606 problems!

[Twinfield]

Hi everyone,

My 606 has decided it no longer wants to work. basically when I switched it on yesterday it started randomly playing sounds. I've tested in on both PSU and batteries, but both yeild the same results. I emailed a very nice guy at a synth repair company in the UK who said that if the batteries are removed or go flat it can scramble the patterns, he suggested I put a fresh set of batteries in, clear the patterns and start over. I have tried that but to no avail. I have linked a video of what is currently happening down below. Can anyone help? I need my little machine up and running again! Power transistor? I'm not very good at diegnosing problems, but am more than capable with a soldering iron.




Thanks.

[Rayek]

Looks like a dead/misfiring CPU to me. I'm not sure what else it would be... I'd caution against swapping it, what caused yours to fail might cause a new one to fail as well.

Unfortunately, I have one extra but it is also dead (a swap to the quicksilver 606 CPU and recapping the power supply fixed my 606).

[Twinfield]

Hi Rayek, thanks for you reply. I'm not 100% convinced it's the CPU, wouldn't the sequencer and function buttons fail to work if that was the case? Some of the sounds are still playing fine, they are just massively jumbled up, there is also a constant 'sss' noise that sounds like the cymbal is misfiring over and over. A guy over on another forum suggested that the "digital section could need reflowing"?

[Twinfield]

I've managed to fix the problem myself. Dodgy sync switch. A bit of switch cleaner, a reflow and some wiggling and it is a working again now! very odd!

[Twinfield]

Unfotunatly the issue has returned. It has been working intermittently. It would play a pattern completely fine and then after about 10 minutes it would decide to go crazy again, acting exactly the same as in the video i posted in the first post. Does anyone have any ideas?

[jxalex]

Unfotunatly the issue has returned. It has been working intermittently. It would play a pattern completely fine and then after about 10 minutes it would decide to go crazy again, acting exactly the same as in the video i posted in the first post. Does anyone have any ideas?

Thats not bad in this case. May be loose connection or solder joint.

reseat the connectors, clean again. All potentiometers and switches. couple drops of WD40 and SAE5-50 oil will do fine. check the cabling, oxide in connectors.

also in time the solder joints may give up (for example my Juno-106 went blank occassionally once it got warm and I had to BEND it on its sides so it would power up again. The error was fixed by resoldering the joints. )

* Knock with a plastic hammer lightly on circuit boards and details if to see something triggers that fault.

* overheating? are there some details which are too hot to touch (over 50C TEMPERATURE?)

ALSO, not all capacitors go bad. So there is no need for panically swapping capacitors. In fact the new ones may go wrong sooner than we think, as we know todays loose manufacturing standards...

[Twinfield]

Thanks for the help. I'll have another look at it tomorrow and let you know. I'm sure it's something small I'm missing, that's why I'm reluctant to pay to get it serviced.

It's curretly playing hihats fine. All other instuments are constantly triggering though

[Twinfield]

Here's an update video.

I got it to work this morning for about 10 seconds before it went again. I've reflowed all the cables that connect the switch board to the main board. Ive also cleaned all switches an penetrometers again with servisol. Hi hats work ok in some modes but not all, everything else is still playing up.

[d2mrp0]

I have a 606 and it has worked well since 1982. But it only works on batteries. I used to have a TB 303 that would work intermittently, and it was found to be a hairline crack in one of the circuit board tracks. You need a very good magnifying lens, lots of patience, and a very bright lamp strapped to your head. Your 606 problems do sound like a cracked track or something loose inside. The fact that it did work only for a few seconds is encouraging.