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andrew@cucumber.demon.co.uk (Andrew Gabriel): Feb 27 11:20AM In article <sNGdnTReYdJz31fLnZ2dnUU7-I-dnZ2d@westnet.com.au>,   > I'll believe Aluminium or steel I must admit to only a little actual > experience. > Some Cable guy should give an actual answer.   Ordinary soldering can be used with iron - soldering iron bits are often copper core for thermal capacity and conduction, with iron plating which wets well with solder but doesn't oxidise/corrode as quickly as a bare copper bit does.   As you go to steel and then stainless steal, it gets harder to do. Stainless steal in particular is protected from corrosion by a very tough layer of chromium oxide (I don't know if it's possible to solder stainless steel at all).   Aluminium has a similar problem - a very tough layer of aluminum oxide which needs a suitable flux to strip through. However, it also needs a different solder alloy to wet it - it's a long time since I did it but ISTR using a solder alloy containing silver.   A secondary problem with soldering dissimilar metals is that any moisture risks causing galvantic action/corrosion of the join, and in the case of aluminium, this happens even between the aluminium and the solder used. Selecting a flux which can strip the aluminimum oxide well whilst not leaving any residue which eventually corrodes the join is a bit of a challenge.   -- Andrew Gabriel [email address is not usable -- followup in the newsgroup]

DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org>: Feb 27 01:10PM On Sat, 27 Feb 2016 11:20:43 +0000, Andrew Gabriel wrote:   > As you go to steel and then stainless steal   Engineering schlip?

MJC <gravity@mjcoon.plus.com>: Feb 27 04:28PM In article <nas0qb$nod$1@dont-email.me>, andrew@cucumber.demon.co.uk says... > and the solder used. Selecting a flux which can strip the aluminimum > oxide well whilst not leaving any residue which eventually corrodes > the join is a bit of a challenge.   This reminded me that I once knew about "purple plague". There's an article about it in Wikipedia.   Mike.

Aleksandr Motsjonov <soswow@gmail.com>: Feb 26 09:59PM -0800 John-Del, I've looked a bit more. I found labels on back side. One of the inputs from FRC Board is "ON_BACK", and there is also "P_ON" both are zero V when turned off, and when I press power the both get up to 3.2V "EN" and "ADJ" that goes to power supply board are at GND level at all times. The backlight voltage shows 25.8 when turned off, and 32.3 when turned on. I don't have a oscilloscope to see what kinda of shape this signal is. I still don't understand how does power supply "decides" when to change backlight voltage if "EN" and "ADJ" don't seems to be changing at all ... or maybe I measuring wrong.

John-Del <ohger1s@aol.com>: Feb 27 03:59AM -0800 On Saturday, February 27, 2016 at 12:59:31 AM UTC-5, Aleksandr Motsjonov wrote: > "EN" and "ADJ" that goes to power supply board are at GND level at all times. > The backlight voltage shows 25.8 when turned off, and 32.3 when turned on. I don't have a oscilloscope to see what kinda of shape this signal is. > I still don't understand how does power supply "decides" when to change backlight voltage if "EN" and "ADJ" don't seems to be changing at all ... or maybe I measuring wrong.   First you need to determine if you have a floating ground on the LED strips. You can do a resistance check from the ground plane of the power supply or metal frame of TV to either side of the LED connector. If one side reads zero ohms, use the frame or ground screw for your LED voltage. If not, locate a large electrolytic near the LED output section. This will have a voltage rating of 100 to 450 volts and the neg side of the cap will make a good ground. There are several ways the LED voltage is varied on these. Sometimes they actually vary the DC output, other times they use a mosfet on the low side of the LED strips and modulate the gate to provide the proper voltage drop across the string. Your reading is odd. It clearly is changing voltage but there doesn't seem to be enough difference between off and on to go from LED cutoff to full bright, but I could be wrong on this.   To answer your other questions takes some more guessing (again, no SM). In standby, the SMPS will put out either 3.3 or 5v typically for the main. The P_ON command from the main turns on the other outputs of the SMPS, such as 9, 12, 24 as required for the rest of the circuitry. In some TVs, this also turns on the PFC circuit (if equipped). When the PFC turns on, you'll see a big bump of voltage on this cap. Other boards will use a command from the inverter drive IC to turn on the PFC (rare). Still others use the successful power up of one of the other secondary supplies to turn on the PFC.   Not all configurations use the adj and enable lines, particularly the real cheap TVS. Is your "EN" line also the "ON_BACK" line? You can try floating the adj line to see if the backlight voltage increases.   Most times if a TV's status LED reports a start when the button is pushed and successfully turns on the power supply, the main is OK (but not always :(. I've seen some Vizios that will turn on everything but the backlight because the PWM (brightness) is missing.   The secret to all of this is datasheets. If you can find the datasheets for the LED drive IC (and PFC if it's equipped with one) you can go a long way with the proper pin outs, typical voltages, sample circuits, and descriptions of signals the ICs use.

John-Del <ohger1s@aol.com>: Feb 27 04:05AM -0800 On Sunday, February 21, 2016 at 4:32:57 PM UTC-5, Aleksandr Motsjonov wrote: > OK. I see what you mean. But I have problem understand how does PFC or any other logic board would be able to control LED. > The only connection power board has with main board via these 6 pin connection. > The only interesting bits here are ON/OFF and ADJ. Not sure if any of these would control output of the LEDs power output on other side of the power board:   I see an 8 pin connector on the close up that has two commands. If that is the only connector then the LED section is turned on with the rest of the power supply. The adjust will adjust the brightness of it. Because the main and smps/inv seem to be made by two different companies, they label them differently but I believe the enable and on/off turn on both the power supply and LED drive. If both of those go high, odds are very high that you have a problem either in the smps or an open LED.

Aleksandr Motsjonov <soswow@gmail.com>: Feb 27 04:11AM -0800 Thank you mate. Will read it carefully and do my best! Here is couple more photos with overall picture, back of this central boards set (With connector from FRC pin out) https://goo.gl/photos/FHLZtEyEj3QCFGMu5

Julian Barnes <jb9889@notformail.com>: Feb 26 07:08PM hey guys,   I need to remove a sub-miniature audio transformer from a PCB. It should be a piece of cake and always has been in the past, but something's different about this one. At those odd times previously when I've done this, I've just used a soldering iron and a vacuum pump to melt the joints and suck off the solder. The pins are then free and the part almost drops off by itself. This one is not so simple, though. It's a double-layer board and the transformer is mounted directly on top of the traces that feed it. On the reverse side, I can see the end of the transformer's leads poking through just proud of where a pad would normally be, but in this case, there are no pads 'cos there are no traces; just tiny, isolated circles of solder around each lead-end. I guess I need to get at the actual solder joints proper on the top side, but the transformer is sat right on top of them making it totally impossible to even see the joints I need to get at! Whut gives here? Are these things deliberately designed to be unserviceable nowadays? Is that the idea? Bastard manufacturers want us to buy new stuff instead of fixing old? Sigh. Does anyone know a ruse to defeat this darstardly scam?

"tom" <tmiller11147@verizon.net>: Feb 26 02:29PM -0500 "Julian Barnes" <jb9889@notformail.com> wrote in message news:naq7rg$3c4$1@dont-email.me... > nowadays? Is that the idea? Bastard manufacturers want us to buy new > stuff instead of fixing old? > Sigh. Does anyone know a ruse to defeat this darstardly scam?   Hot air desoldering tool.   This one works nice:   http://www.ebay.com/itm/281501377815?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT   Consider adding ChipQuick to lower the melting point.   http://www.ebay.com/itm/CyberDoc-CHIP-Quik-Quick-DESOLDERING-REMOVAL-ALLOY-2ft-FOUR-4x-6-5-inch-STICKS-/141758972378?hash=item21017e41da:g:XGcAAOSwPgxVLEkM   And flux.

N_Cook <diverse@tcp.co.uk>: Feb 26 07:28PM On 26/02/2016 19:08, Julian Barnes wrote: > nowadays? Is that the idea? Bastard manufacturers want us to buy new > stuff instead of fixing old? > Sigh. Does anyone know a ruse to defeat this darstardly scam?   Diamond encrusted cutting wire?

Cursitor Doom <curd@notformail.com>: Feb 26 10:00PM On Fri, 26 Feb 2016 19:08:33 +0000, Julian Barnes wrote:   > Are these things deliberately designed > to be unserviceable nowadays?   Probably.     > Is that the idea? Bastard manufacturers > want us to buy new stuff instead of fixing old?   Surely.   > Sigh. Does anyone know a ruse to defeat this darstardly scam?   They're a PITA - IME at any rate. This is one of the better explanations on how to deal with them:   https://www.youtube.com/watch?v=Z38WsZFmq8E

Rheilly Phoull <rheilly@bigslong.com>: Feb 27 07:23AM +0800 On 27/02/2016 6:00 AM, Cursitor Doom wrote:   > They're a PITA - IME at any rate. This is one of the better explanations > on how to deal with them:   > https://www.youtube.com/watch?v=Z38WsZFmq8E   The power suction jobs take some beating :-)

N_Cook <diverse@tcp.co.uk>: Feb 27 09:43AM On 26/02/2016 19:28, N_Cook wrote: >> stuff instead of fixing old? >> Sigh. Does anyone know a ruse to defeat this darstardly scam?   > Diamond encrusted cutting wire?   If soldered rather than rf welded joints. A small length of tungsten wire from a smashed 40W mains lamp, crimped to thicker delivery wire. Varying current of a bench ps, find the current for dull red heat of the tungsten. Drape the tungsten wire over one of the pins , and a forcing blade/wedge in the gap while delivering heat to that pin and repeat?

N_Cook <diverse@tcp.co.uk>: Feb 26 04:46PM On 26/02/2016 16:16, Mike Tomlinson wrote: >> First with a soldering iron barrel , confirm by listening for a click >> over, then repeat with a thermometer, glass or pyro.   > It's open circuit, with a burnt spade terminal. Trust me, it's u/s.   But not the dome, hack into it and extract the dome. Now not constrained, you need to make sure it does not fly off , when it flips to the opposite state.

mroberds@att.net: Feb 27 01:32AM > https://en.wikipedia.org/wiki/File:Goldair_GCH200_ceramic_heater.jpg   I have a similar heater that I bought here in the US, branded Holmes, made in China. It is rated at 1500 W, 120 V, 60 Hz. As a first cut, their product support page   http://www.holmesproducts.com/service-and-support/product-support/product-faqs/heaters/general-information/heaters-general-faq.html   says the "overheat shutoff temperature" varies from 149 to 265 F, or about 65 to 130 C. Note that this covers both ceramic and non-ceramic heaters.   Taking mine apart, the ceramic core is about 3.25 x 3.5 x 0.5 inches, or about 83 x 89 x 13 mm. If yours is very different than this, then it may need a different temperature rating!   The safety switch is an "open frame" design, like the one seen in the picture you linked -   > http://www.zuglet.com/ev/saturn/images/ceramicElement.jpg   - and not an enclosed one like the KSD301 Ebay link you gave. When installed, the bimetal with contacts is about 0.125" or 3 mm away from the top edge of the ceramic core.   It is marked AUONE, AUT95P, and has VDE and USA-Canada UL component marking ("backwards RU").   Google leads me to http://www.auone.com/showproduct13.asp?ProID=1849 . The part I have looks like their "AUT-P" series (with the white plastic tab), which lets me *guess* that the "95" in the part number means 95 C (or 203 F). Again, this is _just a guess_.   Please proceed with caution. The house you don't burn down may be your own.   Matt Roberds

Mike Tomlinson <mike@jasper.org.uk>: Feb 27 03:08AM >says the "overheat shutoff temperature" varies from 149 to 265 F, or >about 65 to 130 C. Note that this covers both ceramic and non-ceramic >heaters.   A useful data point, thanks.   >Taking mine apart,   You didn't have to go to that much trouble, but thank you.   > the ceramic core is about 3.25 x 3.5 x 0.5 inches, >or about 83 x 89 x 13 mm. If yours is very different than this, then it >may need a different temperature rating!   3.5" x 3.25", so very similar. There's 4 ceramic cores with two heat levels selected by a switch (heat level 1 = 2 cores operating, heat level 2 = 4 cores operating)   Ceramic elements are PTC so self-regulating to an extent.   >Google leads me to http://www.auone.com/showproduct13.asp?ProID=1849 . >The part I have looks like their "AUT-P" series (with the white plastic >tab)   That sounds like a resettable one.   >, which lets me *guess* that the "95" in the part number means >95 C (or 203 F). Again, this is _just a guess_.   It's also right in the middle of the "65 to 130C" shutoff temperature you quote above.   Many thanks.   >Please proceed with caution. The house you don't burn down may be >your own.   Obviously, I need to choose a sensible temperature for the cutoff - too low, and it'll trip on and off all the time. There is also a thermal fuse as a belt-and-braces measure at the top of the ceramic frame. I haven't looked to see what temperature rating it is. Obviously, if that fails, it will fail open permanently.   The ceramic element is held in place in a hard plastic frame, so isn't going to be allowed to get very hot.   I'll try a 95C switch with a temporary neon indicator on the feed to the element to see if it's cycling excessively, and go from there.   It's a nice little heater, very quiet and efficient, so worth a bit of time.   Thanks again.   -- (\_/) (='.'=) Bunny says: Windows 10? Nein danke! (")_(")

amdx <nojunk@knology.net>: Feb 26 03:47PM -0600 On 2/26/2016 9:21 AM, John-Del wrote: >> Anyone know how to get around this?   >> Mikek   > Not sure about the adapter, but most cable channels these days are letter boxed which means borders on the top.   If your Sony is set for 4:3 aspect in the HDMI input, that would give you 4 sides of black.   Try putting the Sony in widescreen mode for HDMI (assuming it isn't already)   Is there a separate setting for wide screen when using HDMI vs RF? I thought RF and HDMI would be the same, ie a global setting. To clarify, in RF mode it is full screen, switching to HDMI causes letter box. I'll poke around this evening to see if I can find something. Mikek

amdx <nojunk@knology.net>: Feb 26 07:06PM -0600 On 2/26/2016 3:47 PM, amdx wrote: > letter box. > I'll poke around this evening to see if I can find something. > Mikek   I found it! There is a screen setting in the menu of the DTA. Set it and it's good.   Thanks, Mikek

Cursitor Doom <curd@notformail.com>: Feb 27 12:42AM On Thu, 25 Feb 2016 00:36:16 +0100, Dimitrij Klingbeil wrote:   [...]   Dimitrij, I think you may have missed this I posted elsewhere so I'm re- posting it here now for you personally:   "Final update for the time being as I have to leave soon now:   That short turned out to be intermittent. I hope it was just due to something shorting out on the bench that won't happen when the casing is back on because you all know what a bitch it can be to trace intermittent faults. Anyway, that fault has now disappeared, so I took some voltage measurements before the 20W resistor got to hot (from 19'C to 60'C takes about 1.50s now) and I have:   61.7 12.7 5.8 0 -5.8 -12.7 -62.4   This is with the psu board plugged into the scope and all power connections made except for the VHT stuff.   The correct figures according to the manual should be:   60 12.7 6 0 -6 -12.7 -60   So very close! Looks like the main transformer may be ok after all."   Making progress! :)

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