Roland SH3a - noisy pots and keyboard - Help!

[outbackyak]

So, I've had this SH3a for about 25 years, and it's spent the last 15 in storage. Pulled it out the other day, and it needs some loving care. Many of the pots and sliders are very noisy, crackling and sputtering. You can't get a smooth cutoff or resonance sweep, as they sort of jump from one level to the next. Similar with the LFO rate sliders.

In addition, some of the keys are dodgy - I get audio clicks from them, they sometimes retrigger the same note, or fail to trigger a note at all.

I'm presuming that this is all caused by dirty pots and contacts, and that it is possible to fix it by using some sort of spray contact cleaner. But I know nothing about repairing electronic equipment, so ...

1. Is my diagnosis correct - is it just a matter of cleaning the relevant pots, contacts, etc?

2. If so, what is the best product for cleaning the pots and contacts?

3. Can anyone give me step by step instructions on the best way to do it, or point me to a good guide for how to do it?

4. Am I insane to think of trying to do this myself?

5. Oh, and the relative keyboard tuning seems to have slipped (i.e. C3 is slightly out of tune with C4 and so on). Is there an easy way to adjust the individual tuning of each keyboard note?

Any assistance will be gratefully received

Cheers,

[sam]

You should first clean the key contacts. Take off the top black panel.

Underneath you can see screws that hold the keyboard in place.

Unscrew these and you can pop the keyboard up.

Spray contact cleaner on cotton buds and clean the contacts...You can also use soft wire wool.

Sometimes you have to take pots apart to clean...Try this though..

Get a cotton bud and squeeze the tip with pliers ..So it can fit into the gap of the slider.
Spray contact cleaner on the CB..And gently clean the pot.
Lift the dirt out and see if it improves...?

[outbackyak]

Thanks for that info, Sam - sounds doable, and the way I figure it I'm unlikely to make it worse than it currently is (which is just about unuseable).

Any suggestions for a good make of circuit cleaner, (or any bad ones to avoid)?

Cheers,

[Hybrid88]

Ok, This is unfortunately a very common mistake, firstly please avoid using contact cleaner on pots at all costs unless you re-grease every one you clean. Why? - well when you use contact cleaner it strips not only the dirt but also the vital grease that the pot needs to keep working. Should be fine on the keyboard contacts though as they don't need lubrication.

Try the products from CAIG Labs, these are specifically formulated for this reason, they are the best recommended for pro audio use and come in various types and forms, I've listed two types - the spray and bottle/buds - in Aus you can get it here:

http://www.jaycar.com.au/productView.asp?ID=NS1436&CATID=16&form=CAT&SUBCATID=277



And here...

http://www.jaycar.com.au/productView.asp?ID=NS1434&CATID=16&form=CAT&SUBCATID=277




Too easy, this should get your Roland up and making strange noises again (not crackling)

Cheers mate

[outbackyak]

Thanks, Hybrid88 - down to Jaycar it is, then. Yeah, I saw elsewhere that you had to lubricate the pots as well as clean them, so this looks like the best way to do both.

Cheers,