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etpm@whidbey.com: Sep 30 08:48AM -0700 My brother's wife wants a small water heater under the kitchen sink. Not an instant hot water type but one that holds a couple gallons. There is a receptacle under the sink but it also powers the diswasher. I am concerned that if both the dishwasher and the water heater are on at the same time it will pop the breaker. I am looking for a device that will allow the water heater to be on until the diswasher starts drawing a certain amount of current, at which point the power to the heater would be turned off. The power to the dishwasher needs to be on all the time, only the heater should be switched. A switch for the water heater cannot be added. The solution needs to be plug and play and require no input from anyone using the diswasher. It seems to me that something like this must be available but I can't think of what it would be called and my brain is apparently too fuzzy this morning to get google to come up with something for me. I am willing to build the device myself if need be but a purchased product would be better. Thanks, Eric

tabbypurr@gmail.com: Sep 30 09:00AM -0700 > product would be better. > Thanks, > Eric   A relay is all you need. Remove the coil & rewind with a small number of turns of thick wire. Now when enough current goes to the dishwasher, the water heater is turned off. I'd use 2 relays the same, one to experiment, the 2nd for the final unit.     NT

"pfjw@aol.com" <peterwieck33@gmail.com>: Sep 30 09:26AM -0700 https://www.bosch-thermotechnology.us/ocsmedia/optimized/full/o416419v272_Bosch_Indirect_Tanks_(1).pdf   It is called a "Point-of-Use" water heater.   Now, some Basic Electricity 100:   The POU *STORAGE* water heater draws twelve (12) amps at rated nameplate. The typical dishwasher with an exposed internal heating element is rated at eleven (12) amps.   We keep a Bosch that does not have an exposed element but does have an on-board flash heater, and so also uses 12 A.   There are two solutions that come immediately to mind. Use a at true instant-hot for your sink water - these devices, typically, run under seven (7) amps. Then, even if you feed the dishwasher from the same line, you would be in no danger of popping a 20 A breaker - the minimum that should be in a kitchen in any case.   Or, run a second line directly to the dishwasher. Which is the way it should be done in any case.   Note that instant-hot water heaters will give you all the hand-use water you want, and nicely support a dishwasher such as it will require minimal use of its on-board heater.   Peter Wieck Melrose Park, PA

Wond <lost@the.ether.net>: Sep 30 04:27PM On Mon, 30 Sep 2019 08:48:15 -0700, etpm wrote:   > product would be better. > Thanks, > Eric   If you are in North America, and that is a "duplex" receptacle, its likeley to be an "appliance" outlet, that is, each side wired to a separate breaker. Check the labelling in the box to find out, or measure the voltage between the two "hot" connectors. 230V means you're good to go.

"pfjw@aol.com" <peterwieck33@gmail.com>: Sep 30 09:30AM -0700 > A relay is all you need. Remove the coil & rewind with a small number of turns of thick wire. Now when enough current goes to the dishwasher, the water heater is turned off. I'd use 2 relays the same, one to experiment, the 2nd for the final unit.   The good folk in Quincy, MA are recoiling in horror!   DO NOT EVEN CONSIDER this option, most especially if you have any other living things in your household.   Peter Wieck Melrose Park, PA

tabbypurr@gmail.com: Sep 29 11:02AM -0700 On Sunday, 29 September 2019 12:19:10 UTC+1, Cursitor Doom wrote: > > eventually became Motorola. They started making consumer radios, and > > then invented a record player that could be installed in an automobile.   > By God that must have taken some doing.   Cars had soft suspension & poor handling in the 50s, the ideal combination. Add a high tracking force xtal pickup and it ain't that hard. But they still skipped here & there.     NT

Bo-Lennart <bo-lennart.karlsson@telia.com>: Sep 30 01:16AM -0700 Den fredag 27 september 2019 kl. 19:48:15 UTC+2 skrev Bo-Lennart:

Bo-Lennart <bo-lennart.karlsson@telia.com>: Sep 30 01:33AM -0700 Den fredag 27 september 2019 kl. 19:48:15 UTC+2 skrev Bo-Lennart:   > Many thanks in advance   > Bo-Lennart Karlsson > Falun, SWEDEN   Thank You all for the reply. I understand that there would be easier if I could present a picture of the transfprmer. I have pics, but I don't know how to present them here in this group. I did some measuring with my L-meter, so I now know where the coils are. I'm pretty new to this group. Please tell me if I can present a picture right here in these group. Or can I present a link to eg. One Drive or DropBox or similar....   Bo-Lennart Karlsson Falun, Sweden

tabbypurr@gmail.com: Sep 30 03:19AM -0700 On Monday, 30 September 2019 09:33:35 UTC+1, Bo-Lennart wrote: > I'm pretty new to this group. Please tell me if I can present a picture right here in these group. Or can I present a link to eg. One Drive or DropBox or similar....   > Bo-Lennart Karlsson > Falun, Sweden   The newsgroup is text only. You can put pics in imgbb.com, flickr, any free pic hosting site.     NT

Cursitor Doom <curd@notformail.com>: Sep 30 03:50PM On Mon, 30 Sep 2019 01:33:31 -0700, Bo-Lennart wrote:   > I'm pretty new to this group.   Welcome aboard, friend! Unfortunately we have a few nutters here but take my advice and just ignore them. ;-)           -- 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.

tabbypurr@gmail.com: Sep 30 09:00AM -0700 On Monday, 30 September 2019 16:51:00 UTC+1, Cursitor Doom wrote:   > > I'm pretty new to this group.   > Welcome aboard, friend! Unfortunately we have a few nutters here but take > my advice and just ignore them. ;-)   Everyone needs an ignore list or killfile.

Cursitor Doom <curd@notformail.com>: Sep 29 04:43PM On Sun, 29 Sep 2019 16:01:21 +0200, Johann Klammer wrote:   > supposedly also HF(acid). arirang TV has been reporting on it..   Vile stuff.       -- 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.

danny burstein <dannyb@panix.com>: Sep 29 05:39PM >On Sun, 29 Sep 2019 16:01:21 +0200, Johann Klammer wrote:   >> supposedly also HF(acid). arirang TV has been reporting on it..   >Vile stuff.   They should have traveled to Philly:   [news story]   Toxic chemical at PES refinery mostly cleared, aiding probe of June blaze .... About 340,000 pounds of hydrofluoric acid (HF) stored at Philadelphia Energy Solutions' refinery was chemically neutralized ====== https://www.reuters.com/article/us-pes-bankruptcy-chemicals-idUSKCN1VK24U       -- _____________________________________________________ Knowledge may be power, but communications is the key dannyb@panix.com [to foil spammers, my address has been double rot-13 encoded]

Cursitor Doom <curd@notformail.com>: Sep 29 07:43PM On Sun, 29 Sep 2019 17:39:53 +0000, danny burstein wrote:   > Energy Solutions' refinery was chemically neutralized > ====== > https://www.reuters.com/article/us-pes-bankruptcy-chemicals- idUSKCN1VK24U   "HF can burn the skin"   ROTFLMFAO! :-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.

etpm@whidbey.com: Sep 29 03:30PM -0700 On Sun, 29 Sep 2019 19:43:26 -0000 (UTC), Cursitor Doom >idUSKCN1VK24U   >"HF can burn the skin"   >ROTFLMFAO! :-D Yeah, I love how some stuff is understated. Like when all those lithium batteries in laptops were catching on fire. I read a report where the burning batteries were described as "venting with flame".

Trevor Wilson <trevor@rageaudio.com.au>: Sep 30 06:12AM +1000 On 29/09/2019 9:15 pm, Cursitor Doom wrote: > make up a patch lead that will enable me to probe the board under power > out in the open where I can get at it. It's a PITA, but there's no > alternative I can see.   **It's highly likely that HP made available extension adapters to suit their test equipment back in the day. You might be able to source one. Somewhere.   -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

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amdx <nojunk@knology.net>: Sep 28 02:42PM -0500 On 9/27/2019 11:40 PM, Phil Allison wrote:   > Talks to them all the time, on long range AM radio.   > ..... Phil   Any chance I saved him from some abuse? :-) Can we call him Fred the PITA? And, I don't talk to them, I just here the voices! Mikek

Cursitor Doom <curd@notformail.com>: Sep 29 11:19AM On Sat, 28 Sep 2019 09:03:41 -0500, Dave M wrote: > Galvin Manufacturing was the original radio manufacturing company that > eventually became Motorola. They started making consumer radios, and > then invented a record player that could be installed in an automobile.   By God that must have taken some doing.       -- 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.

Phil Allison <pallison49@gmail.com>: Sep 29 07:21AM -0700 Cursitor Doom wrote:   ----------------------- > > eventually became Motorola. They started making consumer radios, and > > then invented a record player that could be installed in an automobile.   > By God that must have taken some doing.   ** I've seen a portabe 45rpm player where the disk slid into a slot like bread in a toaster. The arm was held against the vinyl surface by spring pressure.   Crystal PU, of course, with no vertical compliance - a real "groove straightener".     .... Phil

Johann Klammer <klammerj@NOSPAM.a1.net>: Sep 29 04:01PM +0200 > Japan and South Korea Feud, but Breaking Up Is Hard > New York Times - August 28, 2019 > -- https://www.nytimes.com/2019/08/28/business/japan-south-korea-trade.html   supposedly also HF(acid). arirang TV has been reporting on it..

tabbypurr@gmail.com: Sep 28 05:09PM -0700 On Saturday, 28 September 2019 00:11:38 UTC+1, Fox's Mercantile wrote:   > Yet you persist on saying carbon composition resistors are better > for a given application.   > Make up your mind.   I'm not confused. Nor am I much concerned whether you read up on them or not. Good night.

Fox's Mercantile <jdangus@att.net>: Sep 28 07:27PM -0500 >> for a given application.   >> Make up your mind.   > I'm not confused. Nor am I much concerned whether you read up on them or not. Good night.   Actually you are confused. Previously you'd said:   > Oh boy. Carbon comp is so much better at pulse work that a comp R with a given pulse rating is cheaper than a larger film type with the same pulse rating. THAT'S WHY THEY'RE USED.   Then you follow up with: > No, modern resistors used within their specs are very reliable. They're among the most reliable of electronic components. Further comment is just not worthwhile.   Yet carbon composition resistors are made the same way they've been made for the past 50 years. And with the same time and temperature drift that they've always had.   -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Jeff Urban <jurb6006@gmail.com>: Sep 28 07:26PM -0700 Whatever they all say this is the deal. First of all things that pop up when cold might be connections, if when hot they are almost always component failure.   You have to thermally cycle it several times, so go over your Grandma's place a steal an endtable. Take the case off and get a towel. Fire it up and maybe take some voltages. Cover with towel. Then when it fails take those voltages again.   Then find out where any missing voltages come from. Always remember, 70% of the time or more it only has one problem. I used to say almost all the time but that is no longer true. And things blow each other, but there is one ROOT cause of the problem.   If you can't find a case history on it you are just going to have to do it, all there is to it.   You can try Repairworld if they are still around for $11 a month. Just one month isn't going to break the bank I hope but they might not have anything on it.   Other than that, just troubleshot. Got a print ? Maybe we can look at ? I don't even know what the fuck this thing is. It could be an ICBM or a toaster fr as I know.

tabbypurr@gmail.com: Sep 29 03:31AM -0700 On Sunday, 29 September 2019 01:28:02 UTC+1, Fox's Mercantile wrote:   > Yet carbon composition resistors are made the same way they've > been made for the past 50 years. And with the same time and > temperature drift that they've always had.   which part of > I'm not confused. Nor am I much concerned whether you read up on them or not. Good night. did you not grasp? I don't need an answer.

Cursitor Doom <curd@notformail.com>: Sep 29 11:15AM On Sat, 28 Sep 2019 19:26:22 -0700, Jeff Urban wrote:   > Other than that, just troubleshot. Got a print ? Maybe we can look at ? > I don't even know what the fuck this thing is. It could be an ICBM or a > toaster fr as I know.   It's an old HP 8565A RF spectrum analyser built with good old fashioned discrete components you can physically see. The problem I'm having is access. I have identified the failed board: the x-amplifier module. They've used plug-in boards which is great in one way, except that they're so closely juxtaposed with other plug-in boards it's impossible to carry out any traditional troubleshooting techniques whilst under power. Believe me, I've tried. Tacking on fine wires to various key connections and running them out for probing and whatnot but I'd end up with a right old rat's nest of a mess if I carry on like that much longer. I've discovered a lot of old tower computers use the same pitch of plug in board that HP used (3.96mm) so I've ordered a matching socket and will make up a patch lead that will enable me to probe the board under power out in the open where I can get at it. It's a PITA, but there's no alternative I can see.     -- 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.

Larz <dispcal667@nospam.net>: Sep 28 05:36PM -0400 Ok, so I picked up a Kuman Electricity Usage Monitor. For anyone not familiar, it shows KW used, current V and I, some other things like a cost calculation, etc. I plugged the 175 W mercury lamp into it and here are the figures I got after letting the system run for 8 hours, 35 min:   1.77 Kwh 209.8 W 0.19 cost 2.018 A 0.84 pfc   So, inputting my Kwh rate beforehand, it's showing ~19 cents per 8 hour period.   I have no idea if these figures are correct and probably won't until the electric bill arrives and/or I ever came across a scope. The device had good ratings and most folks seemed satisfied, which was the main reason I purchased it.

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Bo-Lennart <bo-lennart.karlsson@telia.com>: Sep 27 10:48AM -0700 Hi all out there. I found a transformer in my basement. I don't know if its a audio-output transformer or just a power transformer. On top it's stamped "GALVIN MANUFACTURING CORPORATION", and a model #: "25B31296-E" and a serial# ( ???? ) "138226" At bottom there is 8 solder lugs, stamped: "1 to 8". And at one side is 8 screw connector, labeled as "3A 12 11 2B 2A 10 1A 9".   To me it looks more like a tube output transformator, more than a power transformer. It seems to be from the 1940 or somewhere around there.   Anyone know what it is, and have some kind of "schematic" of the transformer.   Many thanks in advance   Bo-Lennart Karlsson Falun, SWEDEN

Bo-Lennart <bo-lennart.karlsson@telia.com>: Sep 27 11:39AM -0700 Den fredag 27 september 2019 kl. 19:48:15 UTC+2 skrev Bo-Lennart:

"pfjw@aol.com" <peterwieck33@gmail.com>: Sep 27 11:54AM -0700 On Friday, September 27, 2019 at 1:48:15 PM UTC-4, Bo-Lennart wrote:   > Many thanks in advance   > Bo-Lennart Karlsson > Falun, SWEDEN   Galvin Manufacturing is the company that produced Motorola products out of Chicago, Illinois, USA. It is easy enough to trace it out using a small AC power-supply and a good True RMS VOM.   https://www.radioremembered.org/xfmr.htm takes you to the RMA (Radio Manufacturers' Association) Transformer color-code for power transformers. Motorola, being a founding member of the RMA would typically follow these codes, but for their military stuff that followed a different code, sometimes.   Audio Output Transformers usually have Green-Black-Green (and mixes) on the secondary side, and Blue-Red-Blue (and mixes) on the primary side.   Note that transformers often have multiple taps on the same winding. So: a) Using your Ohms setting isolate the various windings from each other. A single winding will show continuity, but with variations in resistance from one tap to the next. b) Isolate the windings from the lowest total resistance to the most total resistance - this is trickier than it seems as you want to include all taps, but measure the complete winding, not an internal tap. Even more so, if, for instance, you have a 5V winding off a 120 V primary - it will have a lower resistance than the primary winding - more on this later. Bundle each winding and all the taps together so as not to mix them up. c) Starting with the lowest-resistance winding, apply some reasonable, but low, AC voltage -say about 20 VAC or so. d) Measure voltages on the other windings. By experimentation, you should be able to discern the purpose of the transformer, the primary winding and any taps, and the secondary windings as well.   As an example: A typical audio power for tube equipment here in the US would get 120 VAC on the primary side, have a B+ winding that might give something between 325 and 450 VAC, one or two 6.3 V filament windings and, perhaps a 5 V filament winding. That would be as many as five total windings. Some few even have dual primary windings to accommodate multiple input voltages. So, it is complicated.   An audio transformer may have multiple taps, but the turns ratio between the primary and the full secondary will be fixed, and there will be only two windings in total.   Take your time - it is almost entirely unlikely that you will be able to trace *that* transformer by its part number.   Hope that helps.   Peter Wieck Melrose Park, PA

Fred Smith <fredsmith@thejanitor.corp>: Sep 27 10:21PM > Many thanks in advance   > Bo-Lennart Karlsson > Falun, SWEDEN   Audio output transformers generally don't interleave the "E" and "I" laminations, and may have an obvious bit of waxy paper between the block of E and I laminations. Power transformers almost invariably do interleave the laminations (I've never seen one that didn't).

Phil Allison <pallison49@gmail.com>: Sep 27 06:10PM -0700 Fred Smith wrote:   ----------------------   > Audio output transformers generally don't interleave the "E" and > "I" laminations, and may have an obvious bit of waxy paper between > the block of E and I laminations.   ** Small transformers intended for "single ended" operation are like that - the rest are like power transformers.   The OP is being a real PITA by NOT supplying any info on how big his unit is or any of the winding resistances.   A pic would be revealing too.       .... Phil

amdx <nojunk@knology.net>: Sep 27 08:18PM -0500 On 9/27/2019 5:21 PM, Fred Smith wrote: > the block of E and I laminations. Power transformers almost > invariably do interleave the laminations (I've never seen one that > didn't).   Well Fred, if you are correct in your assertions, you will be Fred, if Phil gives us his wisdom and it doesn't agree, we will find your aliases. Mikek

Phil Allison <pallison49@gmail.com>: Sep 27 09:40PM -0700 amdx wrote:   ------------     > Well Fred, if you are correct in your assertions, you will be Fred, if > Phil gives us his wisdom and it doesn't agree, we will find your aliases. > Mikek   ---------------------------   FYI to all:   The Mikek troll knows more about "Aliens" than aliases.   Talks to them all the time, on long range AM radio.       ..... Phil

Michael Terrell <terrell.michael.a@gmail.com>: Sep 28 05:43AM -0700 On Friday, September 27, 2019 at 1:48:15 PM UTC-4, Bo-Lennart wrote: > It seems to be from the 1940 or somewhere around there.   > Anyone know what it is, and have some kind of "schematic" of the transformer.   > Many thanks in advance     25B31296-E is typical of Motorola part numbering.   It crosses to a NSN part which is a 120VAC 60Hz input power transformer:   https://nationalstocknumber.org/nsn/5950-00-648-0400   NSN are inventory numbers for items bought by the government.

"Dave M" <dgminala@mediacombb.net>: Sep 28 09:03AM -0500 Bo-Lennart wrote:   > Many thanks in advance   > Bo-Lennart Karlsson > Falun, SWEDEN   Galvin Manufacturing was the original radio manufacturing company that eventually became Motorola. They started making consumer radios, and then invented a record player that could be installed in an automobile. Thus, came the name MOTOROLA, from MOTOR cars, and the old victROLA record player (from RCA). The 25B31296 part number identifies as a Motorola transformer, having the following characteristics from the US military stock system:   5950-00-648-0404 Features MRC Parameter Characteristics ABKQ Center to Center Distance Between Mounting Facilities Parallel to Length 2.625 inches nominal single mounting facility single center group ABKR Center to Center Distance Between Mounting Facilities Parallel to Width 2.375 inches nominal single mounting facility single center group ABTB Mounting Hole Diameter 0.125 inches nominal single group ACZB Frequency Rating 60.0 hertz nominal single component ACZC Input-Output Phase Relationship Three phase to three phase single component ADAQ Body Length 3.875 inches nominal ADAT Body Width 3.875 inches nominal ADAU Body Height 3.500 inches nominal AKNA Inclosure Type Hermetically sealed AKPV Mounting Facility Quantity 4 single group AXGY Mounting Method Flange single group and unthreaded hole single group BPLC Winding Function and Quantity 1 primary single component and 2 secondary single component CWJS Winding Operating Voltage 145.00 ac volts nominal single component 1ST secondary CWJS Winding Operating Voltage 12.00 ac volts nominal single component single primary CWJS Winding Operating Voltage 5.80 ac volts nominal single component 2ND secondary TTQY Terminal Type and Quantity 8 threaded stud and 7 tab, solder lug     No indication of the equipment it was used in, but more than likely a piece of military equipment. Since the primary is specified as 12VAC, and secondaries as 145V and 5.8V, it is likely to be a power transformer from a vibrator power supply used in a military radio of some sort. Don't know how the 3-phase spec works into it... could just be how the vibrator side of the transformer was described.   Cheers, Dave M

legg <legg@nospam.magma.ca>: Sep 27 04:58PM -0400 On Fri, 27 Sep 2019 06:55:28 -0700 (PDT), John-Del <ohger1s@gmail.com> wrote:     >On plug in, the power supply standby supply turns on which feeds the standby voltage to the main board. The main board starts loading its software - this usually takes about 5 seconds on newer TVs. When the software is loaded, the main board then turns on the "run" supply of the power supply. The power supply turns on and feeds the run supply (typically about 12V) back to the main. The main detects the run voltage, shuts off the power supply and goes into standby to wait for a remote signal or the power contact to be pushed.   >So if you see the "ps-on" line high and no 12V (just the standby 3.3V or 5V), the power supply is the problem, not the main. If the power supply ps-on line never goes high at any point, the main is bad or being locked up by a peripheral board.   >It seems that there are two versions of that model; one has a separate power supply and main, and the other has them on one board. So if yours is a really low end toilet, the power supply is combined with the main board, so identifying control lines is a real problem. If you have an all in one it's best to troll the internet and look for a donor.   This had one main board with power and secondary-side signal processing/communications/audio etc, with a smaller board interfacing the led strings.   The PFC section (400v boost) was enabled, with four secondary-side supplies ID'd as running (12v, 5v, 3v3, and 1v2).   UD3, marked GH6K, seemed to be the non-functioning postregulator - I assume it would supply something between 5v and 1v2, considering the lack of designer discipline in the selection of chipsb but couldn't be sure it wasn't disabled internally.   As I've said, there's no sign of parts on offer for this thing, or a manual.   RL   After a long power withdrawal, the unit could be convinced to give a single lamp burst after start-up, but this was not evident in response to soft on/off cycles. I assume that's latching protection of some sort.

John-Del <ohger1s@gmail.com>: Sep 28 02:30AM -0700 On Friday, September 27, 2019 at 4:54:50 PM UTC-4, legg wrote:   > single lamp burst after start-up, but this was not evident in response > to soft on/off cycles. I assume that's latching protection of some > sort.   Referring back to the boot/start strategy I mentioned, a very few models will also enable the backlight on briefly before the main IC decides everything is fine and go to standby mode. You may have an LED issue in the screen..   LEDs issues can be challenging. Some really cheap models use a single string of LEDs in series. Any open LED or an LED that is dropping more than it's nominal voltage (either 3V or 6V LED) will trigger either an over-voltage or under-current condition that will cause the LED driver IC to output an "alarm" to the main IC.   If you're lucky, there will be two or more channels of LED strings and hopefully they'll all contain the same amount of LEDs in each channel. If so, you can use an external tester like this one:   https://www.ebay.com/itm/New-330V-TV-LED-Backlight-Constant-Current-Board-Tester-Tool-Repair-TV-Led-Strip/392260386303?hash=item5b548a7dff:g:e-8AAOSwRFNcjO5H   Some TVs (many LGs) use a two channels system but run an odd number of LED strips for each, so comparing one channel to the other won't be of any help. One channel strings also leave no reliable reference to test against. Sometimes you just have to pull the screen and do an exploratory.   I would guess that your RCA is a two channel system using balanced strings. Disconnect the LED harness and use the LED tool to check the running voltage of both strings. If one string is open, you found your problem. If one string measures a few volts different from the other, that could also be your problem.   If you intend to work on TVs, you MUST have and LED tester. You can buy LEDs from Alibaba. I keep three types: 3V square, 6V square, and 6V "puzzle piece". You can also buy the complete strips and not have to deal with changing the individual LEDs, but this cuts into profit immensely.

legg <legg@nospam.magma.ca>: Sep 28 09:52AM -0400 On Sat, 28 Sep 2019 02:30:06 -0700 (PDT), John-Del <ohger1s@gmail.com> wrote:     >Some TVs (many LGs) use a two channels system but run an odd number of LED strips for each, so comparing one channel to the other won't be of any help. One channel strings also leave no reliable reference to test against. Sometimes you just have to pull the screen and do an exploratory.   >I would guess that your RCA is a two channel system using balanced strings. Disconnect the LED harness and use the LED tool to check the running voltage of both strings. If one string is open, you found your problem. If one string measures a few volts different from the other, that could also be your problem.   >If you intend to work on TVs, you MUST have and LED tester. You can buy LEDs from Alibaba. I keep three types: 3V square, 6V square, and 6V "puzzle piece". You can also buy the complete strips and not have to deal with changing the individual LEDs, but this cuts into profit immensely.   I'm aware of LED issues - this one didn't seem to have an identifiable power port for separate strings. The flash showed no open strings or dull areas as viewded from the rear vents - hence my suspicion re LV post regs.   The flash isn't repeated for controlled on/off sequences; only after long delayed line power applications, so this is some kind of latching hard fault.   The unit's not here any more - was in for free inspection/quote and I had to admit that it was beyond current capabilities for competent repair - no docs or spares.   Usually I can offer options, doc costs, or physical kluges to get the thing up and running etc. There are sets out there now with 3/4 strings and slightly darker areas on the edges of the screen - simply cheaper than relamping - gives owner time to consider replacement or relamping as an option, without loosing their 'TV time', in the meanwhile. For relamping, I refer them to guys who do it (and not much else) all the time.   I haven't had a TV in my own home for decades, though the computers are threatening to become/contain the same kind of rubbish.   RL

Jon Elson <elson@pico-systems.com>: Sep 27 02:15PM -0500 On Fri, 27 Sep 2019 05:16:40 -0700, mogulah wrote:     > Japan and South Korea Feud, but Breaking Up Is Hard New York Times - > August 28, 2019 -- > https://www.nytimes.com/2019/08/28/business/japan-south-korea-trade.html   Wow, they know how to hit them where it hurts! Photoresist! Yikes!   Jon

bruce2bowser@gmail.com: Sep 27 04:01PM -0700 On Friday, September 27, 2019 at 3:15:37 PM UTC-4, Jon Elson wrote: > > August 28, 2019 -- > > https://www.nytimes.com/2019/08/28/business/japan-south-korea-trade.html   > Wow, they know how to hit them where it hurts! Photoresist! Yikes!   You gotta wonder how Japan got such a corner on that stuff. A lot like China has a lock on the rare-earths, I guess.

Ralph Mowery <rmowery28146@earthlink.net>: Sep 27 07:31PM -0400 In article <00288d06-e925-4900-bebb-be87a59fa012@googlegroups.com>, bruce2bowser@gmail.com says...   > You gotta wonder how Japan got such a corner on that stuff. A lot like China has a lock on the rare-earths, I guess.   Was that Japan or another country that had some special epoxie (whatever) that was the covering for IC memory chips way back in the 1 K per chip days ?

Clifford Heath <no.spam@please.net>: Sep 28 06:17PM +1000 >>> https://www.nytimes.com/2019/08/28/business/japan-south-korea-trade.html   >> Wow, they know how to hit them where it hurts! Photoresist! Yikes!   > You gotta wonder how Japan got such a corner on that stuff. A lot like China has a lock on the rare-earths, I guess.   China doesn't have a lock on rare earths. The ores are available in many countries, including Australia. What China does more than anyone else does is *process* the ore, because the processes are incredibly polluting and they don't care about pissing in their own pool. If they ever tried to really restrict trade in rare earths you'd find plenty of countries ramping up their processing programs.   Clifford Heath

xushenghui2015@gmail.com: Sep 27 09:25PM -0700 Did you ever get a schematic because I need one for mine too. Can you send me one via email pdf sanfy@netease.com

tabbypurr@gmail.com: Sep 27 09:49AM -0700 On Friday, 27 September 2019 11:43:04 UTC+1, Fox's Mercantile wrote:   > Which is the worst possible way of using a carbon composition > type of resistor.   > Peter told you that. I told you that.   it's the worst way to use any resistor, but that is immaterial. When an EE needs a resistor with large pulse tolerance, carbon comp is the best candidate for the job, and by a long way. There's no other reason to use them nowadays, no other way in which they're better, and they certainly aren't cheaper.   Are you really claiming to not know this stuff?     NT

tabbypurr@gmail.com: Sep 27 09:51AM -0700 On Friday, 27 September 2019 12:38:39 UTC+1, Fox's Mercantile wrote:   > > Arie   > Obviously, you're using the film types incorrectly and not specifying > specifying the correct rating for the application.   Oh boy. Carbon comp is so much better at pulse work that a comp R with a given pulse rating is cheaper than a larger film type with the same pulse rating. THAT'S WHY THEY'RE USED.     NT

"pfjw@aol.com" <peterwieck33@gmail.com>: Sep 27 11:23AM -0700 Operative word being "CHEAPER".   Which is what I am getting to with the comment "kicking the can down the road".   Being that this is a hobby for me, there are very few things that I purchase in sufficient quantities that even a 100% premium (and it is nowhere near that for resistors) is not worth the extra cost for the avoidance of trouble. I just purchased a lot of electrolytic capacitors to go into tube equipment - the premium for 105 C High-Hours caps vs. standard caps came to about 5% across 20 caps in total.   Peter Wieck Melrose Park, PA

Fox's Mercantile <jdangus@att.net>: Sep 27 01:24PM -0500 >> specifying the correct rating for the application.   > Oh boy. Carbon comp is so much better at pulse work that a comp R with a given pulse rating is cheaper than a larger film type with the same pulse rating. THAT'S WHY THEY'RE USED.   > NT   Oh, that's right. I forgot you're never wrong.   Even when you are.     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

tabbypurr@gmail.com: Sep 27 03:41PM -0700 > Operative word being "CHEAPER".   > Which is what I am getting to with the comment "kicking the can down the road".   No, modern resistors used within their specs are very reliable. They're among the most reliable of electronic components. Further comment is just not worthwhile.     NT

Fox's Mercantile <jdangus@att.net>: Sep 27 06:11PM -0500 >> Which is what I am getting to with the comment "kicking the can down the road".   > No, modern resistors used within their specs are very reliable. They're among the most reliable of electronic components. Further comment is just not worthwhile.   > NT   Yet you persist on saying carbon composition resistors are better for a given application.   Make up your mind.       -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

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legg <legg@nospam.magma.ca>: Sep 27 08:47AM -0400 Somebody brought in an RCA RLDED5098-D-UHD widescreen TV the other day.   Damned if I could find service info or any spares on offer.   Though it looked like a small post-regulator wasn't running, to prevent operation, there was no way to find out if it was supposed to be off during a protective fault, or what the replacement parts were, from smd coding alone.   It looked like the only alternative to the owner, for repair, was a box distributor in the sticks of the greater Toronto area. This would be complicated by a apparent lack of a serial number on the thing.   This is the first time I've run into this situation. From a service manual information, I can generally do something.   RL

John-Del <ohger1s@gmail.com>: Sep 27 06:55AM -0700 On Friday, September 27, 2019 at 8:44:05 AM UTC-4, legg wrote:   > This is the first time I've run into this situation. From a service > manual information, I can generally do something.   > RL   You won't get any help from "RCA"..   Try disconnecting the TCON, the LED harness, and any remote and wifi boards and see if it responds differently.   Many of these use a particular start (ping-pong) sequence:   On plug in, the power supply standby supply turns on which feeds the standby voltage to the main board. The main board starts loading its software - this usually takes about 5 seconds on newer TVs. When the software is loaded, the main board then turns on the "run" supply of the power supply. The power supply turns on and feeds the run supply (typically about 12V) back to the main. The main detects the run voltage, shuts off the power supply and goes into standby to wait for a remote signal or the power contact to be pushed.   So if you see the "ps-on" line high and no 12V (just the standby 3.3V or 5V), the power supply is the problem, not the main. If the power supply ps-on line never goes high at any point, the main is bad or being locked up by a peripheral board.   It seems that there are two versions of that model; one has a separate power supply and main, and the other has them on one board. So if yours is a really low end toilet, the power supply is combined with the main board, so identifying control lines is a real problem. If you have an all in one it's best to troll the internet and look for a donor.

mogulah@hotmail.com: Sep 27 05:16AM -0700 "One of those chemicals, known as photoresist, is critical for top-of-the-line products produced by Samsung Electronics, the giant South Korean maker of chips and gadgets, among others. Japan controls around 90 percent of the world's supply."   Japan and South Korea Feud, but Breaking Up Is Hard New York Times - August 28, 2019 -- https://www.nytimes.com/2019/08/28/business/japan-south-korea-trade.html

tabbypurr@gmail.com: Sep 26 01:17PM -0700 > > We use carbon film aplenty. The reasons are low cost & good availability. > > Carbon comp is used on occasion for its pulse power tolerance.   > In other words, kick the can down the road....   it's not clear what issue you're referring to there.     NT

"pfjw@aol.com" <peterwieck33@gmail.com>: Sep 26 01:45PM -0700 The fact that carbon resistors have a pretty wretched service life and heat tolerance.   Peter Wieck Melrose Park, PA

Trevor Wilson <trevor@rageaudio.com.au>: Sep 27 07:24AM +1000 On 22/09/2019 8:46 pm, Cursitor Doom wrote: > is/are the most likely suspects to be considered blameworthy? I'm > guessing dry joints has to be on the list somewhere, but what components > can also give rise to this issue?   **All of them, but semiconductors are the most likely culprits. The worst I've seen was a varistor used in the Marantz 2325 receiver from the 1970s. When cold, the varistor was fine. As it warmed up, the amp shut down, due to huge DC shifts. As it warmed further, the amp returned to normal operation. I found that the critical temperature range was fairly narrow. Around 5 degrees C, at around 35 degrees C. It was a bugger to fault find, because the usual freezer spray would transition the component from hot to cold too quickly for the fault to appear.   -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

tabbypurr@gmail.com: Sep 26 02:44PM -0700 > The fact that carbon resistors have a pretty wretched service life and heat tolerance.   > Peter Wieck > Melrose Park, PA   you're clearly misinformed

Fox's Mercantile <jdangus@att.net>: Sep 26 05:42PM -0500 >> Peter Wieck >> Melrose Park, PA   > you're clearly misinformed   30 years of servicing vintage radios tells me you're the one misinformed.   -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

tabbypurr@gmail.com: Sep 27 02:08AM -0700 On Thursday, 26 September 2019 23:42:18 UTC+1, Fox's Mercantile wrote:   > > you're clearly misinformed   > 30 years of servicing vintage radios tells me you're the one > misinformed.   Vintage is the key word there. Ancient carbon composition are indeed prone to rising in value & going oc. However carbon film Rs have an excellent reliability record. I've repaired lots of stuff over however many years, and carbon film Rs are almost never a problem.   I've no doubt your ego will not permit you to get real, so I see little point continuing this. Others who read this will make up their own minds.     NT

Fox's Mercantile <jdangus@att.net>: Sep 27 05:42AM -0500 > I see little point continuing this. Others who read this > will make up their own minds.   > NT   Do you even pay attention to what you write?   "Carbon comp is used on occasion for its pulse power tolerance."   Which is the worst possible way of using a carbon composition type of resistor.   Peter told you that. I told you that.   -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Arie de Muynck <no.spam@no.spam.org>: Sep 27 01:25PM +0200 On 2019-09-27 12:42, Fox's Mercantile wrote: > "Carbon comp is used on occasion for its pulse power tolerance."   > Which is the worst possible way of using a carbon composition > type of resistor.   Why is that? This is IMHO not about the carbon film type but about modern massive carbon composition. I've used them for > 40 years in e.g. triac snubber networks and they never failed. All kinds of (same wattage rating) film types did fail. Wirewound is also OK but too expensive.   Arie

Fox's Mercantile <jdangus@att.net>: Sep 27 06:38AM -0500 On 9/27/19 6:25 AM, Arie de Muynck wrote: > triac snubber networks and they never failed. All kinds of (same wattage > rating) film types did fail. Wirewound is also OK but too expensive.   > Arie   Obviously, you're using the film types incorrectly and not specifying specifying the correct rating for the application.     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

"pfjw@aol.com" <peterwieck33@gmail.com>: Sep 27 04:39AM -0700 http://carlscustomamps.com/do-carbon-composition-and-carbon-film-resistors-sound-better   https://www.aikenamps.com/index.php/resistor-types-does-it-matter   And so on.   What it comes down to is cost. And, in my experience, those who wish to believe that cost is not the issue will throw up all sorts of smoke and mirrors around audiophoolery.   Peter Wieck Melrose Park, PA

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tabbypurr@gmail.com: Sep 25 03:13PM -0700 > As already noted, many things *can* get hot. What is in question is how heat will affect various components. In no particular order:   > a) Carbon comp/film resistors will change value over time, and much more-so of heated. Some types are so awful that they will change in value simply from the heat required to install them. Given the alternatives, the only reason to use them today would be based on audiophoolery.   We use carbon film aplenty. The reasons are low cost & good availability. Carbon comp is used on occasion for its pulse power tolerance.     NT

"pfjw@aol.com" <peterwieck33@gmail.com>: Sep 26 03:56AM -0700 > We use carbon film aplenty. The reasons are low cost & good availability. > Carbon comp is used on occasion for its pulse power tolerance.   In other words, kick the can down the road....   Peter Wieck Melrose Park, PA

Phil Allison <pallison49@gmail.com>: Sep 25 05:52PM -0700 John-Del wrote: -------------- Phil Allison wrote:   > I can promise you that if you saw several of these a month, > you would have by now acquired both the equipment (cheap enough) > and the skill to do this in your sleep.   ** The bigger issue with SMD boards is that makers do not expect them to be repaired so discourage service techs from even attempting.   To this end, they make NO service info available, provide NO schematics and sell NO spare parts that go on such boards.   Invariably, the PCBs are double sided with vias, making visual circuit tracing a nightmare and hence fault diagnosis too.   By sheer dint of effort I have fixed a number of items that used SMD, sometimes using regular parts to relace SMD versions.   One ( famous Italian make ) powered speaker PCB was possessed with heat sensitive intermittents that another good tech could not fix. I found a faulty via and fixed that - then found about 20 others after applying heat to them individually using a soldering iron tip. Some of the vias were solder filled, so not so easy to run a wire through.   BTW:   My eyesight is Ok and I have a magnifying glass - I still fix broken, hair fine wires on Accutronics reverb unit coils ( ones with plugs and sockets) rather then replace the whole tank.   Investing in SMS gear and a stock of parts would NOT be sensible or economic.     ..... Phil

Ralph Mowery <rmowery28146@earthlink.net>: Sep 25 12:47PM -0400 In article <16a879a4-381c-4f70-a7c6-12b2ef95c5cd@googlegroups.com>, pallison49@gmail.com says...   > It has everything to do with the current wave be made up of pulses ( at double the supply frequency ) and so not being a sine wave.   > The "true rms" value of a pulsed current is higher than a comparable steady sine current.   Ok I can see that , The meters are not really showing what is going on. I do understand the part about a 'true rms' not being the same as what most simple meters show when calibrated for a sine wave and not all kinds of non sine waves.   Just faulty thinking about the inductance of a transformer.

Phil Allison <pallison49@gmail.com>: Sep 25 04:51PM -0700 Ralph Mowery wrote:   ------------------- > most simple meters show when calibrated for a sine wave and not all > kinds of non sine waves.   > Just faulty thinking about the inductance of a transformer.   ** The simple mistake that most folk make is not knowing the definition of VA and hence the meaning of Power Factor.   FYI: VA = rms Voltage times rms Current.   and PF = true power / VA   For example,   a true rms clamp mater allows a sparkie to measure the VA of a load but he would need a "watt-meter" to find the true power.   Plug-in meters that do both cost very little nowadays.     .... Phil

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