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Saperstein <none@nowhere.com>: Nov 25 09:34AM -0500 I have been using a spare heating pad to keep an outdoor feral cat warm. Although I have it on a timer now so it doesn't heat continually, I'd rather go with something weight activated so that, once the cat steps onto it, it comes on and is otherwise off. Could I fashion something myself that would do the job? If not, or as an alternative, what are some ready made options that aren't costly? Thankyou.

KenW <ken1943@invalid.net>: Nov 25 08:50AM -0700 On Thu, 25 Nov 2021 09:34:37 -0500, Saperstein <none@nowhere.com> wrote:   >onto it, it comes on and is otherwise off. Could I fashion something >myself that would do the job? If not, or as an alternative, what are >some ready made options that aren't costly? Thankyou.   Google >heat activated heating pad< does get hits     KenW

KenW <ken1943@invalid.net>: Nov 25 08:52AM -0700 On Thu, 25 Nov 2021 09:34:37 -0500, Saperstein <none@nowhere.com> wrote:   >onto it, it comes on and is otherwise off. Could I fashion something >myself that would do the job? If not, or as an alternative, what are >some ready made options that aren't costly? Thankyou.   Just check if waterproof     KenW

John Robertson <spam@flippers.com>: Nov 24 02:26PM -0800 My son-in-law asked me to look at his JV80 Roland keyboard as it didn't seem to work properly.   Found the operators and service manuals on line and discovered the keyboard wouldn't go into self test. Took back off and started checking the switches - found that ALL 54 push-button PC mount switches had failed or were marginal at best.   Replaced all the switches (gotta love single sided phenolic PCBs...) and now it works a treat.   So if you have any musician friends with wonky keyboards the solution is often simple...   John :-#)# --

Tim R <timothy42bach@gmail.com>: Nov 25 06:28AM -0800 On Wednesday, November 24, 2021 at 5:26:29 PM UTC-5, John Robertson wrote: > often simple...   > John :-#)# > --   Just curious. That's an older 61 key synth, per google. (I'd not heard of a 54 key keyboard so I looked it up.) So why are there only 54 switches for 61 keys?

Jeff Liebermann <jeffl@cruzio.com>: Nov 24 10:08AM -0800 >I have a need to use some nichrome wire for an outdoor project where it >will be partially exposed to the elements (mainly humidity extremes but >also might get wet at times). Is it corrosion proof? Thank you.   My house has a nichrome wire bathroom wall heater. No corrosion in about 50 years in a rather wet and humid bathroom environment. However, I'm not sure what nichrome will do in a marine (salt) environment. My guess(tm) is that it's ok but it might help to check if you're using it in a marine environment.         -- Jeff Liebermann jeffl@cruzio.com PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558

"Peter W." <peterwieck33@gmail.com>: Nov 24 10:58AM -0800 > ** Can't you coat is in a lacquer to keep water off ? > Will it get hot?   Nichrome. Lacquer. Water. Think about it. "Water damages lacquer by turning it milky and hazy. Finishers call this milkiness "blushing" when it occurs while the finish is being applied. Water also can be responsible for the white rings produced by hot or wet glasses and pots left standing on a lacquered tabletop."   Nichrome is chosen, typically, for its heating quality under power. Lacquer is generally not a heat-resistant product. Lacquer is also not a water-resistant product as normally formulated.   Peter Wieck Melrose Park, PA

Phil Allison <pallison49@gmail.com>: Nov 24 12:03PM -0800 Peter W. wrote: ------------------------ > > ** Can't you coat is in a lacquer to keep water off ? > > Will it get hot?   > Nichrome. Lacquer. Water. Think about it.   ** Acrylic lacquer is waterproof.   > Nichrome is chosen, typically, for its heating quality under power.   ** In electronics it is used for its zero tempco of resistance.   FFS I posted question, not statements.   YOU should do the same - asshole.

"Peter W." <peterwieck33@gmail.com>: Nov 25 04:47AM -0800 "Acrylic" lacquer is not lacquer.   The correct formula Nichrome to the use needs no protection. It would make sense to choose the correct formula rather than to go to heroic measures to protect the wrong one.   Heating would obviate the applied 'protection' in any case.   Eschew needless complexity - William of Occam   Peter Wieck Melrose Park, PA

Phil Allison <pallison49@gmail.com>: Nov 25 04:54AM -0800 Peter Wanker is not Human wrote: ====================   > "Acrylic" lacquer is not lacquer.   ** ROTFLMAFAO !!!!!!!!!!!!!!!!   > The correct formula Nichrome to the use needs no protection.   ** What use ?????   > Heating would obviate the applied 'protection' in any case.   ** Bollocks .   Wot a fucking nut case IDIOT       ... Phil

Michael Terrell <terrell.michael.a@gmail.com>: Nov 24 09:48AM -0800 > I'd be inclined to just do an easy work around. Two 12V (7812/7912) ICs can do all of that with almost no rewiring, particularly if you don't need the supplies to be adjustable. The two ICs will even mount on the heatsinks in place of those two regulator transistors.   Two issues. Two separate regulators don't track, and the 1A limit may be too low.   Non tracking regulation can case excessive drift and affect gain problems in the Vertical amplifiers.   A good lab grade bench supply could be used for testing, but I wouldn't use one rated at under 3A   I've done a lot of work on complex Dc circuits where a small difference in the supply rails from what was specified will cause it to fail. The required bench supply was to the milivolt, to achieve the maximum allowed1.5 milivolt at the output of the 14 op amp gain control subsystem. Your test equipment has to be better than what you work on.

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