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"Gareth Magennis" <sound.service@btconnect.com>: Jan 14 11:01PM Hi,   I have a very old synthesiser where the top panel rubber contact switches no longer work, because the owner has removed the contact strips.   This is the synth: http://www.vintagesynth.com/sci/stk.php     The contact rubbers are pretty much 10cm x 10cm x 10cm cubes, but they have a rather large contact footprint. The corresponding PCB contact gap between the two lands that need to be bridged is also rather large. http://tinypic.com/r/14xdmo3/9       So, I am looking into the possibility of replacing the missing buttons by cannibalising a somewhat more contemporary keypad that has extra large contacts.   Here's a typical example I found at Farnell. It might be possible to cut it up and glue it to the keyboard and make things work, if the contacts are large enough. http://uk.farnell.com/storm-interface/70160101/keypad-storm-700-16way-grey/dp/9810064       Anyone any such experience here?   I know it's a long shot.       Cheers,     Gareth.

Jeff Liebermann <jeffl@cruzio.com>: Jan 14 05:11PM -0800 On Thu, 14 Jan 2016 23:01:20 -0000, "Gareth Magennis"   >Anyone any such experience here? >I know it's a long shot.   Google for "mold your own rubber parts" or "cast your own rubber parts". Lots of lousy videos on YouTube on how to mold rubber parts. I use Plaster of Paris for the mold, Devcon Flexane 94 Liquid 15250 two part urethane rubber <http://www.devcon.com/products/products.cfm?family=Flexane%C2%AE%2094%20Liquid> <http://www.amazon.com/Devcon-15250-Black-Flexane-Liquid/dp/B00065TLJK> and Vaseline or silicon grease for mold release. Careful when storing the stuff as the stuff in the bottle attacks the bottle and causes it to leak. It cures in 10-15 mins, so be prepared to work fast. Although it's made for making flex molds, it's also the right stuff for making fairly hard rubber buttons, gaskets, shock mounts, seals, etc.   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Jeff Liebermann <jeffl@cruzio.com>: Jan 14 05:28PM -0800 On Thu, 14 Jan 2016 17:11:25 -0800, Jeff Liebermann <jeffl@cruzio.com> wrote:   ><sound.service@btconnect.com> wrote:   >>Anyone any such experience here? >>I know it's a long shot.   Maybe a kit would be better than doing it from scratch: <http://www.alumilite.com> (I haven't tried these). -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Kaz Kylheku <kaz@kylheku.com>: Jan 15 02:56AM > parts". Lots of lousy videos on YouTube on how to mold rubber parts. > I use Plaster of Paris for the mold, Devcon Flexane 94 Liquid 15250 > two part urethane rubber   The resin part of this evidently contains some isocyanate monomers; careful with that! :)

Jeff Liebermann <jeffl@cruzio.com>: Jan 14 07:56PM -0800 On Fri, 15 Jan 2016 02:56:51 +0000 (UTC), Kaz Kylheku >> two part urethane rubber   >The resin part of this evidently contains some isocyanate monomers; >careful with that! :)   Beware the smell of bitter almonds (apologies to Sherlock Holmes): <http://news.wustl.edu/news/Pages/20916.aspx> I've smelled them while plating some copper PCB edge connectors with electroless silver, which is basically silver cyanide. When I tasted the rotten almonds, I was already in a stupor and had to be dragged from the building for some fresh air. I've worked with Flexane 94 a few times and survived. Wear gloves and don't inhale the vapors: <http://www.actiocms.com/VIEW_MSDS/view_language_kits2.cfm?edit_msds_id=4328&dbname=production&language=1&format=16&CFID=11369918&CFTOKEN=1c713f7731a98b98-A229D917-9DA3-18D9-6BC94692623356A2> At 10-20% of solution by weight, it's not going to be very potent.     -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Clifford Heath <no.spam@please.net>: Jan 15 02:23PM +1100 On 15/01/16 13:56, Kaz Kylheku wrote: >> two part urethane rubber   > The resin part of this evidently contains some isocyanate monomers; > careful with that! :)   As do most polyurethanes, including PU varnish, where it acts as a moisture-triggered catalyst for polymerisation. I don't think these have much to do with Jeff's cyanide experience; the main worry is allergic sensitization.

Clifford Heath <no.spam@please.net>: Jan 15 02:24PM +1100 On 15/01/16 12:11, Jeff Liebermann wrote: > Although it's made for making flex molds, it's also the right stuff > for making fairly hard rubber buttons, gaskets, shock mounts, seals, > etc.   It's a good idea to de-air the mix in a vacuum flash for a while after mixing. It's amazing how much air gets in - until you see the bubbles magically appear as you apply vacuum it's hard to believe.

N_Cook <diverse@tcp.co.uk>: Jan 15 08:24AM On 14/01/2016 23:01, Gareth Magennis wrote:   > Gareth.   What is the minimum resistance/mm of gap required?

MJC <gravity@mjcoon.plus.com>: Jan 15 08:29AM In article <5cqg9bh5gv5vnfdgt8dq7gn1clv2sfetm9@4ax.com>, jeffl@cruzio.com says...   > Beware the smell of bitter almonds (apologies to Sherlock Holmes):   Sounds like you would not want to be under the influence of a "seven percent solution" at the same time!   Mike.

mike <ham789@netzero.net>: Jan 15 12:55AM -0800 On 1/14/2016 3:01 PM, Gareth Magennis wrote:   > Cheers,   > Gareth.   I'm having a hard time reconciling your text with your picture. Looks more like 1cm cubes? And the contact is the circular spot on the bottom of the key? Rather large??? What part got removed by the customer?   I've had some success with very thin tinfoil glued to the bottom of the conductive pad on the key. But, I've not worried about longevity of the fix. Not sure that would be a good thing for a paid repair for a customer.   I did try conductive silver paint, but that flaked off rather quickly.   Also need to clean the pads on the board well, without scraping off the black conductor.   Another thing I thought about trying was a piece of "zebra strip" used to connect calculator boards to their display. Lay it sideways and properly oriented, because you need a long conductive path to connect the pads on the board.

"Gareth Magennis" <sound.service@btconnect.com>: Jan 15 09:11AM "Jeff Liebermann" wrote in message news:gvgg9bdishpmu7lsmjm7kenvjqkhh73sr9@4ax.com...   On Thu, 14 Jan 2016 23:01:20 -0000, "Gareth Magennis"   >Anyone any such experience here? >I know it's a long shot.   Google for "mold your own rubber parts" or "cast your own rubber parts". Lots of lousy videos on YouTube on how to mold rubber parts. I use Plaster of Paris for the mold, Devcon Flexane 94 Liquid 15250 two part urethane rubber <http://www.devcon.com/products/products.cfm?family=Flexane%C2%AE%2094%20Liquid> <http://www.amazon.com/Devcon-15250-Black-Flexane-Liquid/dp/B00065TLJK> and Vaseline or silicon grease for mold release. Careful when storing the stuff as the stuff in the bottle attacks the bottle and causes it to leak. It cures in 10-15 mins, so be prepared to work fast. Although it's made for making flex molds, it's also the right stuff for making fairly hard rubber buttons, gaskets, shock mounts, seals, etc.   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558   ---     Thanks, might give that a go.   Is there a tried and trusted way of adding a conductive contact pad?     Cheers,     Gareth.

"Gareth Magennis" <sound.service@btconnect.com>: Jan 15 09:17AM I'm having a hard time reconciling your text with your picture. Looks more like 1cm cubes? And the contact is the circular spot on the bottom of the key? Rather large??? What part got removed by the customer?             Sorry, that's a typo, that should be 10mm x 10mm x 10mm cubes, as the ruler in the photo shows. That same photo with the ruler shows the round pad to be about 5mm diameter, much larger than the key contact strips and button pads I find on contemporary equipment. This is old school manufacturing.         Gareth.

"Gareth Magennis" <sound.service@btconnect.com>: Jan 15 09:22AM I'm having a hard time reconciling your text with your picture. Looks more like 1cm cubes? And the contact is the circular spot on the bottom of the key? Rather large??? What part got removed by the customer?               The customer has ripped out all the contact buttons on the right side of the keyboard, the left side set is still in place and working. The photo shows the right hand side of the PCB with 2 buttons from the left side put in the photo to show the size of things.       Gareth.

mike <ham789@netzero.net>: Jan 15 02:46AM -0800 On 1/15/2016 1:22 AM, Gareth Magennis wrote: > The photo shows the right hand side of the PCB with 2 buttons from the > left side put in the photo to show the size of things.   > Gareth. OK, I can't imagine you can manufacture new keys at a repair price the customer could tolerate.   There's a guy who shows up at local ham radio swapmeets and sells radio attachment gizmos. He has a 3D printer and claims to be willing and able to make custom gizmos. I never asked the price. All his samples were rigid. Unknown whether he could make the bottom section springy enough to effect a pushbutton spring.

avagadro7@gmail.com: Jan 15 05:53AM -0800 I have a stupid question.....are keyboards connected to a connector ? is there an assembly area into the registering circuit ?

Jeff Liebermann <jeffl@cruzio.com>: Jan 15 08:31AM -0800 On Fri, 15 Jan 2016 09:11:00 -0000, "Gareth Magennis"   >Is there a tried and trusted way of adding a conductive contact pad?   Search for a rubber keypad repair kit: <http://www.amazon.com/MG-Chemicals-8339-Rubber-Keypad/dp/B0081SGM8M> <http://www.amazon.com/Keypad-Restore-Conductivity-Carbon-Copper/dp/B0026PRMVM> <http://www.amazon.com/Caig-BCG327782-Caikote-44-Kit/dp/B00E1QYYC4> <http://www.mcmelectronics.com/product/CAIG-LABORATORIES-K-CK44-G-/200-315> <http://www.ebay.com/bhp/keypad-repair-kit> <http://www.ebay.com/bhp/keypad-fix> There are videos on YouTube on how to apply the stuff. My favorite mistake was to apply too much graphite paint. It's not very flexible and will tend to crumble around the edges. Loose pieces of conductive graphite inside the switch is not a good thing.     -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Kaz Kylheku <kaz@kylheku.com>: Jan 15 04:31PM > Skype: JeffLiebermann AE6KS 831-336-2558   > ---     > Thanks, might give that a go.   Look, you quoted Jeff without using the correct > characters, *including his signature*, and put your reply after the signature!   Without the > characters, it looks like your posting is a plagiarism of Jeff.   When I went to reply to you, your entire reply disappeared, because your reply looks like an extension of Jeff's signature, and a proper news client removes everything after the "-- " signature mark when you reply. I had to copy and paste the above from the terminal.   Please use Usenet correctly or FOAD.

John Heath <heathjohn2@gmail.com>: Jan 14 06:52PM -0800 On Tuesday, January 12, 2016 at 9:51:45 PM UTC-5, Trevor Wilson wrote:   > --- > This email has been checked for viruses by Avast antivirus software. > https://www.avast.com/antivirus   The plate on one valve appears to have suffered somewhat !!   Here is the schematic   http://www.blueguitar.org/new/schem/peavey/c30schem.gif   You could have a leaky grid capacitor C32 or C35 .0022 uf at 400 volts if the plate appears to be over heated. They are cheap so just change them both. Also tube amps are still popular so a music sort with a repair shop will usually have a tube tester. He can match up the output tubes for gain , emission and check if gassy. If you feel uncomfortable repairing this amp a local tech in a music store can do all this for you. Do not go to the TV repair man. He is qualified but it is unlikely he will have a tube tester. You want the repair tech in a music store as he will have a tube tester and has been there done that many times and will know how to match output tubes and change coupling condensers if necessary.

Michael Black <et472@ncf.ca>: Jan 14 02:46PM -0500

jurb6006@gmail.com: Jan 14 04:12PM -0800 I don't know how you get here, but Google and aioe or whatever seem to be the only free ways to do it. Actually I probably should get a paid service but then, who gets that money ? Originally I got here via AOL but they stopped doing everything I wanted so I got rid of them.   Anyway, in Google the topics are arranged in reverse chronological order, sorted by most recent post. The date is right there, but it gives the latest date. So if it bugs you it bugs me more because I see on the right it says "4 hours ago", then I open it up and it does not skip the old posts because I have not read them through Google. Believe it or not I may have read or even be in some of these old posts. But that doesn't matter, most of my work was TVs so therefore it is all useless knowledge. Audio equipment is a different story. People are repairing and restoring old stuff every day, to the tune of mucho dinero I might add. One guy I did a job for in PA wound up with $600 into the repair. Half of that was the round trip on UPS, and they broke it ! I actually could have charged him more but I have him some money off because I put a scuff mark on the front panel. It is a Mitsubishi X-11 system with the vertical turntable. I had to fix the amp which meant retrofitting it to modern chips because the original is unobtanium, but before that I had to fix the power supply with a foil burnt off the board, which was quite worrisome at first. I had to fix a broken part in the cassette deck and put belts in that. Then when it got home, UPS somehow screwed up the TT tracking servo. I had to charge him another hundred for that but that included time and gas to meet him about halfway. We were not about to do UPS again. so about $700 for like a 25 watt per channel, magnetic cartridge (oh I replaced that also) and a pretty decent cassette deck. Although he'll never need outputs again, I used LM3886s.   At any rate, back to our regularly scheduled hijack, the people who respond to these old posts, like you said, must be finding them through a search. I mean a web search. for them to search SER, they would have to go to SER first, right ?   However, I just Googled for "Sherwood RX-5502" and no hits with "groups" on the first two pages. [   Then there is another thing, a bunch of websites archive Usenet and pretend they got a forum. Could they be finding these old posts that way ?   I mostly agree with you, but not with the preventing replies to posts over a month old. I think six months would be good. At least there's a good chance the people are still alive.

T Wood <f6ceedb9c75b52f7fcc0a55cf0cfbf5d_1028@example.com>: Jan 15 01:37AM responding to http://www.electrondepot.com/repair/sherwood-rx-5502-receiver-protection-shutdown-repair-thoug-134725-.htm , T Wood wrote:   I just wanted to say thank you. I didn't realize that was so bad!!

whit3rd <whit3rd@gmail.com>: Jan 14 12:16PM -0800 On Tuesday, January 12, 2016 at 4:50:09 PM UTC-8, avag...@gmail.com wrote:   [about ring nuts that retain a switch in a panel] > Get this...there are 7 here nutless. Collected them this afternoon. 3 are hella's for expletive deleted.     Well, you can order seven new switches, they'll come with the hardware. And you can start collecting these parts from all the discarded appliances you see.   Or you can ask an elderly coworker if he/she has a jar of these at home.   Some (not all) might be available commercially; mcmaster.com calls them 'panel nuts' but I see only inch sizes and threads.

avagadro7@gmail.com: Jan 14 04:23PM -0800 no gauge as yet....I'm planning finding an SAE fine die will butcher a metric into submission for a EUREKA !!! a panel nut.   One of the years great terminology locations...ace Dude .   As it worked in, the current project required 2 switches and there were 2 nuts.   so far right....with few threads. 3 layer plywood panel. Maybe use aluminum ...   No, the Hardware Wizard is alive and .....at work here in S. Florida with a reservoir of Liebermenn and Muzi's on hand supplementing SSA. Experts standing around bored waiting for Gyro's arrival with a puzzle.   The project is a success. Next hooking in a LED flasher relay to the Mother Ship LED installation on the roof rack side's n rear. complete with a Spanish rendition of: El Coache is backing up...and a standard truck beep beeper for exits from Mac's parking lot..   But great relief app roaching the Standard Western Interstate 3 Mile Stalled traffic Lineup at 75 mph ...just over the rise. The one past O'Neils goldmine hole ....road where the ambulance crew is onsite.     https://goo.gl/L7d8WX   the 550 mounted low as designed with 10 ga wiring from batt does the job LeMans style. One 550. The 550 pair was meant for lighting the right berm as the 550 has a tight narrow beam.   Roof mounted 550's suffer the same problem as corn grown in winter.   See al the roof mounted macho lighting setups right ? I dunno. I have't found a light ...not looking in off road tho...that flacks BEAM DESIGNED FOR ROOF MOUNTS..   Clearly the 550 was designed as a bumper level mount.   Hella fogs were tired from the roof n that was a complete loss. No go there at all.

avagadro7@gmail.com: Jan 14 04:29PM -0800 Roof mounted 550's suffer the same problem as corn grown in winter. all.   the opposite.

John Robertson <spam@flippers.com>: Jan 14 02:38PM -0800 I have a customers AWA12000 in the shop and found the first problem - a bad lithium battery - however when I have tried to archive the hard drive I find that the Baker software won't run on any of my copies. So I assume the drive has some sort of copy protection.   Baker no longer services this machine (obsolete) and will not provide ANY service information unless you are a member of their service organization. Baker was bought out by another company, but I'm calling it Baker as they built the thing.   So, the operating system is W2K, the copies boot up fine, they just won't run the Baker code. I consider this fair use as we are just trying to protect the companies investment in this tool (cost $18,000USD when new back in 2000) as the replacement units are now $40K USD! The customer does not have the backup floppies for the original code, but does have the licenced W2K CD.   I tried first with Miray's Dolly - no success at all, so I then tried my CSC HDS-4000 IDE duplicator, which made copies and claimed no errors, but these are the ones that work until I try running the analyzer code.   I figure this is some sort of soft sector copy protection, so don't want to run Spinright on the drive as that may 'fix' the problem and leave us with a big door stop.   Anyone familiar with the CSC duplicator and knows some tricks that might help?   Thanks!   John :-#)# -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

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