Date: Sun, 24 Sep 1995 10:22:46 -0700 (PDT) From: MACHINE MEDIA Subject: Buttons I wrote to Robin Whittle about the 303 (and other Roland and Korg, etc.) buttons. This is what he sent back. He said it would be OK to post this to the list. ---------- Forwarded message ---------- Date: Mon, 25 Sep 1995 02:39:53 +0000 From: Robin Whittle To: MACHINE MEDIA Subject: Re: Switch Cleaning Advice Requested Dear Mark, Thanks for your email. The RWI proprietary method of dealing with dirty switches is to desolder them, throw them in the bin and install new ones. Then I have two techniques to minimise the contamination of the new switches: 1 - I make a sheet of polyester (or polypropylene which is softer) drafting film (matte finish plastic film for technical drawings) and install this between the switches and the buttons. This involves a 1/4" hole being punched for every switch stem and LED. To do this I have a drilling template so I can drill 1mm pilot holes into about ten sheets of plastic. Then I have a specially modified hole punch with an alignment pin so I can punch the holes in exactly the right place. This is all tricky, and sometimes I have to place a few cuts in the plastic after I put the buttons back on - so there is no tension on the switches. This will quite effectively keep most of the dust away from the switches. It can be done with paper - make a template and photocopy it so the marks on the photocopy tell you exactly where to punch the holes. 2 - I tell the customer never to leave the machine lying around - always cover it with a clean cloth or similar. The switches can be obtained fairly cheaply from your local supplier who imports the fabulous ALPS switches from Japan. (The pots and rotary switches are also from ALPS, but the pots have not been produced for years and so must be obtained from Roland.) The switches are called SKHCAA. They are black - or nearly so. There is also a dark grey model with a 260 gram force (instead of the SKHCAA's 130 gm) It is the SKHCAC, but I have never used them. The model without the stem is the SKHCAB. These are used in the TR-808 - where dust is also a problem, and the JP-8. There is nothing wrong with the switches. The original DX7 has lots of SKHCAA's but they usually work forever since they are not exposed to dust. (Check these numbers with your supplier.) I have an ALPS catalogue from 1993 and it lists the North American head-office as Ph (408)432 6000 Fax (408) 432 6035. I am not on Analogue Heaven - it was too busy for me. Post this material there if you think it is of interest. I am sorry about the delay in doing more Devil Fish mods. As soon as I am ready I will post to the list. I recently got a letter from a bloke in Paris enquiring about the Devil Fish: "I think we are wrong with our nuclear tests, but your TB-303 is a a deadly weapon too!" I will duly inform him that a DF test program is essential for national security - to assure performance, reliability and safety. All tests will be performed deep within a stable basalt structure in a remote area of Australia. Seismographic monitoring will confirm adherance to the 100 kiloton treaty limit. I have been working on something digital - improvements to the Csound program which can be used for direct music synthesis on a reasonably powerful PC or Mac. It is very different from turning knobs - and you have to wait a while for the sound to compute. There are other problems with high frequencies aliasing down into the audible range. None of these are problems in the analogue world - like "virtual reality" the anomalies and simplistic aspects help you realise what you like about the natural world. However there are some amazing things you can do with it - if you are patient and into computer programming. There is a Csound mailing list. The program and its source are freely available - see http://www.leeds.ac.uk/music/Man/c_front.html See my WWW site for my additions and documentation. It was a good idea to use both my email addresses. firstpr@ozemail.com.au is the one I use primarily now. > I wish you the very best of luck in all your endevours and continued success > with your Devilfish mods. Thanks! > Before I close it up, I plan on > installing a Kenton mod (almost finished :) and installing several other > modifications of my own design. I would be happy to share these > modifications with you. I am not looking to obtain the secrets of the > Devilfish. I agree with you in that it is much more interesting if > people develop their own modifications. I would be interested in knowing what you mods you have devised - it is more interesting to figure things out freshly. Be careful where you test that thing! Cheers - Robin . Robin Whittle . . http://www.ozemail.com.au/~firstpr firstpr@ozemail.com.au . . 11 Miller St. Heidelberg Heights 3081 Melbourne Australia . . Ph +61-3-9459-2889 Fax +61-3-9458-1736 . . Consumer advocacy in telecommunications, especially privacy . . . . First Principles - Research and expression - music, . . music industry, telecommunications . . human factors in technology adoption. . . . Real World Interfaces - Hardware and software, especially . . for music .