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Trevor Wilson <trevor@rageaudio.com.au>: Nov 30 07:07AM +1100 > This appears to be the only voltage source to this board.....   > Any ideas or suggestions?   > Thanks   **R601 is a 220 Ohm 0.5 Watt resistor. That is what is indicated on the schematic from Hi Fi Engine.   As others have stated, you need to use your noggin when fault-finding. For a 100k, 0.5 Watt resistor to show signs of stress (not burning) it would need to dissipate at least 0.5 Watt. That would suggest a Voltage drop in the order of 250 VDC across the resistor. Do you see 250VDC anywhere in that amp?   -- Trevor Wilson www.rageaudio.com.au

Jeff Urban <jurb6006@gmail.com>: Nov 29 11:19PM -0800 Another thing is they could have used a one ohm, or just nothing. But that resistor is actually not a fusible, it is a decoupling resistor. Look at test instruments, they will have 12V and 12VDCPL that only means there is a coil or resistor on there to isolate DCPL from ripple on the line, high or low frequency, DCPL means decoupled.   Most of them you can actually just jump out, but at 220 ohms it was probably meant to drop a few volts. But don't jump it out permanently.   Just jump it out and see if anything smokes or gets hot, if so that is usually the fault. If not then the resistor just went bad. It happens.

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tubeguy@myshop.com: Nov 29 06:13AM -0600 Its a Sansui 5050 receiver. The power amp works, the radio tuning meter moves, so it seems that works. But the preamp board is dead. Not a single transistor or any other component on that board has voltage. There is 44vdc on a wire from the power supply. It goes to a resistor. No voltage on other side of this resistor. Multimeter on ohm scale confirms resistor is open.   The problem is that resistor is red red brown @ 5% (gold). Thats 220 ohms. Yet an online schematic shows R601 as 100K.   OK, I know that resistor is dead, but how can the actual color code be so different from schematic? The resistor is not burnt, but may have gotten warm. Yet the color code is plain to see, except the gold band is kind of greenish.....   My plan is to clip in a resistor, but where do I start with such a conflict of values....   Yes, I triple checked this is R601. Unless the schematic is labeled wrong????   This appears to be the only voltage source to this board.....   Any ideas or suggestions?   Thanks

Fox's Mercantile <jdangus@att.net>: Nov 29 06:35AM -0600 > The problem is that resistor is red red brown @ 5% (gold). > That's 220 ohms. Yet an online schematic shows R601 as 100K.   Think about that for a minute. How is any of the 44 volts supposed to get though a 100K resistor and be able to do anything?   Replace the 220 ohm resistor with another 220 ohm.     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

John-Del <ohger1s@gmail.com>: Nov 29 04:36AM -0800 > This appears to be the only voltage source to this board.....   > Any ideas or suggestions?   > Thanks   Schematic errors are very common. We expect them and are never surprised by them.   100K won't deliver enough current to run a pre-amp board. If it is the B+ feed to the preamp, then it's going to be a much lower value resistor. Does the schematic show any voltages on the transistors that the 44V source feeds?

Fox's Mercantile <jdangus@att.net>: Nov 29 07:16AM -0600 On 11/29/19 6:36 AM, John-Del wrote: > 100K won't deliver enough current to run a pre-amp board.   The most it could deliver is 440 micro amps.   -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Tim Schwartz <tim@bristolnj.com>: Nov 29 08:37AM -0500 Looking at a schematic, there is an R601 on the F2646 Tone board (The one with the tone control pots) shown as a 220 ohm, 1/4 watt fuse resistor. There is a 100K R601 shown on the F2648 board schematic, but not the parts list, that I could find.   So, have a look at the manual and make sure you are looking at the diagram for the correct board, as there are (at least) TWO R601's in this unit. Or to quote a Canadian friend: "Clear as Mud, Eh?"   Regards, Tim Schwartz Bristol Electronics

Jeff Urban <jurb6006@gmail.com>: Nov 29 05:42AM -0800 The print I just got from hifiengine says it is 220 ohms.   There are errors all over the place, I have seen a lie, which represents a wire or PC foil as having 12 volts on one side and zero on the other.   You have to use your common sense. Look at the thing, how the hell could that be a 100K ? And where did you get that print ?   Sometimes it is bad if you don't catch it. I was fixing a Phase Linear 400-2 and the print had the emitter resistors as 0.22, but they were 0.33s. If I were to have put in 0.22s you know what would have happened ? Do you know how critical such resistors are ?   And then it would be a good idea to find out if something else blew that resistor, but the first step is to change it. Then you jump it out and get your voltage readings (compare channel to channel) and you could conceivably find some smoke to follow. And feel around, see if anything is hot.   Maybe even just jump it out first. Check for proper operation and any heat buildup. Ten when you put a resistor actually in there then watch the voltage drop across it, then ohm's law tells you if it is pulling a reasonable amount of current.   That resistor is not there as a fuse, it is there to isolate that circuit from power supply fluctuations.   Being a 220 ohm it is not as likely as resistors over 100K to open on their own, but it does happen. But it says half watt. That circuit should only pull a few milliwatts.

Rob <nomail@example.com>: Nov 29 02:33PM > supposed to get though a 100K resistor and be able to do > anything?   > Replace the 220 ohm resistor with another 220 ohm.   Better first find out why the other one blew. It is likely that a decoupling cap (tantalum?) downstream has failed.

Ralph Mowery <rmowery28146@earthlink.net>: Nov 29 11:24AM -0500 In article <aaa02c25-9a40-418c-b720-34d1f94bcc91@googlegroups.com>, jurb6006@gmail.com says...   > You have to use your common sense. Look at the thing, how the hell could that be a 100K ? And where did you get that print ?   > Sometimes it is bad if you don't catch it. I was fixing a Phase Linear 400-2 and the print had the emitter resistors as 0.22, but they were 0.33s. If I were to have put in 0.22s you know what would have happened ? Do you know how critical such resistors are ?   Companies are always making minor production changes that do not show up in the schematics. Going from .22 to .33 emitter resistors may not make a noticable change to most, but maybe someone with a very good ear could tell a difference.   I have seen service bullitens that come out and they tell to change a part to another value for various reasons. A 10 or 20 % change may not mean much to many, but going 10 or more times is often very noticable.   It would be very difficult to have 12 volts on one end of a wire and zero on the other that is the size of a PC board trace.

John-Del <ohger1s@gmail.com>: Nov 29 04:32AM -0800 > 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.     FWIW, lamp replacement on that display would be much easier than on a laptop display.   The big thing is to avoid damaging the ribbons between the LCD and the address board. They're easy to damage but also easy to not damage if you're just aware of them.   Relamping that old boy may allow another 10 years. Every TV hitting the market has a shorter life than the one it replaced. That's a fact.

whit3rd <whit3rd@gmail.com>: Nov 28 12:54PM -0800 On Thursday, November 28, 2019 at 12:55:40 AM UTC-8, Cursitor Doom wrote:   > It's more likely a spike from the motor current being suddenly shut-off. > Remember motors are reactive components.   A normal refrigerator motor turn-off doesn't have this effect. This is not normal, is most likely a wiring-in-the-walls fault. An electrician should check the power delivered.

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Cursitor Doom <curd@notformail.com>: Nov 23 01:37AM On Fri, 22 Nov 2019 07:54:53 -0800, Jeff Liebermann wrote:   > 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?   Thank you, Jeffrey. Not sure if you were able to read the thread right through, but it's been established that the blown cap was an X2 rated one fitted right across the incoming mains power line. It took a while to confirm this was the actual culprit as it was well buried under a load of spaghetti. When I finally got it out I was able to see it had literally exploded which accounts for the report I heard from 30' away. 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.       -- 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 24 12:02AM On Sat, 23 Nov 2019 08:27:56 -0600, Fox's Mercantile wrote:   > different things." > "The question is," said Humpty Dumpty, "which is to be master—that's > all."   I think I can see your problem now: you're a MORON.           -- 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.

Fox's Mercantile <jdangus@att.net>: Nov 24 10:23AM -0600 On 11/24/19 8:20 AM, Cursitor Doom wrote: > the network analyser I freely admitted to butchering earlier in the > thread?   > No Sherlock you, but blind as well as rude and ignorant, clearly.   Yes I did, that's why I said you're hack.     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Cursitor Doom <curd@notformail.com>: Nov 24 04:50PM On Sun, 24 Nov 2019 10:23:52 -0600, Fox's Mercantile wrote:   > Yes I did, that's why I said you're hack.   No, specifically you said and I quote: "I pointed out that you're a hack" which implies you have some sort of superior cognitive ability which the regulars here don't possess. Like as if everyone else needs an obnoxious *MORON* like you to spoon feed them the obvious!         -- 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 24 02:20PM On Sun, 24 Nov 2019 07:11:14 -0600, Fox's Mercantile wrote:   > That's precious. > I pointed out that you're a hack.   You're a *MORON* and a DUMBASS. Did you not see the picture I posted of the network analyser I freely admitted to butchering earlier in the thread?   No Sherlock you, but blind as well as rude and ignorant, clearly.       -- 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.

Fox's Mercantile <jdangus@att.net>: Nov 24 02:24PM -0600 On 11/24/19 10:50 AM, Cursitor Doom wrote: > which implies you have some sort of superior cognitive ability which the > regulars here don't possess. Like as if everyone else needs an obnoxious > *MORON* like you to spoon feed them the obvious!   And there you have it... You're a hack. You just said so yourself.       -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Fox's Mercantile <jdangus@att.net>: Nov 25 02:22PM -0600 On 11/25/19 1:09 PM, Ralph Mowery wrote: > back inside the car. Took a hole saw on a drill and cut a hole. > Replaced the plug , pop rivited a beer can cutout over the hole and > replaced the carpet.   That's a clever repair. I did the same thing on a '68 Dodge station wagon. The freeze plug on the rear of the cylinder heads. Cut a hole, or pull the intake and the heads. Obvious choice.   WHEN you work on your own vehicle. You have next to zero funds and you need to drive it into work the next day.   Had I had the time, I would have pulled the engine and replaced all the freeze plugs at the same time instead of one at a time.   I had the time over the weekend, and that's exactly what I did. including pulling the flywheel and getting the two behind it.             -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Fox's Mercantile <jdangus@att.net>: Nov 25 03:05PM -0600 > Cut a hole, or pull the intake and the heads. Obvious choice.   > Care to speculate, as I asked Ralph, on the consequences?   As to the operation of the cooling system? No difference of doing it right. The plug was installed correctly using an installation tool. To the vehicle itself? A Campbell's soup can lid pop riveted to the firewall over the hole I cut. Complete with some sealant to properly seal the firewall.   However, I might add, that the following weekend, I pulled the engine out and replaced the rest of the freeze plugs. Because I didn't want any more trouble with them.       -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Ralph Mowery <rmowery28146@earthlink.net>: Nov 25 02:09PM -0500 In article <JrednUxVUfnRCEbAnZ2dnUU7-SednZ2d@giganews.com>, jdangus@att.net says... > He has finally admitted to being a hack. > I said you were a hack. > I stand by my observation.   Sometimes it takes a hack to get the job done at a reasonable cost.   Like a car company wanted lots of money to replace a freeze plug on a car engine. Due to where it was placed , they said the motor needed to be pulled.   A local hack said he could do it for almost nothing. Pulled the carpet back inside the car. Took a hole saw on a drill and cut a hole. Replaced the plug , pop rivited a beer can cutout over the hole and replaced the carpet.

Al <iqbalali898@noreply.com>: Nov 26 12:08AM > Care to speculate on the horrific consequences of that particular > "hack"?   Yeah, I should imagine the possibility of a slight draft in the area of the footwell that side. Just maybe... But that's all.

Mike Coon <gravity@mjcoon.plus.com>: Nov 26 09:37AM In article <MPG.384642a55dafaf14989c5a@news.east.earthlink.net>, rmowery28146@earthlink.net says...   > I doubt a 3 inch in diameter how would cause any real problem. It would > have cost more than the car was worth anyway if the motor had to be > pulled.   When I was a student I shared rides in a car with a hole in the floor on the passenger side. The trick was to keep your foot on the hole to avoid when going through any puddle getting a jet of water up your trouser leg.   We probably could not afford a pop-riveter and sealant, and the beer may have come in bottles. Wet carpets are no fun, either...   Mike.

Cursitor Doom <curd@notformail.com>: Nov 23 01:40AM On Fri, 22 Nov 2019 04:22:06 -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.   You can call me a hack as well if you like; I couldn't give a shit TBH. I'm not very practical. I get the job done but it doesn't look as pretty as some genius like yourself would leave it. But do I care? Nope! Because the case goes back on and no one can see it anyway.         -- 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 24 10:08AM On Sat, 23 Nov 2019 18:54:28 -0600, Fox's Mercantile wrote:   > On 11/23/19 6:02 PM, Cursitor Doom wrote: >> I think I can see your problem now: you're a MORON.   > Do you honestly believe I give a flying fuck what you think?   Just pointing it out for the benefit of others here who may not yet be fully familiar with your profane outpourings of ill-informed garbage and propensity to discharge same.       -- 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.

Fox's Mercantile <jdangus@att.net>: Nov 24 02:22PM -0600 > life's too short for this much childishness. Sorry.   And yet you persist.   -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Cursitor Doom <curd@notformail.com>: Nov 25 10:12PM On Sun, 24 Nov 2019 22:10:44 -0800, tabbypurr wrote:   > he's aping slowman.   Just plain aping. I find it impossible to believe that anyone could *genuinely* be that stupid. Hence my deduction he's a troll - and now one of the very few posters I've felt it necessary to perma-plonk. Just think of all that valuable future time I've saved myself by avoiding further futile and infantile exchanges from him. >:-}       -- 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.

Fox's Mercantile <jdangus@att.net>: Nov 23 08:18AM -0600 >> Sure you did. You asked *me* "...how you (meaning me) remove caps from paper based boards with zero board damage rate."   >> This indicates you can't.   > yawn   To a hammer, everything looks like a nail. To a hack, everything looks like a can't.     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Cursitor Doom <curd@notformail.com>: Nov 23 04:45PM On Sat, 23 Nov 2019 18:08:11 +1100, marty wrote:   > It's cactus, throw the thing out.   I don't believe in doing that unless there's no other option. Having grown up in the overhang of postwar rationing and austerity I feel compelled to do all I can to rescue stuff if it's safe and practical to do so. Plus our 'throw away society' is not doing the planet any favours at all.       -- 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 23 06:04PM On Fri, 22 Nov 2019 22:34:01 -0800, whit3rd wrote:   > It's either an energency overtemperature cutoff (like a fuse), or a > thermal switch that repeatedly time-cycles according to the > heating/cooling time constant of its companion resistors.   I assumed it was tucked between those resistors to sense any higher than usual warming in them. It's marked 76 degrees C in the case of this one. I'm guessing it (since it's in series with the live line) that if the temp rises above that level it will wind back the current, but this one has blown completely open-circuit and maybe that's what it was designed to do. Nothing visible, just on testing for resistance.   > 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).   Sounds feasible. I'll check the resistance of the heating elements and see what they show. One may have gone partially short-circuit, causing the fault in the first place. It's a 70W blanket so at 240V they should come out at about 800 ohms in total if my quick 'n' dirty sums are correct.       -- 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 25 10:05PM On Mon, 25 Nov 2019 07:57:16 +0200, Mikko OH2HVJ wrote:     > The turns are there for pliers or other tool to absorb the heat while > soldering the thermal fuse to the PCB. It's quite easy to blow a low > temperature rating thermal fuse while soldering.   Ah, thanks very much for that, Mikko; the missing piece in the jigsaw!   > What't the schematic like, are the resistors connected in such a way > that they would heat during some failure condition and blow the fuse ?   I don't have a schematic, but that's been my working assumption throughout. It makes sense that way.       -- 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.

Starfella <starfella@starfella.net>: Nov 22 06:49PM -0500 On 11/22/19 2:50 PM, Cursitor Doom wrote:   > Question is, what is the correct name for this 'mystery component' and > what should it read resistance-wise when cold?   > Thanks!   Not sure about the name of the component, but I will say that today's electric blankets are awfully poor made. Years ago, when I had one while growing up, it lasted for at least 10 years before someone threw it away during cleaning. As an adult, I purchased a Sunbeam brand about five years ago and I've never had one last more than 6-8 weeks! The only type of heating blanket I've found in recent times that does last are electric throws. I have two, purchased about 5 years ago, and with heavy use, they still work fine. Problem is that they are a bit too small for bed use although I make them work that way.

bje@ripco.com: Nov 26 11:30AM > Have you done anything with the settings? Most TVs come from the factory > on "display mode" with all settings at maximum. Which, of course would max > out the power-supply.     Hmmm, I dunno about this, it's one thing to max out a power supply and another to cause parts to smoke and burn. Me thinks Samsung would have a few lawsuits to deal with just because someone enjoyed "vivid".   The set has had a hard life and there is really no tears here. Like I mentioned, it's been in use for the past 10+ years, usually on for 12-15 hours a day (usually background noise).   The only reason it's not in the trash yet is 1) it's a native 1080p in a small package (25") which doesn't seem to be made anymore and 2) it has just about any video input you need, hdmi, dvi, vga, component and composite.   The sad part about all of this is I replaced it with a 32" Sanyo that Microcenter was blowing out for $49.95, less than the parts I spent trying to fix the Samsung.   -bruce bje@ripco.com

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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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whit3rd <whit3rd@gmail.com>: Nov 26 11:35AM -0800 On Sunday, November 24, 2019 at 5:33:08 PM UTC-8, Paul Drahn wrote:   > >>>>>> but maybe I can decipher it anyway.     > Just be aware that sometimes trash is included in EPROMS to stop what > you are trying to do!   Three things to look out for: the ordering of the data bits can be scrambled; probably you can trace those to the CPU pins the ordering of the address bits can be scrambled, and some may be hard to trace to the CPU pins the data and/or the address might go through inverting transceivers, which changes the bit-is-a-one /bit-is-a-zero identity.

Tim R <timothy42b@aol.com>: Nov 27 06:46AM -0800 > 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'm sure you know this but I've been bitten once and it may be worth mentioning.   I understand you're trying to back up your EPROM holding your program. We had a similar problem in a manufacturing plant, probably with an Allen Bradley PLC or similar. (it's been a while) The program went bad, we got the backup EPROM, and uploaded the saved program.   Except we didn't. The wording of upload and download was ambiguous and we accidentally saved the bad program from the machine onto the EPROM. We had one extra EPROM in the safe, got that out and ………… did exactly the same thing.   Everything was ladder logic and I came to hate those hardcopy printouts, but with enough time and patience we could type it back in. Ladder logic was theoretically understandable to the electricians but it violates every single concept in programming. Every line can refer to any other line - no modular programming, no single entry single exit, etc.

bruce2bowser@gmail.com: Nov 27 06:43AM -0800 >> Thank you !   >A surge protector has only limited effectiveness on "outgoing" surges. Not none, > limited.   Hook the fridge up to a surge protector.

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bje@ripco.com: Nov 26 11:30AM > Have you done anything with the settings? Most TVs come from the factory > on "display mode" with all settings at maximum. Which, of course would max > out the power-supply.     Hmmm, I dunno about this, it's one thing to max out a power supply and another to cause parts to smoke and burn. Me thinks Samsung would have a few lawsuits to deal with just because someone enjoyed "vivid".   The set has had a hard life and there is really no tears here. Like I mentioned, it's been in use for the past 10+ years, usually on for 12-15 hours a day (usually background noise).   The only reason it's not in the trash yet is 1) it's a native 1080p in a small package (25") which doesn't seem to be made anymore and 2) it has just about any video input you need, hdmi, dvi, vga, component and composite.   The sad part about all of this is I replaced it with a 32" Sanyo that Microcenter was blowing out for $49.95, less than the parts I spent trying to fix the Samsung.   -bruce bje@ripco.com

"pfjw@aol.com" <peterwieck33@gmail.com>: Nov 26 04:42AM -0800 > Hmmm, I dunno about this, it's one thing to max out a power supply and > another to cause parts to smoke and burn. Me thinks Samsung would have a few > lawsuits to deal with just because someone enjoyed "vivid".   That would be the fallacy of "Leaping to Conclusions", with a smattering of "begging the question" thrown in.   Try the settings, and see if that does not cool things down. If not, you are no worse off. If so, enjoy it for a few more years.   Peter Wieck Melrose Park, PA

John-Del <ohger1s@gmail.com>: Nov 26 05:17AM -0800 > Any guesses?   > -bruce > bje@ripco.com   Bad lamps. Most CCFL inverters shut down when a defective lamp is encountered and I am very surprised this one doesn't. It won't be a shorted lamp but a lamp(s) that are weak and require more voltage to deliver the current the inverter transformer is designed to deliver.   That board has a single output transformer, but it has two secondaries. A way to check this is to turn the TV on and put your scope probe *NEAR* the output harnesses or connector and watch the waveforms. Use a high vertical input setting and a fast horiz setting. Make sure to place the probe in the same relative position to the connector on both sides as the physical placement of the probe changes the amplitude greatly.   Don't connect the probe electrically to the inverter unless you were planning to buy a new scope anyway...   Now, one of the two waveforms will be much higher than the other, maybe twice as high. The actual amplitude isn't important because you're only looking for differences between the two sides, not taking p-p measurements.   Mark which side is higher, then see if you can switch the two harnesses and try again. You'll probably have to flip the board over to do this so make sure you put down an insulator between the board and TV frame because those heatsinks could be at hot ground potential.   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.

Ralph Mowery <rmowery28146@earthlink.net>: Nov 25 02:09PM -0500 In article <JrednUxVUfnRCEbAnZ2dnUU7-SednZ2d@giganews.com>, jdangus@att.net says... > He has finally admitted to being a hack. > I said you were a hack. > I stand by my observation.   Sometimes it takes a hack to get the job done at a reasonable cost.   Like a car company wanted lots of money to replace a freeze plug on a car engine. Due to where it was placed , they said the motor needed to be pulled.   A local hack said he could do it for almost nothing. Pulled the carpet back inside the car. Took a hole saw on a drill and cut a hole. Replaced the plug , pop rivited a beer can cutout over the hole and replaced the carpet.

"pfjw@aol.com" <peterwieck33@gmail.com>: Nov 25 12:16PM -0800 Care to speculate on the horrific consequences of that particular "hack"? And I doubt if those consequences are specific to the US.   Peter Wieck Melrose Park, PA

Fox's Mercantile <jdangus@att.net>: Nov 25 02:22PM -0600 On 11/25/19 1:09 PM, Ralph Mowery wrote: > back inside the car. Took a hole saw on a drill and cut a hole. > Replaced the plug , pop rivited a beer can cutout over the hole and > replaced the carpet.   That's a clever repair. I did the same thing on a '68 Dodge station wagon. The freeze plug on the rear of the cylinder heads. Cut a hole, or pull the intake and the heads. Obvious choice.   WHEN you work on your own vehicle. You have next to zero funds and you need to drive it into work the next day.   Had I had the time, I would have pulled the engine and replaced all the freeze plugs at the same time instead of one at a time.   I had the time over the weekend, and that's exactly what I did. including pulling the flywheel and getting the two behind it.             -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

"pfjw@aol.com" <peterwieck33@gmail.com>: Nov 25 12:30PM -0800 Cut a hole, or pull the intake and the heads. Obvious choice.   Care to speculate, as I asked Ralph, on the consequences?   Peter Wieck Melrose Park, PA

Fox's Mercantile <jdangus@att.net>: Nov 25 03:05PM -0600 > Cut a hole, or pull the intake and the heads. Obvious choice.   > Care to speculate, as I asked Ralph, on the consequences?   As to the operation of the cooling system? No difference of doing it right. The plug was installed correctly using an installation tool. To the vehicle itself? A Campbell's soup can lid pop riveted to the firewall over the hole I cut. Complete with some sealant to properly seal the firewall.   However, I might add, that the following weekend, I pulled the engine out and replaced the rest of the freeze plugs. Because I didn't want any more trouble with them.       -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

"pfjw@aol.com" <peterwieck33@gmail.com>: Nov 25 03:03PM -0800 Nope. Care to try again?

Al <iqbalali898@noreply.com>: Nov 26 12:08AM > Care to speculate on the horrific consequences of that particular > "hack"?   Yeah, I should imagine the possibility of a slight draft in the area of the footwell that side. Just maybe... But that's all.

Ralph Mowery <rmowery28146@earthlink.net>: Nov 25 07:58PM -0500 In article <qrhqda$roo$3@dont-email.me>, iqbalali898@noreply.com says... > > "hack"?   > Yeah, I should imagine the possibility of a slight draft in the area of > the footwell that side. Just maybe... But that's all.   No draft, covered by the cut up beer can and carpet.   I doubt a 3 inch in diameter how would cause any real problem. It would have cost more than the car was worth anyway if the motor had to be pulled.

Mike Coon <gravity@mjcoon.plus.com>: Nov 26 09:37AM In article <MPG.384642a55dafaf14989c5a@news.east.earthlink.net>, rmowery28146@earthlink.net says...   > I doubt a 3 inch in diameter how would cause any real problem. It would > have cost more than the car was worth anyway if the motor had to be > pulled.   When I was a student I shared rides in a car with a hole in the floor on the passenger side. The trick was to keep your foot on the hole to avoid when going through any puddle getting a jet of water up your trouser leg.   We probably could not afford a pop-riveter and sealant, and the beer may have come in bottles. Wet carpets are no fun, either...   Mike.

"pfjw@aol.com" <peterwieck33@gmail.com>: Nov 26 04:01AM -0800 OK. To attempt to get you all to think "outside the box".   Question: Why do we stop at STOP signs, even when there is no one else (visible) around?   You park your car on a hill. You neglect to turn your wheels to the curb. Some kid sees change in your cup-holder and breaks into the car, meanwhile releasing the parking brake. The car rolls down the hill and hurts someone. Who is responsible?   Now, consider that hole in that firewall. Please try to think it through.   Peter Wieck Melrose Park, PA

John-Del <ohger1s@gmail.com>: Nov 26 04:53AM -0800 > Now, consider that hole in that firewall. Please try to think it through.   > Peter Wieck > Melrose Park, PA   You're going to hate this story Peter: I had an old Explorer that had a bad fuel pump. This truck was originally sold near the shoreline and and had suffered almost 20 years in the rust belt. There was no chance of getting the fuel tank down without fighting through rusted hardware and other issues, so I got out my nibbler and opened an access hole under the back seat right over the fuel pump flange. 90 min in an out.

"pfjw@aol.com" <peterwieck33@gmail.com>: Nov 26 04:59AM -0800 On Tuesday, November 26, 2019 at 7:53:27 AM UTC-5, John-Del wrote:   > > Peter Wieck > > Melrose Park, PA   > You're going to hate this story Peter: I had an old Explorer that had a bad fuel pump. This truck was originally sold near the shoreline and and had suffered almost 20 years in the rust belt. There was no chance of getting the fuel tank down without fighting through rusted hardware and other issues, so I got out my nibbler and opened an access hole under the back seat right over the fuel pump flange. 90 min in an out.   Which is not the firewall. And, there are actual after-market hatches for that application. Which are not made from aluminum beer-cans and aluminum pop-rivets.   https://www.summitracing.com/parts/tnk-ad-66?seid=srese1&gclid=Cj0KCQiAt_PuBRDcARIsAMNlBdoNrWes9c1ZaHtW5jN_Qigc5WOsWbm7rhtW3ItFjgIdTLDofkTwwZQaAvnoEALw_wcB   Peter Wieck Melrose Park, PA

Cursitor Doom <curd@notformail.com>: Nov 25 10:12PM On Sun, 24 Nov 2019 22:10:44 -0800, tabbypurr wrote:   > he's aping slowman.   Just plain aping. I find it impossible to believe that anyone could *genuinely* be that stupid. Hence my deduction he's a troll - and now one of the very few posters I've felt it necessary to perma-plonk. Just think of all that valuable future time I've saved myself by avoiding further futile and infantile exchanges from him. >:-}       -- 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.

Fox's Mercantile <jdangus@att.net>: Nov 25 04:46PM -0600 On 11/25/19 4:12 PM, Cursitor Doom wrote: > of the very few posters I've felt it necessary to perma-plonk. Just think > of all that valuable future time I've saved myself by avoiding further > futile and infantile exchanges from him. >:-}   I guess you lied about kill filing me.       -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Cursitor Doom <curd@notformail.com>: Nov 25 10:05PM On Mon, 25 Nov 2019 07:57:16 +0200, Mikko OH2HVJ wrote:     > The turns are there for pliers or other tool to absorb the heat while > soldering the thermal fuse to the PCB. It's quite easy to blow a low > temperature rating thermal fuse while soldering.   Ah, thanks very much for that, Mikko; the missing piece in the jigsaw!   > What't the schematic like, are the resistors connected in such a way > that they would heat during some failure condition and blow the fuse ?   I don't have a schematic, but that's been my working assumption throughout. It makes sense that way.       -- 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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