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etpm@whidbey.com: Nov 15 03:57PM -0800 On Fri, 15 Nov 2019 13:48:51 -0800, John Robertson <spam@flippers.com> wrote:   >can do this in my shop, but I suspect we are not very close - I'm in >Vancouver (Burnaby, but no one knows that city), Canada area...   >John It's a Fanuc control and as far as I know the control is completely Fanuc. I don't know anyone who has s Fluke 9010 and even though I know where Burnaby is it is still a bit of a drive from the south end of Whidbey Island. I do have other 2516 EPROMs that are useless to me that I am going to use to test the reader/programmer. The tech support guy did say that 2516 devices may not program properly but that they can be read just fine. Nevertheless I will take your advice. I can use my TEK 465B scope to check the voltages. And I read either here or in an email from the tech support folks that the TI 2516 devices are the same as the 2716 devices and I know that at least one EPROM is a TI 2516. There is a mix of devices because it seems that at least two EPROMs are common to almost every board from Miyano lathes and the other 4 on the one board are the ones I need to copy. So as I buy old boards I get, now and then, copies of the two common types. So these will be tested first along with some other 2516 devices I have from another Fanuc control. I really appreciate all the advice I get here and especially the EPROM advice I am getting recently. It really makes me feel better about repairing this machine. Speaking of this lathe, I know people who would say just replace the machine or at least the control. But I have done a complete control replacement before and it is not trivial. And Fanuc controls are usually very robust. It is just this one board that is giving me problems and I can't see how the machine itself could be damaging this particular board. I could just replace the machine completely but this is very expensive and this particular machine is just not getting enough work at this time to justify at least 60 grand to replace it. The lathe itself is, the mechanics and the servos, are in great shape. I can hold .0001" without any problems. All day. Even though the top spindle speed is only 5000 RPM most of the work I do can't be done at higher RPM because of the diameter and material of the work. Eric

John-Del <ohger1s@gmail.com>: Nov 16 03:46PM -0800 > > If you know the board *will* be fixed and put back in service, then yes, by all means replace them. But if I pull an electro during testing and it's good, I put it back and continue working on the board. No sense changing good caps on a board that may have to be replaced, like OP is dealing with.   > > Lots of these industrial boards use custom ICs, ICs and semis that have been intentionally defaced, and processor ICs for which there is just no data. Sometimes you just have to replace a board.   > 'lytic caps go bad eventually. After removing the caps for testing you've already run the risk of damaging the board.       Anyone who would ruin a board by removing a cap isn't a professional and shouldn't be playing with it. There is ZERO chance of damaging even a multi-layer board.       >Why put the old ones back? In broadcast gear small value caps are the most common failures. I've replaced thousands of 100uF 25 V caps. Unit price 32 cents, 1000 for $83. Buy in bulk and replace in bulk. It costs less than testing and re-installing.       You actually quoted my reason (thanks for not snipping it) but either didn't read it or didn't understand it. So I've copied and pasted my previously posted reason below:   "If you know the board *will* be fixed and put back in service, then yes, by all means replace them. But if I pull an electro during testing and it's good, I put it back and continue working on the board. No sense changing good caps on a board that may have to be replaced, like OP is dealing with."   "Lots of these industrial boards use custom ICs, ICs and semis that have been intentionally defaced, and processor ICs for which there is just no data. Sometimes you just have to replace a board."     So if I have to replace a board that caps won't fix, why go through the trouble of recapping it? On low to mid percentage shots like these one-off industrial controls, the plan is five stages:   1)I troubleshoot and repair the board first. If it's not repairable, I go to step 5. If I get the board repaired, I go to step 2.   2)recap it   3)Clean and deflux the board, and inspect under a bright light and loop. Reflow any questionable solder and reflow all the solder on edge connectors, transformers, and high heat generating components.   4)Deflux again and spray with conformal coating if the board originally was built with it.   5)Get paid for my time.

John-Del <ohger1s@gmail.com>: Nov 16 03:51PM -0800 On Saturday, November 16, 2019 at 11:09:21 AM UTC-5, Ralph Mowery wrote:   > > G   > Right, at the small cost of the capacitors, it is foolish to put backin > an old one even if the board may have other problems and not used.     I've read that sentence like 5 times and all I can say is that you wouldn't be working for me..   Honestly, sometimes I wonder if people just post because they want to say *something*.

Cursitor Doom <curd@notformail.com>: Nov 17 12:43AM On Sat, 16 Nov 2019 15:46:48 -0800, John-Del wrote:   > Anyone who would ruin a board by removing a cap isn't a professional and > shouldn't be playing with it. There is ZERO chance of damaging even a > multi-layer board.   There is when *I'm* around! Here's how I got an inaccessible cap out of this network analyser a couple of days ago: https://postimg.cc/bZYGSvnr   But as you will probably gather, I'm no professional. :-D         -- 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.

Ralph Mowery <rmowery28146@earthlink.net>: Nov 16 07:43PM -0500 In article <09a27d80-f256-4077-a76f-9fcb6a9ba433@googlegroups.com>, ohger1s@gmail.com says...   > I've read that sentence like 5 times and all I can say is that you wouldn't be working for me..   > Honestly, sometimes I wonder if people just post because they want to say *something*.   I doubt that I would work for a tightwad like you. If those capacitors are less than one dollar, it will take more time to test and replace them than the labor would pay.   Lets say I just make $ 20 per hour. It may take me 5 minuits to setup the capacitor checker and test it. That would be about 33 cents. If the capacitor was a dollar, you have saved 77 cents.   However if the board is good, I have to pull that capacitor and replace it anyway. How long would that take and what would it cost ?   You have just lost money on that capacitor you thought you were saving.

Cursitor Doom <curd@notformail.com>: Nov 17 12:57AM On Sat, 16 Nov 2019 15:46:48 -0800, John-Del wrote:   > So if I have to replace a board that caps won't fix, why go through the > trouble of recapping it?   I'm worried about cheap Chinese crap getting into the supply chain and that's why I'd rather leave things be. I might end up replacing a perfectly serviceable 40 year old cap made by a prime manufacturer with something nasty from China that's going to go *phut* long before the original one would have.       -- 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.

Ralph Mowery <rmowery28146@earthlink.net>: Nov 14 05:35PM -0500 In article <68crset030lbht7eq52p34vogu6lmvqj61@4ax.com>, etpm@whidbey.com says... > one electrolytic capacitor. I have checked this cap on two boards with > my meter and the cap has the stated value and is not shorted. But I > don't have a way to check ESR.   The capacitor probably only costs a few dollars at most. Just replace it and see if the board comes back to life. That is see if the machine acts normally.

etpm@whidbey.com: Nov 14 04:01PM -0800 On Thu, 14 Nov 2019 17:35:48 -0500, Ralph Mowery   >The capacitor probably only costs a few dollars at most. Just replace >it and see if the board comes back to life. That is see if the machine >acts normally.   Yeah, I am gonna do that. I just won't get my hopes up. Eric

etpm@whidbey.com: Nov 14 04:01PM -0800 On Thu, 14 Nov 2019 13:03:28 -0800, John Robertson <spam@flippers.com> wrote:   >gun and some cold spray may help find the sensitive IC as you say the >problem goes away when the system is warm.   >John :-#)# Greetings John, Actually the machine starts to work after it has warmed up for a while. I have tried the whole contact cleaning route several times and it has had no effect on this machine. Today I tried out two boards that I got used from eBay. One worked and the other, whil it indexed then turret OK would not allow programmed speed changes. The speed change fault is mysterious to me and it has happened on another board. The mystery is because of what the fault does. Niormally speed changes while running a program can only happen from programmed speed changes or from the constant surface speed command. But when the board goes bad then the spindle speed can only be controlled by the dial used for speed changes when in jog mode. And that dial normally does not work when running a program. I checked all the parameters and they have not changed. And the EPROMs that hold the ladder programs for the machine are not affected. In fact, I have to change them from board to board. Speaking of EPROMs, I am ordering a GQ-4x4 programmer so I can copy my EPROMs. I am really afraid I will destroy one one of these days. I have lots of 2716 and 27C16 EPROMs that I can erase and re-program. The machine has in it some 2716 and 2516 devices and I was told that the 2516 devices should not be used. I am hoping the programmer can read the 2516 devices. Thanks, Eric

etpm@whidbey.com: Nov 14 12:20PM -0800 One of my CNC machines has a circuit board that has failed 3 times now. The control is a FANUC 3T. It is an older control so failing boards don't surprise me. But it is just the one board. This board has many custom hybrid ICs, some other of the shelf ones, 6 EPROMs, and one electrolytic capacitor. I have checked this cap on two boards with my meter and the cap has the stated value and is not shorted. But I don't have a way to check ESR. The failure mode for all the boards is the same. First the turret on this lathe will occasionally index in the wrong direction. After the machine is powered up for a while it will then start to index properly. I can control the turret rotation from a program but when the board starts to fail it will only index in one direction. Furthermore, then turret should always rotate in the direction that is the shortest to the next tool called up, but when the board starts going bad the turret still only indexes in one direction. Unfortunately this is the wrong direction. After this failure other things start going wrong, like the speed control. Changing the boards has always fixed the problem. Note that when I change the boards I have to swap all the EPROMs so that the programming for the machine operation will be the same. Since all the boards seem to fail the same way I was wondering if somehow a failing cap could cause this failure. Even though the cap value reads fine with my VOM, that does not measure ESR. In any case I'm gonna order some caps and see if anything changes but I would like to know if it is probably gonna be a waste of time. Thanks, Eric

Cursitor Doom <curd@notformail.com>: Nov 15 09:40AM On Thu, 14 Nov 2019 18:32:29 -0800, John-Del wrote:   > 99% of the time a board that works normally when heated has a lazy > electrolytic.   Or a dry solder joint somewhere on the board.   > If the electro replacement doesn't fix it, try cooling individual parts > to see if you can get it to act up.   Good call. For which you can use stuff like 'pipe freeze' or 'Arctic freeze' with the fine straw inserted - sold at your local plumbing supplies. Clean the board with IPA afterwards.         -- 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 15 09:45AM On Thu, 14 Nov 2019 18:32:29 -0800, John-Del wrote:     > If so, the first thing to get checked is the electros. I pull every one > and test them for value, ESR, and dielectric absorption. Testing ESR in > circuit on many modern circuit boards is a waste of time.   Why so?       -- 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 14 08:24PM -0600 > 1234   > Server Issues?   UR 5X9 NTX, QSL?       -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Cursitor Doom <curd@notformail.com>: Nov 14 11:42PM On Sun, 10 Nov 2019 18:37:41 -0800, Michael Terrell wrote:   > leaving the remaining part of the capacitor, in circuit. If you measure > the capacitance of a damaged X or Y capacitor, it will be lower than > marked.   Yeah, I guess it would. Anyway, after hacking a hole in the bottom of the motherboard I was able to removed the cap in question from underneath and it looks far worse now I can see it properly. It definitely let go in a big way and now I'm pretty confident it was the source of the loud bang I heard. I've also carefully examined all the other sub-boards and the PCB underneath them and they're all fine. Shards of broken cap were scattered about the area of the explosion. Shame I had to butcher the board to get it out, but there was no other way open to me. I follow what you said about removing that j6 power connector but I just don't have the dexterity I'm afraid. So it was a case of Dremmel to the rescue! :-)

Ralph Mowery <rmowery28146@earthlink.net>: Nov 16 11:16AM -0500 In article <3172fcc8-cfa4-4313-ae22-b23bc9d8300e@googlegroups.com>, timothy42b@aol.com says...   > A dehumidifier should be heat neutral as you say.   > I?m not so sure about the process. A phase change is involved, when water goes from gas to liquid it has to dump all that phase change energy.   > I use a dehumidifier in the basement. If you figure out how to make one last more than 2 years let me know.   The dehumidifiers in homes do produce some heat from the motors. Not much, but some. Then if you have to empty the water by hand, you are not loosing heat by the water to ammount to anyting.   Many people do not get very many years out of their dehumidifires. Looks like they should as they are nothing much more than a refrigerator with an open door or even an airconditioner.   I have not thought about it , but I wonder if you put a window AC in a room and a drain bucket under it if it would not be just as good as the dehumidifier and last longer.   I think the newer ones do use the splash from the condenced water to help cool the coils.

amdx <nojunk@knology.net>: Nov 16 12:08PM -0600 On 11/16/2019 10:16 AM, Ralph Mowery wrote:   > The dehumidifiers in homes do produce some heat from the motors. Not > much, but some. Then if you have to empty the water by hand, you are > not loosing heat by the water to amount to anything.   I have found several sites that either complain about the extra heat produced by a dehumidifier or explain why they produce heat.   Dehumidifiers are over unity heat producers with a 1.5 COP.   My dehumidifier was recalled as a fire hazard, had to send in the cutoff power cord. I'm tempted to reinstall a cord, run and then measure the temperature of the condensate to see if heat is removed and how much. It may not be much as I have seen that as part of the calculation. I thought it was applicable and still not sure it isn't. Mikek

amdx <nojunk@knology.net>: Nov 16 10:16PM -0600 On 11/16/2019 12:08 PM, amdx wrote:   >> https://www.allergyconsumerreview.com/dehumidifiers-answer.html   Must have gotten rid of the recalled Dehumidiier, if anyone has a running dehumidifier could you check the temperature of the condensate and see how it compares to the air temp. I suppose it has to be cold if it is dripping off the condenser coil, the question is how long does it have to re-absorb heat from the room, or is it dumped down the drain or run outside.

amdx <nojunk@knology.net>: Nov 14 12:20PM -0600 > taken into account too. > Thanks, > Eric   Can you add enough positive pressure to the basement to reduce the flow down the stairs? I know that would be drawing cold air into the basement. ¯\_(ツ)_/¯ Get a dehumidifier, you get heat and dry air.   Mikek

Adrian Caspersz <email@here.invalid>: Nov 14 06:34PM > moisture in the basement room. I want to keep the room cool so heating > to get rid of the moisture is out. So I have been looking at vent fans > and pretty much all I see are fans for venting crawl spaces and   Seems you need to block the air coming down the stairs. Is there a door at the top? Can you install another a few feet in like an air lock, and vent out the air in-between with a timer/humidity operated fan?   -- Adrian C

Jim Horton <jhorton@nospam.net>: Nov 12 03:09PM -0500 Took forever to wait on the broken fan for containment of the charcoal, but it's finally done and filtering the air well. I feel confident that with the wet filters and the activated charcoal, it will do well with the solder smoke. I've been testing it in some musty/ smelly rooms in the house and, within an hour, the odors are cleared. As incense is burned, it draws in the smoke and no odor that I can detect. I suppose that will probably lessen the activated charcoal's life a bit. However, for just under $20, I'm pretty happy. Thanks again for the help and suggestions here.

Clive Arthur <cliveta@nowaytoday.co.uk>: Nov 14 05:17PM On 13/11/2019 01:33, Winfield Hill wrote:   >> ... within an hour, the odors are cleared. As incense is >> burned, it draws in the smoke and no odor that I can detect.   > But then, why burn the incense in the first place?   To ward off the twin evil spirits of decaffeinated coffee and alcohol-free beer.   Cheers -- Clive

Chris <cbx@noreply.com>: Nov 14 11:34PM OK, thanks to everyone who responded. I'd thought that volume feature would be unique to one manufacturer to be honest - I've never seen it on any other amp. I think now someone mentioned JVC and that *does* ring a bell. It's just that I'd never equated JVC with the best of the amps of that era. Looks like I may have to review my prejudices. The search goes on...

kermitjohnson@protonmail.com: Nov 16 09:42AM -0800 Received a Insignia NS-24E40SNA14 24" Class LED HDTV LCD HD TV because the power supply got lost in moving.   Googled to check if could find either the Insignia TV Service Manual or just the Schematic but to date have found neither. Did find a photo for the video board but the resolution was too low to be of help.   Have also read the comments for this TV and wonder if the original power supply is adequate? https://www.insigniaproducts.com/pdp/NS-24E40SNA14/9844485   Am interested in any recommendations how to find either Service Manual or Schematic.   Am also thinking if could find OEM maybe the same TV is or was available under a different name.

abrsvc <dansabrservices@yahoo.com>: Nov 16 02:04PM -0800 Not sure where you are, but the following listing is for an entire set for short money($25.95 to start). Maybe this is an option?   Dan   https://www.ebay.com/itm/Insignia-24-Inch-TV-1080p-Model-Number-Ns-24E40SNA14/153722498750?hash=item23ca932ebe:g:d0wAAOSwZTldyxmy

Phil Allison <pallison49@gmail.com>: Nov 16 02:40PM -0800 kermit...@protonmail.com wrote:   -------------------------------   > Googled to check if could find either the Insignia TV Service Manual or just the Schematic but to date have found neither. Did find a photo for the video board but the resolution was too low to be of help.   > Have also read the comments for this TV and wonder if the original power supply is adequate? https://www.insigniaproducts.com/pdp/NS-24E40SNA14/9844485   > Am interested in any recommendations how to find either Service Manual or Schematic.   ** Only rarely would makers of cheap TV sets like that produce a service manual - cos they are not economically worth servicing. Some in houses notes maybe but nothing made for sale.   Generally speaking SMD circuit boards used in consumer electronics are considered to be non serviceable.   Same applies for many other items too, in professional audio and test equipment for example.   A few keen folk make heroic efforts to reverse engineer SMD boards and effect repairs - just to spite the manufacturers.     .... Phil

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