MF#21 ROLAND TR-909 look inside and repair service 

Thanks for posting all these videos... love them!!

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

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.

Mine had one breakdown 20 years ago and has been working great since. Thanks for this video! It will come in handy eventually.

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. :-)

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!

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. :)

Excellent repair job and an interesting look inside. Very well presented.

Cheers!! Looking foward too seeing inside more synths!

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

Love your video's and your passion :)

Great job Markus.

thanks a lot, was a pleasure watching.

Really like your videos!. Electronic teardown, information about creators and lots of cool synthesizers. What could get better? :)

This brings back memories, I owned a 909 in the day. Interesting to see inside. A nice drum machine, but expensive as I remember

Wow great video!

keep the 909's going mr marcus

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.

Great video! Thx for sharing!

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?

cool vid, thanks for sharing

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 :)

You are The Best !

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.

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!

That TR looks good inside after all those years after production. PCB looks nice, no "blubber" lines on PCB...

was that the roland demo song that plays when you reset the instrument?

Markus. "Sussudio" was an Oberheim DMX. "Take me home" was the 909 yes.

Fascinating, Cheers. :)

hi there. brilliant video . is that a Kenwood trio 95rds communication receiver in the corner by any chance. corner

top stuff love your work its an art analog repair

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.

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

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.

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. : )

fan-tastic!

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

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.

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

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).

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

GOOD ON YA!!!!!!

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.

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?

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..

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?

Great video Markus! How does one go about enlisting your services?

Nice!!

Does it have Overbridge?

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

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 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.

Great!

11:17 are those pattern mechanical spring switches? Like IBM M keyboard type?

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.

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.

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.

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.

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)

such a sexy machine!

MIDI In, Out, Thru? This must have been one of the first drum machines with MIDI then.

Thumbs Up!

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

my 909 won't turn on. Can you tell me why?

Is the foam you added prone to "foam rot"?

hi mark any tips on fxing my roland tr 808 start and stop button (doesn't work)

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 :)

love the videos what does mr marcus do as a living do you repair things as a business

I never knew the hats were samples!

What a sexy machine

Mnatronix Mantronix - Bassline used this

Is this Richard H Kirk's 909 ? The pattern you play sounds very much late Cabaret Voltaire. ( Percussion Force ) :0

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? :)

Nice repair. How about replacing electrolytics in the future?

do TR 606 or 707 when you get the chance please!

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.

beatles sang "one after 909 "

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.

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...

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.