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Chris Jones <lugnut808@spam.yahoo.com>: May 23 10:16PM +1000 On 23/05/2015 00:53, Jeff Liebermann wrote: > the excess solder from the tiny SMD parts.   > Reminder: Welding gloves, face shield, safety glasses, and > ventilation.   I found this page really interesting about parts recycling:   https://techtravels.wordpress.com/shenzhen-phone-recycling-2/   Beginning: https://techtravels.wordpress.com/shenzhen-phone-recycling-1/ (Start at the beginning - I just wanted to make sure you don't miss the "more" link...)

Jeff Liebermann <jeffl@cruzio.com>: May 23 08:50AM -0700 On Sat, 23 May 2015 22:16:57 +1000, Chris Jones >https://techtravels.wordpress.com/shenzhen-phone-recycling-1/ >(Start at the beginning - I just wanted to make sure you don't miss the >"more" link...)   So, now you know where I buy my phone repair parts. My dead phone collection isn't as impressive. Photos later.   Locally, there's actually a demand for old phones. I was getting phones for about $5/ea from the local recycler, until someone offered them more money. Since I wasn't making much money fixing phones, I declined to start a bidding war.   Note the heat guns in the photos. They look brand new and recently installed with tape. My guess(tm) is that these burn out rather often. They're not made for continuous operation. It's NOT a cheap heat gun and includes an LCD display for monitoring temperature: <http://www.amazon.com/Steinel-2310-Industrial-Display-without/dp/B000CORPVG> at $300 list price.   -- 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

"Michael A. Terrell" <mike.terrell@earthlink.net>: May 22 11:00PM -0400 Gareth Magennis wrote:   > Are these things really just plug and play?   > Are these cheapo things often DOA or maladjusted/untested etc?   > Have I missed anything else?     Is the soldering iron's tip properly grounded? Our limit at Microdyne was three ohms form the tip, to the bench's ground connection to the electrical system.

"Mark Zacharias" <mark_zacharias@labolgcbs.net>: May 23 07:24AM -0500 "Gareth Magennis" <sound.service@btconnect.com> wrote in message news:nSI7x.510295$qW.251544@fx20.am4...   > Gareth.   I have long suspected the laser power adjustments on the cheapies are shipped unadjusted - perhaps merely centered.   Mark Z.

M Philbrook <jamie_ka1lpa@charter.net>: May 22 07:29PM -0400 In article <mjm9t5$2kd2$1@usenet.ziemba.us>, paul+usenet@w6yx.stanford.edu says...   > I have schematics, but I am stumped as to how to proceed further. Has > anyone encountered this kind of problem and found a fix?   > Many thanks!   time for a recapping.... You have one that is shorting, it does not need to be swollen as you say, most likely a small package cap with a lot of F for its size.   Jamie

"Mark Zacharias" <mark_zacharias@labolgcbs.net>: May 23 06:23AM -0500 "G. Paul Ziemba" <paul+usenet@w6yx.stanford.edu> wrote in message news:mjm9t5$2kd2$1@usenet.ziemba.us... > G. Paul Ziemba > FreeBSD unix: > 9:06PM up 48 days, 21:38, 11 users, load averages: 0.70, 0.64, 0.65     Wow - I was typing a big long reply and my mail program crashed, lost it all.   OK.   1. It would be helpful to know if the pop is on one channel or all. All channels would point to a power supply problem, such as perhaps bad solder at a fixed voltage regulator. Probably a good idea to resolder all your TO-220 style voltage regulators for good measure.   2. The base voltages should be around 1.1 volts or so. Although the service manual incorrectly drew the ouputs as bipolar, they are Darlingtons, the voltages shown in the schematic are correct. I have serviced Sony receivers of this general type for over 20 years, and this has virtually always been the case. If you really read 0.6 volts on the bases, you may need a new multimeter. The MUTE function of the driver IC's would have resulted in 0 volts at the base, and it's not a bias problem, so there you go.   3. The uPC 2581 driver ic's do run quite hot and dry out nearby caps. The IC's should be resoldered and any suspect caps replaced. The STK350-230 (IC501) is a VERY common troublemaker - although not often intermittent, usually just bad (at least by the time I see them).   Mark Z.

N_Cook <diverse@tcp.co.uk>: May 23 10:45AM +0100 > in both NIR and NUV. Is it possible that NUV might go through the > wallpaper? > Eric   A assume it was near UV, 20 LED cluster only labelled UV , numerous materials flourescing under it. I returned to the test wallpaper patch and tried straight on and oblique with various visibly opaque or going on opaque "filters" over the webcam lens , passing the UV image, mylar, polyester , black polythene, CD in overprinted-free area of label, floppy disc material blocked the uv illuminated image. Could see not the slightest hint of any letters under the paper wiht any of them, or absent filter, but could see the wallpaper printed design in each case, but nothing in the background room light illumination.

"Michael A. Terrell" <mike.terrell@earthlink.net>: May 22 08:08PM -0400 > I can't seem to get a print for that unit but from what you wrote I owuld bet you have a 12 volt regulator out.   > If it has mechanical switches, you say the "lock" in, then it does not use that unobtainium IC. It might use some 4066 type CMOS switches but those are easy to get. But the fact there are lights not lighting means likely a supply is missing.   https://www.samswebsite.com/en/photofact/details/index/id/50794

jurb6006@gmail.com: May 22 05:35PM -0700 Paying for the manual would be alright if I was working on it here. But for someone on the web at random, no. Can't do that.   Thanks anyway. Maybe the OP wants it though.   Interesting that is an OEM manual they say. Usually they generated their own. Are they like a licensed reseller or something now ? they used to reverse engineer almost everything, but I know that has gotten more difficult by orders of magnitude.

"Michael A. Terrell" <mike.terrell@earthlink.net>: May 22 10:26PM -0400 > Paying for the manual would be alright if I was working on it here. But for someone on the web at random, no. Can't do that.   > Thanks anyway. Maybe the OP wants it though.   > Interesting that is an OEM manual they say. Usually they generated their own. Are they like a licensed reseller or something now ? they used to reverse engineer almost everything, but I know that has gotten more difficult by orders of magnitude.     They ended up with the huge collection of OEM manuals the NRI had, when that school was shut down by McGraw-Hill. I once asked about information on a 1938 Philco tombstone radio from NRI, and they mailed me an original service manual for free, since I had taken a course at one time.   Sams only reverse engineered items that sold in excess of 20 thousand units, but they collected OEM data on everything they could get their hands on. They also wrote manuals for some company's products that didn't meet the 20K unit minimum. Those were only available from the OEMs.

Phil Allison <pallison49@gmail.com>: May 22 11:20PM -0700 Tim R wrote:   > > input, feeding signal to the volume/tone controls.   > > Leif   > So is there any harm in just running it that way and using it?     ** Nope.       .... Phil

energyhealingarts@gmail.com: May 22 05:26PM -0700 Hi, I want to switch this bug zapper over to led or cfl light. I figured the hi voltage transformer primary was 120v but the primary is connected to the florescent bulbs. I guess so you have to buy their replacements. Does anyone know what kinda power I could connect to the high voltage transformer if I replace the florescent bulbs. I imagine this circuit board needs to see the voltage from the ballast or it won't work either so it probably needs a total redesign. These bulbs needed replacing and I thought it would cool to replace them with leds. Thanks in advance Rob

energyhealingarts@gmail.com: May 22 05:33PM -0700 > Hi, I want to switch this bug zapper over to led or cfl light. I figured the hi voltage transformer primary was 120v but the primary is connected to the florescent bulbs. I guess so you have to buy their replacements. Does anyone know what kinda power I could connect to the high voltage transformer if I replace the florescent bulbs. I imagine this circuit board needs to see the voltage from the ballast or it won't work either so it probably needs a total redesign. > These bulbs needed replacing and I thought it would cool to replace them with leds. > Thanks in advance Rob   Sorry, I had meant to attach a photo and can't see how to do that, that's probably not an option on this list.

"Rheilly Phoull" <rheilly@bigslong.com>: May 23 10:27AM +0800 wrote in message news:64a82aae-dbe3-4e8a-b94d-3d41c666ead3@googlegroups.com...   > These bulbs needed replacing and I thought it would cool to replace them > with leds. > Thanks in advance Rob   Sorry, I had meant to attach a photo and can't see how to do that, that's probably not an option on this list.   Google "Dropbox" for a free photo sharing site.

Phil Allison <pallison49@gmail.com>: May 22 08:35PM -0700 Rob wrote:   > Hi, I want to switch this bug zapper over to led or cfl light.   ** Most bug zappers use a special fluoro tube that emits lots of UV light to attract the bugs. LEDs emit none and CFLs very little.   Your other questions are to vague to answer.       ... Phil

Rob <energyhealingarts@gmail.com>: May 22 10:55PM -0700 Here are links to the photos.   https://www.dropbox.com/s/tbgti7314gyxk5p/20150523_003930.jpg?dl=0     https://www.dropbox.com/s/0zyd7gutbyi3229/20150522_190329.jpg?dl=0

"Gareth Magennis" <sound.service@btconnect.com>: May 22 05:59PM +0100 wrote in message news:4ab48115-270e-465d-9a15-be447aa2d514@googlegroups.com...   The discussion of the device in series with the Cannon XLR jogged my memories of the Polyswitch, a protective device whose resistance jumps up when sufficiently heated (via current), but goes back down when it has cooled off.   http://www.te.com/usa-en/products/circuit-protection/overcurrent-devices/polyswitch-resettable-devices.html   We ended up not using them, but now I am curious if they show up in damaged equipment.             I know I've bought at least one, so the answer must be yes.     Gareth.

Mike Tomlinson <mike@jasper.org.uk>: May 22 07:24PM +0100 En el artículo <4ab48115-270e-465d-9a15-be447aa2d514@googlegroups.com>, >my memories of the Polyswitch, a protective device whose resistance >jumps up when sufficiently heated (via current), but goes back down >when it has cooled off.   I thought they were called polyfuses.   --

N_Cook <diverse@tcp.co.uk>: May 22 08:01PM +0100 > http://www.te.com/usa-en/products/circuit-protection/overcurrent-devices/polyswitch-resettable-devices.html   > We ended up not using them, but now I am curious if they show up in > damaged equipment.   I recently had a pair of polyswitches, same size and markings, in the same kit, with both cold one was 0.5 ohm or so greater ohmage than the other. Not that that was the problem.

whit3rd <whit3rd@gmail.com>: May 22 12:29PM -0700 > http://www.te.com/usa-en/products/circuit-protection/overcurrent-devices/polyswitch-resettable-devices.html   > We ended up not using them, but now I am curious if they show up in > damaged equipment.   Yes, there were quite a few damaged polyswitches in the 1990's vintage SCSI (computer bus) systems; these were used in powering the required resistor arrays (called terminators), and were a big improvement over the previous generation (which used fuses).   The problem, is that you couldn't power the bus without taking precautions because other bus-resident boxes could have different +5V levels, or could be powered off, or have unstable voltages, and were ALSO connected to that same wires on the bus.   The issue I saw was usually brittle fracture, and mainly on the surface-mount types. Before polyswitches, there were lots of fuses (one inside each CD or hard drive mechanism) and when a fuse went out, the whole bus could lose its logic power (or not, depending on which particular devices were plugged in). A surge could pop two fuses, and leave the third device (like, a scanner) as the only bus power source. When you unplugged that scanner, the hard drive became unusable.

Phil Allison <pallison49@gmail.com>: May 22 09:14PM -0700 > http://www.te.com/usa-en/products/circuit-protection/overcurrent-devices/polyswitch-resettable-devices.html   > We ended up not using them, but now I am curious if they show up in > damaged equipment.   ** Polyswitches are damaged ( blown apart) by overvoltage when in the high resistance mode. The maximum ratings vary from 16V to 250V AC for different devices.   Polyswitches are in fact *temperate operated* so will switch at lower current when the ambient temp is higher than rated, usually 20C.   Another issue is that returning to the original low resistance value after cooling can take some time, days even - meanwhile the trip current will be lower than before.   Good practice is to make the trip current occur at double or more the normal running current and also allow for the effect of a hot environment.       ... Phil

Phil Allison <pallison49@gmail.com>: May 22 09:24PM -0700 Mike Tomlinson wrote:     > I thought they were called polyfuses.   ** Yeah, that is one of the names they go by, but is actually a trade name registered to Littelfuse.     .... Phil

mike <ham789@netzero.net>: May 22 07:16PM -0700 On 5/22/2015 8:12 AM, Jeff Liebermann wrote:   >> parts with that.   > Ozone depleting Freon has not been used in freeze spray for maybe 20 > years. Tetrafluoroethane is what's used these daze.   I've had this can of freeze spray for 30 years or more. ;-)

Peter Easthope <petereasthope@gmail.com>: May 22 11:16AM -0700 On Thursday, May 21, 2015 at 12:23:13 AM UTC-7, N_Cook wrote: > you should be able to sense where the catch points are. Then out with > the big blade. After all the monitor is broken anyway, so nothing to > loose if you should crack part of the case.   Thanks. Will have another go at it after June 1, ... Peter E.

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