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Ralph Mowery <rmowery28146@earthlink.net>: Nov 22 04:11PM -0500 In article <qr9e6p$7f6$1@dont-email.me>, curd@notformail.com says...   > Question is, what is the correct name for this 'mystery component' and > what should it read resistance-wise when cold?   It might be a simple fuse. See if the resistance is zero/near zero when warm and cold. Can not tell from the photo, but looks tohave a 7A over the 120 volt.

Andy Burns <usenet@andyburns.uk>: Nov 22 08:17PM Cursitor Doom wrote:   > https://tinyurl.com/t7s6og8   > Question is, what is the correct name for this 'mystery component'   PTC thermistor? thermal fuse?   <http://www.aolittel.com/sale-10973142-aupo-p3-f-pico-subminiature-pellet-ceramic-thermal-fuse-tf-cutoff-125c-250v-2a-axial-leaded-for-air-.html>

Cursitor Doom <curd@notformail.com>: Nov 22 07:50PM Gentlemen,   I refer to you this photo of the internals of a typical modern cheap and nasty blanket controller. All the components it uses are shown on this board: just 5 diodes, 3 resistors and some 'mystery component' whose function is presumably to sense overheating from the two resistors it's between and cut-back the mains voltage to the blanket itself if needed.   https://tinyurl.com/t7s6og8     Question is, what is the correct name for this 'mystery component' and what should it read resistance-wise when cold?   Thanks!       -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition.

Cursitor Doom <curd@notformail.com>: Nov 22 07:53PM > Question is, what is the correct name for this 'mystery component' and > what should it read resistance-wise when cold?   ... and (I forgot first time around)... why have they put a couple of turns in each of the leads?       -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition.

Cursitor Doom <curd@notformail.com>: Nov 22 09:53PM On Fri, 22 Nov 2019 20:17:25 +0000, Andy Burns wrote:   > PTC thermistor? > thermal fuse?   > <http://www.aolittel.com/sale-10973142-aupo-p3-f-pico-subminiature- pellet-ceramic-thermal-fuse-tf-cutoff-125c-250v-2a-axial-leaded-for- air-.html>   Bingo, Andy! Good call.       -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition.

Cursitor Doom <curd@notformail.com>: Nov 22 09:54PM On Fri, 22 Nov 2019 16:11:31 -0500, Ralph Mowery wrote:   > It might be a simple fuse. See if the resistance is zero/near zero when > warm and cold. Can not tell from the photo, but looks tohave a 7A over > the 120 volt.   It's actually 2A in this case. Andy's suggestion was correct. But like you say, the resistance should be pretty low whereas it's actually infinite, so looks like it's blown.       -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition.

marty <m@m.org>: Nov 23 06:08PM +1100 On 23/11/19 5:34 pm, whit3rd wrote:   > The diodes presumably send current to heating element A on > positive half-cycles, and heating element B on negative half-cycles > (so as to retain some function if one element fails open-circuit).   It's cactus, throw the thing out.

Fox's Mercantile <jdangus@att.net>: Nov 21 03:49PM -0600 >>> NT   >> Like I said, you're a hack.   > like I said you're childish.   That's your opinion. My opinion is that you're hack.     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Fox's Mercantile <jdangus@att.net>: Nov 22 04:22AM -0600 On 11/22/19 3:22 AM, Cursitor Doom wrote: > On Thu, 21 Nov 2019 15:49:38 -0600, Fox's Mercantile wrote:   >> My opinion is that you're hack.   > My opinion is you're Phil Alison and ICTFP.   Oh look, the hacks are circling the wagons.       -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Jeff Liebermann <jeffl@cruzio.com>: Nov 22 07:54AM -0800 On Sun, 10 Nov 2019 13:37:34 -0000 (UTC), Cursitor Doom >failed, just the unmistakable smell that *something* has. The device >still powers up fine and the screen traces are normal, so wtf else goes >*bang* and smells toxic?   You seem to be floundering:   1. Are you sure that it was the HP VNA that blew a capacitor or something? When you removed the case, was it lit up?   2. Toxic smells tend to be cause by vaporized electrolye. That leaves a messy stain which should have been present. If you can't see the damage, perhaps playing bloodhound and smelling for the damage might help. Find a vinyl hose, cram it into your nose, and sniff around the VNA and the shop for the strongest smell. Unless you use an air freshener (nasal desensitize), you should be able to find the source many days after it went bang.   3. When you tested the electrolytics, did you use both an ESR meter and a capacitance meter? If the ESR meter doesn't show a problem, the capacitance meter might.   4. Do you have a UV LED flashlight? When tracking down bulging electrolytic problems on computah motherboards, I sometimes (not always) can seen the electrolyte residue using a UV flashlight.   5. Did you have the AC power switch set for 230VAC or 117VAC?   6. Check if the small is coming from a power strip. The MOV's sometimes go bang.   Argh, gotta run... -- 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

Cursitor Doom <curd@notformail.com>: Nov 22 09:22AM On Thu, 21 Nov 2019 15:49:38 -0600, Fox's Mercantile wrote:   > My opinion is that you're hack.   My opinion is you're Phil Alison and ICTFP.       -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition.

Jeff Liebermann <jeffl@cruzio.com>: Nov 23 08:45AM -0800 On Sat, 23 Nov 2019 01:37:35 -0000 (UTC), Cursitor Doom >That cap has now been replaced and the device appears to be working fine >again, although after 10 years of storage there's no doubt some re- >aligning and whatnot to be done.   62 articles and growing. I got lazy and just skimmed the articles posted by those who had a history of successful troubleshooting. I didn't see anything that looked like success, so I posted my suggestions on the assumption that the obvious culprits and usual suspects had been eliminated. Anyway, congrats on fixing the problem.       -- 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

etpm@whidbey.com: Nov 21 05:35PM -0800 I'm pretty bsure this is a real long shot. I have looked online but have not yet found something that will help. So I ask here. The EPROM reader/programmer arrived yesterday and it works fine. The UV EPROM eraser should be here in a day or two. Amazon apologized for the delay. So I can copy the EPROMs just fine but I would really like the ladder programs so that I can make some changes to the machine. I understand that the decompiled ladder will noit have mnemonics but maybe I can decipher it anyway. The control in question is a FANUC 3T. Thanks, Eric

Fox's Mercantile <jdangus@att.net>: Nov 21 08:33PM -0600 On 11/21/19 8:09 PM, Clifford Heath wrote: >> Eric   > How in heck do yu expect help with a decompiler when you haven't told > anyone what type of CPU it is?   Please try to pay attention. "The control in question is a FANUC 3T."       -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

etpm@whidbey.com: Nov 22 09:07AM -0800 On Thu, 21 Nov 2019 23:59:31 -0800 (PST), whit3rd <whit3rd@gmail.com> wrote:     >> > "The control in question is a FANUC 3T."   >A manual found online says the 3T master board uses an 8086, so it'll decompile >as an 8088 would (different bus, but same opcodes). Thanks You. Now maybe I can find something to work. This stuff is way out of my experience but with some guidance I'm hoping to be able to decipher the ladder. Eric

etpm@whidbey.com: Nov 22 09:06AM -0800 On Fri, 22 Nov 2019 13:09:58 +1100, Clifford Heath >> Eric   >How in heck do yu expect help with a decompiler when you haven't told >anyone what type of CPU it is? Well, that's why I'm asking for help. I know hardly anything about this stuff. Eric

Clifford Heath <no.spam@please.net>: Nov 22 01:09PM +1100 > The control in question is a FANUC 3T. > Thanks, > Eric   How in heck do yu expect help with a decompiler when you haven't told anyone what type of CPU it is?

Bill Martin <wwm@wwmartin.net>: Nov 21 06:33PM -0800 On 11/21/19 6:09 PM, Clifford Heath wrote: >> Eric   > How in heck do yu expect help with a decompiler when you haven't told > anyone what type of CPU it is? It's even harder...ladder logic isn't a "cpu machine language" as such, it's an interpreter running in some native cpu machine language...so there would be a whole other layer of translation involved in order to produce anything a human might be able to comprehend. Unless your computer is made from relays...but why bother.

Clifford Heath <no.spam@please.net>: Nov 22 03:22PM +1100 On 22/11/19 1:33 pm, Fox's Mercantile wrote: >> anyone what type of CPU it is?   > Please try to pay attention. > "The control in question is a FANUC 3T."   That's the packaged controller. It contains a CPU. The CPU interprets some ladder codes.   It's highly unlikely that the information required to decode the EPROM has ever been published. This sort of thing is usually trade secret.   If the CPU is known, and the interpreter ROM is read, there's some possibility of using a decompiler.

John Robertson <spam@flippers.com>: Nov 22 10:54AM -0800 Anyone have a copy of the operators manual (with schematics) for the Sencore Video Analyzer 48? I have the Speed Test Set-Up Booklet (physical, not PDF).   Trying to get mine running properly for servicing TVs used in video games from the early 70s.   Bitsavers, archive.org, and other online resources sources don't have this. The only ones I found were in a Google Drive link that has gone invalid.   As I track these down I will host them on TTL (Tech Tools List archive).   Thanks!   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."

Fox's Mercantile <jdangus@att.net>: Nov 21 03:53PM -0600 > based boards with zero board damage rate. Early paper > PCBs are somewhat notorious for tracks coming off when > heated.   If you lack the skills to do this, you're a hack. It's that simple. I've been doing this for 50 years now. I don't lift traces, or break off terminals unsoldering things.     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

bje@ripco.com: Nov 28 11:19AM > If the side that was higher is now lower and vice versa, you have an open > lamp(s) in the display. You might be able to find CCFL tubes on line to > replace them.     Thanks for passing along the info and it makes sense to me.   I didn't know the bulbs could go bad like that (even though when the set is on, the picture looks quite good with brightness and color temp).   I really doubt I'll proceed any further, I tried that lamp replacement once with a laptop and it didn't go well. Having all the different video inputs is handy but that really is the only thing going for it.   But since vga and dvi connections are becoming rare what is the point.   thanks again,   -bruce bje@ripco.com

"pfjw@aol.com" <peterwieck33@gmail.com>: Nov 27 09:39AM -0800 > Hook the fridge up to a surge protector.   Surge Protectors are designed to work on incoming power. Depending on the design, they are far less effective with outgoing surges. And, if you have, in fact, a drop in voltage due to a hard-start, the will have no effect at all.   Peter Wieck Melrose Park, PA

Cursitor Doom <curd@notformail.com>: Nov 28 08:53AM On Wed, 27 Nov 2019 06:43:28 -0800, bruce2bowser wrote:   > Hook the fridge up to a surge protector.   If it's the back EMF from the motor as I assume it will be, then it'll be a spike, not a surge, and that requires a different approach.           -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition.

Cursitor Doom <curd@notformail.com>: Nov 28 08:55AM > the design, they are far less effective with outgoing surges. And, if > you have, in fact, a drop in voltage due to a hard-start, the will have > no effect at all.   It's more likely a spike from the motor current being suddenly shut-off. Remember motors are reactive components.       -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition.

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