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mhooker32@gmail.com: Jul 14 04:03PM -0700 On Thursday, July 13, 2017 at 4:03:55 PM UTC-4, Ian Field wrote:   > Last time I ordered diodes - all the PIV grades were the same price, I just > ordered the highest grade in a larger quantity.   > I have absolutely no idea how they grade production and marketing.   well, i got the new chassis and its working correctly. turns out my chassis i recapped and went all sorts of nuts on is most likely good. it was the control board with size, horz, vertical, contrast and the other adjustments. it plugs in via a ribbon cable. if i use my old control board with the new chassis, i get the same half image. i never thought control board, as i got the half image with the board connected and unconnected, and mvoing the pots made no difference. i have both boards and will go over the pots, resistors, 1 diode and 1 cap. see whats bad on the affected board, maybe the cable itself. its soldered, not crimped. i cant really test my old chassis, i had to use my old neck board, it was for a 13, not 19 inch monitor. not going to swap neck boards back and forth, im just glad its working. i will let all know if i find the control board issue

John Robertson <spam@flippers.com>: Jul 14 04:19PM -0700 >> ordered the highest grade in a larger quantity.   >> I have absolutely no idea how they grade production and marketing.   > well, i got the new chassis and its working correctly. turns out my chassis i recapped and went all sorts of nuts on is most likely good. it was the control board with size, horz, vertical, contrast and the other adjustments. it plugs in via a ribbon cable. if i use my old control board with the new chassis, i get the same half image. i never thought control board, as i got the half image with the board connected and unconnected, and mvoing the pots made no difference. i have both boards and will go over the pots, resistors, 1 diode and 1 cap. see whats bad on the affected board, maybe the cable itself. its soldered, not crimped. i cant really test my old chassis, i had to use my old neck board, it was for a 13, not 19 inch monitor. not going to swap neck boards back and forth, im just glad its working. i will let all know if i find the control board issue   Thanks for the update! I had forgotten about the sub-board controller too, and we have run into that with other monitors.   I suspect now that one of the vertical potentiometers is damaged.....   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

mhooker32@gmail.com: Jul 15 09:25AM -0700 On Friday, July 14, 2017 at 7:19:32 PM UTC-4, John Robertson wrote: > (604)872-5757 (Pinballs, Jukes, Video Games) > www.flippers.com > "Old pinballers never die, they just flip out."   the vert pot is open. schematic shows a 500ohm B pot. what is the b for. two of the pots have the b suffix. google had conflicting info that its a log pot, but testing the good one with a dvm, it looks linear( i need a battery for my analog meter) . thanks

ABLE1 <someone@nowhere.net>: Jul 14 08:45PM -0400 Hello all,   I have a sound amplifier board with what looks like some 25v 220mfd radial capacitors that appear to have leaked some of the electrolyte on to the board. The board is easily 20+ years old.   One of the IC chips that is in the area appears to have some corrosion on the pins.   If someone would be so kind to answer my questions they are as follows:   Is the electrolyte some kind of acid base??   Will washing the board with contact cleaner properly clean and or neutralize the effects??   I plan on replacing the bad capacitors but want to be sure I am not missing something. I don't want to replace the chip unless it is damaged in some way.   Thanks for any hints or tip on this matter.   Have a good day.   Les

"tom" <tmiller11147@verizon.net>: Jul 14 08:51PM -0400 "ABLE1" <someone@nowhere.net> wrote in message news:NAdaB.89557$5A2.42585@fx28.iad...   > Thanks for any hints or tip on this matter.   > Have a good day.   > Les   Remove the capacitors and wash the board with detergent and warm water. Use a brush to scrub where there is corrosion.   Dry in oven at 50-60 °C for several hours.

Phil Allison <pallison49@gmail.com>: Jul 14 08:31PM -0700 ABLE1 wrote:   ---------------- > on the pins.   > If someone would be so kind to answer my questions they are as follows:   > Is the electrolyte some kind of acid base??   ** It's usually ethylene glycol plus boric acid and loves to attack copper.     > Will washing the board with contact cleaner properly clean > and or neutralize the effects??   ** Contact cleaner is undefined, can be damn near anything.   I use a "Circuit Boaord Cleaner" that has a combination of hydrocarbon solvents and dries quickly.     > I plan on replacing the bad capacitors but want to be sure I am > not missing something. I don't want to replace the chip unless > it is damaged in some way.     ** Clean it up best you can and watch out if electrolyte has gone underneath.   I have found a small fibreglass brush useful. http://au.element14.com/duratool/d02266/pen-pcb-cleaning-fibreglass-4mm/dp/2102028   Really bad cases may need immersion in hot, detergent water to come good.       .... Phil

tabbypurr@gmail.com: Jul 15 04:16AM -0700 On Saturday, 15 July 2017 01:51:00 UTC+1, tom wrote:   > Remove the capacitors and wash the board with detergent and warm water. Use > a brush to scrub where there is corrosion.   > Dry in oven at 50-60 °C for several hours.   Detergents also tend to be corrosive long term so clean it off well.     NT

ABLE1 <someone@nowhere.net>: Jul 15 08:09AM -0400 On 7/14/2017 11:31 PM, Phil Allison wrote:   > Really bad cases may need immersion in hot, detergent water to come good.   > .... Phil   Tom, NT, Phil, Thanks for all the input.   I get the idea on cleaning. BTW as for "Contact Cleaner" I was referring to this one.   https://www.zoro.com/crc-electronic-component-cleaner-13-oz-02200/i/G8578595/ Or similar, but may not be the most desired.   Phil, as for the term "Circuit Board Cleaner" is there a specific brand that you use??   Presently searching for replacement caps. Once I acquire them I will dive into this project.   Another question: Concerning the chip that has been effected. Can or could the electrolyte leach into the chips at the pins and cause problems with the chip in some way?? Or is the chip considered hermetically sealed is some fashion??   Thanks again!! Do appreciate the insight.   Les

tabbypurr@gmail.com: Jul 15 05:14AM -0700 On Saturday, 15 July 2017 13:09:57 UTC+1, ABLE1 wrote:   > hermetically sealed is some fashion??   > Thanks again!! Do appreciate the insight.   > Les   if they weren't sealed they wouldn't last long     NT

ABLE1 <someone@nowhere.net>: Jul 15 12:24PM -0400 >> Les   > if they weren't sealed they wouldn't last long   > NT   Thanks NT,   I got it. Was just wondering if the "seal" would be effected by the leaking electrolyte is some way.   As a general question on these capacitors that leaked. Given the age (20+ years) would it be that they would have been effected by a power surge or just old age.   There are other radial caps on the board of the same size and value that do not show any leakage.   I am asking in respect that given the condition should I just replace them all or only those that have leaked??   For me this is more of a fun experiment of sorts. I have been working with various electronics for 40++ years or so. Running my own business for the past 29 years.   I have in the past but rarely have I gotten down to board level. As you can guess, if a component or board failed it was trash it and install a new. For critical devices it is not worth the time and liability to play around with board components.   This project is quite different. I have already replaced the sound board with another and the repair project is completed.   Just waiting to be paid. :-)   I just want to see if my observation as to the condition of the caps was the real problem and can I fix it by doing a little board de-soldering, etc. Already on Digi-Key trying to source replacements.   Again, thanks for the hints. Have a good rest of your weekend.   Les

micky <NONONOmisc07@bigfoot.com>: Jul 15 03:48AM -0400 In sci.electronics.repair, on Wed, 12 Jul 2017 21:12:05 -0500, "."   >> New owner gets a working stereo and doesn't think you're an a$$ for >> trying to sell one that doesn't work (added value when you don't have a >> list of "this doesn't work" items)   The car needs a lot of work and I'm only hoping to get 1000 dollars for it, and I'm going to tell the prospective buyer that the CD doesn't work.   But it runs very well, very quiet, and very smooth, and only has 95,000 miles. However the rear window and top need replacing for $2000 iirc and, in the by far the biggest repair failure of my life, I took apart the passender door, the console, and the lower dashboard/glove complartment, and don't feel like putting them back together again, though I will be glad to help the buyer.   >> You get your CDs back undamaged, and it doesn't matter if the unit is >> destroyed in the process.   >http://www.fixya.com/cars/t213159-toyota_dashboard_cd_player_eject   Wow, this is right on the money. The question is about the same car and the same radio I have, and there are lots of answers. Just what I hoped for. Thanks. And there is a link to another page. Unfortunately none worked. Because it's a changer, there is no pin hole to release the tray (there is no tray, as such) and even though I can take off the cover and push the top cd towards the opening, something big is in the way. And I haven't disconnecte the battery or taken out the fuses, but I've taken out the radio 3 times now.   The big problem seems to be that there seem to be no power to the CD. I tried pushing the button harder and from a different angle, tried pushing combinations of buttons, looked again for a CD fuse. I'm quite surprised that the electronics would fail as well as t he mechanism.   I can unscrew a little of the frame, as Paul in Houston suggests, but the rest of "taking it apart" will have to be done with a saw. I'm not kidding. It's no loss because the CD player is kaput and I don't think I will hurt the radio or cassette (which work well). These things are usually modular, and I dout think there are any radio parts in the metal box which is the CD.   Thanks everyone.

ralph <ralph@alt.home.repair>: Jul 15 09:44AM -0400 On 07/12/2017 04:36 PM, micky wrote: > How to remove CD's from broken auto CD changer?   > I have a 2000 Toyota Solara with a factory AM-FM-CD changer, all in the > dash, not the trunk.     Good Lord! What kind of Luddite is still using a CD in a car?   Install a unit that will read a USB thumb drive or MP3 player.

micky <NONONOmisc07@bigfoot.com>: Jul 14 07:27PM -0400 In sci.electronics.repair, on Sat, 01 Jul 2017 00:42:23 -0400,   >But I am asking about this because I am a little concerned that the >dimmer could be hard on the motor, since these dimmers are made for >lighting, not motors......   I've used various light dimmers to control various table fans, built between 1935 and ~1990. The first hour or two, several times I check each fan to see if it's overheating. None have, but one out of 5 or 8 didn't work at all on any setting of the dimmer. The other 4 or 7 worked fine. I never slow the fan to stopping speed or even close. I like my fans to be so slow I don't hear them, but they still blow quite a bit of air at that speed. . I've done this for 30 years, and right now there's a 3-speed 12" fan blowing on me. Even the low speed was too high, theough iirc I have this on speed 2, and dimmed from there. Been using it all summer for at least 3 years.

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