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oldschool@tubes.com: Feb 06 04:05PM -0600 Will Deoxit on a circuit board cause problems? In other words, is it conductive if it's touching components?   I had to spray some switches that had a very tiny hole in a plastic covering, so the Deoxit got all over the board. I removed most of it with tissue paper, but there are traces of it beneath chips and other components, which is difficult to remove. I have also used some Q-tips to get rid of as much as I can, but I cant get all of it.   Will it evaporate over time? I wont be plugging this device in for at least 24 hours.   Normally it's not this messy, but in this case there was no easy way to get it into those switches, which badly needed to be cleaned. I wish they would not seal switches like this. The old style switches with open ends were so much easier to clean.

whit3rd <whit3rd@gmail.com>: Feb 06 03:43PM -0800 > Will Deoxit on a circuit board cause problems?   Not according to the manufacturer. Various formulations have been around for decades, with no alarms raised. Relax, plug it in and go.

Jeff Liebermann <jeffl@cruzio.com>: Feb 06 04:43PM -0800 >Will Deoxit on a circuit board cause problems? In other words, is it >conductive if it's touching components?   Think about it for a moment. If a switch lube were conductive, and you sprayed it on the switch contacts, one might expect the switch lube to short out the switch. That would make it a very bad switch lube. Therefore, one might suspect that NOT shorting out the switch which Deoxit is trying to lubricate might be a formulation requirement. In other words, it better not be conductive.   Deoxit is mosly mineral oil (saturated parrafin oil) which will evaporate, but very slowly. You'll need some kind organic solvent to clean off the oil residue from the PCB. If you using Cramolin Red instead of Deoxit, there's some oleic acid in the mix as an oxide remover, which will very slowly corrode copper and must be removed from the PCB.       -- 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

oldschool@tubes.com: Feb 07 03:05AM -0600 On Tue, 06 Feb 2018 16:43:38 -0800, Jeff Liebermann <jeffl@cruzio.com> wrote:   >instead of Deoxit, there's some oleic acid in the mix as an oxide >remover, which will very slowly corrode copper and must be removed >from the PCB.   I guess I did not explain that real well. Of course it's not conductive, but what I meant is whether there could be water in it, meaning till it drys it could be conductive via the water. I know most chemicals these days cant contain solvents which are air pollution. In fact a mechanic friend told me that auto paints no longer contain laquer thinner, and some are even water based.   Knowing it's mineral oil eliminates that worry. I've never seen that Cramolin Red, but I'll be sure to never buy it. Deoxit seems to be the best anyhow, so I dont buy anything else. Years ago, I used Radio Shacks contact cleaner most of the time, which usually worked ok, but that is no longer available and Deoxit is better anyhow. It's a little on the pricey side, but I find myself using less of it than I used with the sprays I used in the past.   Thanks for the help.

gregz <zekor@comcast.net>: Feb 07 09:18AM > get it into those switches, which badly needed to be cleaned. I wish > they would not seal switches like this. The old style switches with open > ends were so much easier to clean.   Main ingredient in common Deoxit is gasoline. Well, Coleman Fuel, well Naphtha. It evaporates slower than some other solvents. The 5% oily solution remains for some time. Flammable but not conductive.   Greg

gregz <zekor@comcast.net>: Feb 07 09:31AM > days cant contain solvents which are air pollution. In fact a mechanic > friend told me that auto paints no longer contain laquer thinner, and > some are even water based.   Some areas or states might have a ban on lacquer. Not popular like once was, but common in touch up spray cans. Enamel spray with hardener is awfull to breath.     > pricey side, but I find myself using less of it than I used with the > sprays I used in the past.   > Thanks for the help.   if you want to clear boards, use a plastic safe residue free electronic spray.   Greg

"pfjw@aol.com" <pfjw@aol.com>: Feb 07 07:27AM -0800 OK - DeOxit as a contact cleaner (there are several formula) contains 95% volatile hydrocarbons and propellants if applicable, and 5% proprietary ingredients. These latter may or may not be Oleic acid, but they are reactant with various oxides of common conductive materials such as silver, copper or tin.   As long as all or part of that 5% has not reacted with one or another oxide, it will remain active. The salts produced by its reactions are, emphatically, conductive. DeOxit *MUST* be removed from whatever it goes into in order to prevent down-the-line problems. If used on a pot, the pot should be rinsed in a _lubricating_ cleaner. CRC, amongst others, makes such a material, spray or pump.   So, use DeOxit. Allow it to work while exercising the pot (or switch). Rinse & lubricate. Done.   Peter Wieck Denver, CO

oldschool@tubes.com: Feb 06 04:31PM -0600 >My sone has posted the catalog sheet I promised on   >http://www.bartlettstreet.com/electronics/PotTapers.jpg   >CP   Thanks for that info. I saved that .jpg for reference. I never knew there were that many variations. I once thought there were only two kinds of pots, linear and audio. Maybe that was true on the old tube gear, but not these days.   What catalog did that come from?   --- As an update on my Altec Lansing preamp. Altec no longer makes any of their electronics, or even has parts. The phone number is not even valid anymore. They only make speakers now.   I think I can glue some shaft onto the broken stub, so that's what I'll have to do. At least the pot is still good. In the meantime, I'll be watching ebay for an identical model which is being sold for parts. Often they sell cheaply. I plan to keep this preamp, so spare parts would be good to have.

MOP CAP <email@domain.com>: Feb 06 02:58PM -0800 I think it can from a Centralab. The only indication is CRL in a diamond in the lower corner of the full page. Glad it was of use. CP

oldschool@tubes.com: Feb 06 04:17PM -0600 On Fri, 2 Feb 2018 08:05:42 -0800 (PST), Terry Schwartz >isplayed. Any help on finding schematic etc. appreciated. Sears no longer has p >arts. Thanks!   >Perhaps a model number would help.   Why does a radial arm saw have a display? I own several of them saws and there is nothing that I could see that needs to be displayed. I set the arm to whatever angle I need, which is marked on the arm itself, and angle the blade if needed. Also labeled on the adjuster knob.   I suppose if it's a variable speed (none of mine are), that may tell you the speed, but who needs the speed to be that precise? And why a battery? Once it's plugged in, the display should turn on.   Sears obsoletes their products so quickly these days, I'll never buy any of their products again.... I dont doubt that Sears will soon close their doors permanently. So much for their supposed "lifetime warranty" on their Craftsman tools.

Jon Elson <elson@pico-systems.com>: Feb 06 10:55AM -0600 philo wrote:       > Found a part number , it's this   > https://www.bulbworks.com/light-bulbs/1406-04   > It seems to be a 5000 watt lamp 5000 W?? YIKES! OK, there should be standard ballasts for this type of lamp. Possibly bulbworks can point you to a source for the ballast. Unless you area REAL electronics guru, a failed ballast would be tricky (and dangerous) to repair.   And, be insanely cautious with this thing, a 5 KW UV light source will take your skin off with just a few seconds exposure. I got a severe sunburn trying to set up the optics with a 200 W short arc lamp, and I was barely exposed for a minute before deciding I needed to pop in a grain of wheat bulb for initial setup.   Jon

philo <philo@privacy.net>: Feb 06 11:01AM -0600 On 02/06/2018 10:55 AM, Jon Elson wrote: > exposed for a minute before deciding I needed to pop in a grain of wheat > bulb for initial setup.   > Jon   At this point it would be impossible for me to put the thing back together again in it's original configuration.

Fox's Mercantile <jdangus@att.net>: Feb 05 08:54PM -0600 On 2/5/18 6:21 PM, tom wrote:   > Be very careful with that lamp. They are under very high pressure and can > explode if dropped or scratched.   Note also numerous warnings about "DO NOT TOUCH" Finger oils on the bulb can cause catastrophic failures.     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

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