up the good work!,like your vids.
11:17 are those pattern mechanical spring switches? Like IBM M keyboard type?
I am not sure to be honest but they do feel very similar.
Any ideas on what may be wrong with my 909. I can't clear patterns with the clear button. Only manually while the sequencer is running. Also the scale function is no longer functioning.
+303monkey To Be honest I really do not know why you are having that problem with your 909. Im sorry I cannot help there, my apologies from Markus.
Is this Richard H Kirk's 909 ? The pattern you play sounds very much late Cabaret Voltaire. ( Percussion Force ) :0
Hi no this is not richards 909.
@@markusfuller Thanks Markus !
Does it have Overbridge?
fan-tastic!
Hi Markusfuller, my 909 has a problem with the RIDE sound, volume is very low and always noisy, even when not in play or pressed. Can you suggest how to fix it?
Thanks
I fix it, replacing filter transistor ! :D
Hello there!
I've been always enjoying watching your videos, but i never thought I'm gonna need your help (unfortunately for me).
Since couple days my TR-909 is blinking for a couple seconds after I press the power ON, then it works fine. before even it starts blinking, there is no light at all, like it wasn't even ON.
Can you please give me some hints or advice what the problem might be?
+Radiophonica Oh not too sure about that but it seems strange you should ask this just now as A friend of mine has just developed the same sounding problem with his 808 where the Leds seem to flash for a while before the thing wakes up and it has never done that before. Im hoping to get a look into it one day when he brings it around.But off the top of my head I do not know where to look. Maybe its warning you that the backup battery is dying ?. (thats just a guess)
I got my mother's old 909 and played it for a while, until the low tom stopped working. Every time I play it I hear a static white noise that doesn't fade out until I turn the level down or turn off the machine. Do you know how that can be fixed? I really don't know I could I mess that up. Overheating maybe?
could be a transistor needs replacing in the tom circuit? I have the same problem with the ride and am in the process of fixing it.
can anyone tell me reasons a 909 won't power on even though the PSU is working fine?
what are those green glossy components?, i've seen lots of them in mks-80
Hello, those green glossy components are capacitors.
such a sexy machine!
Fascinating, Cheers. :)
do TR 606 or 707 when you get the chance please!
Hi Michael. If I get my hands on one I will certainly make a video. many thanks from markus
Sounds great! Out of interest, would you repair/service one if I got one that required some work?
to be honest Michael I just would not have the time to service one, I work full time already and find it difficult to keep on making these videos as theres not enough days in the week. theres some items here that have been under my desk for almost a year waiting for the time to fix them. sorry about that.
my 909 won't turn on. Can you tell me why?
Yes.
GOOD ON YA!!!!!!
hi mark any tips on fxing my roland tr 808 start and stop button (doesn't work)
donthewatcher Hi the start stop button was just an old fashioned mass produced computer style switch. trouble is they are so hard to find now, It may be useful to try a multimeter across the pins of the button to see if it is working first just incase the problem is on the board somewhere else, then open the switch up and give it a good clean. I do not know of any alternatives available to buy that would match them. I would strip the button apart and try to fix that. Good luck
True with a little patience and care you can disassemble the buttons and clean the inner parts.
hello mate,i am based up in scotland,would you service my 909 as well,and if you do so,how much would it be?
:)
Hi, Im sorry but I cannot service your 909 for you, Im not always successful in repairing electronics from the vintage era as I cannot always get the parts anymore. my apologies from markus
no brother mate,i thought its worth a try tho :) never mind
Nice!!
Great!
ahhhh no you don't use switch cleaner on a drum machine worth almost £2000 its going to dissolve the grease that's supposed to be on the shafts in the short term its going to make some pots easier to turn than others and in the long term it could make the pots wobbly. either replace them all or take them apart one by one and clean them by hand.
Thats why you change them with new ones ,
not clean them .
Is the foam you added prone to "foam rot"?
maurice fitzmaurice I guess all Foam rots eventually.
What a sexy machine
Thumbs Up!
TR-909 was that one which turned nice rich and crisp sounding drums and percussion of the 80's into crap. All the "909" remixes look like a kind of sonic marasmus comparing to the originals.
beatles sang "one after 909 "
The lost brother of ColinFurze?
Lots of weird Japanese chips 🤔
This is definitely not the way to clean scratchy pots. The very liquid contact cleaner, even when lightly sprayed, will eventually spread by capillarity everywhere inside the potentiometers cavity and dissolve the sticky silicone lubricant on the shafts, rendering the movement too easy and make all the shafts eventually wobbly. A professional repairman would take the time to desolder each pot, open it and clean the carbon trace and wipers inside with isopropanol, not contact cleaner, and re-assemble and re-solder each one carefully. This is the lazy cleaning job anybody can do, and will definitely lower the value of the device. Because if the owner ever wants to sell it, as soon as potential buyers will put their hands on the pots they will instantly know that a poor cleaning job has been done with contact cleaner, which inevitably returns to scratchiness after a short while with contact cleaner... I'm talking from experience.
All that being said, I still enjoy your videos Markus because it's always interesting to see the insides of devices and what makes them tick.
Do you have a video, showing you repairing and restoring a 909? Because talk is cheap...