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Chuck <chuck445@yahoonospam.com>: Nov 25 10:50AM -0500 Ok, so after the awful burning up of the dimmer, it took several days for the seller to finally agree to take the 3 I originally ordered back (1 burned, 2 unused). Something to keep in mind. Take a look at seller returns. If they don't say "30 day free returns" for their policy, look for someone else! At least regarding items like this. This guy had returns but seller pays shipping, which I adamantly refused. It took several days of standing firm once I opened a case along with photos of the insides of the burned dimmer with a final threat that I would get my money back on the date eBay was allowed to "step in." That date would have been this coming Friday. The seller finally agreed. Looks like he's Chinese because he must have asked multiple times if I wanted to get it repaired or was I sure I didn't want a new one. NO, I want to return them all for full refund and you pay shipping because they are not as described and I consider them unsafe. After plugging in shipping estimates today, I can see why he was so concerned. He sent them in a cushioned bag, but not taking any chances in case he claims damaged upon return, I was going to return them in a fairly large box... at a cost of more than $50 US. Wow! Not sure what's happened and I guess I have been out of selling for a while now, but never expected a rate like that! So, I will reuse his bag, send insured, keep records and screenshots of everything and he will pay it all. If not, I will have all records for eBay if/when the time comes. All this because seller didn't have "free 30 day returns". By the way, sending them back in his bag will cost $16.90 insured.   I had a Chinese power supply arrive DOA a month ago. Seller had "free 30 day returns." I started the return process and within a few hours was the Paypal refund. Before the refund, I had received the link for the shipping label. When sellers are refunding before you send back the item, are you still supposed to send it back with the prepaid shipping label, or not? Up to now, I have sent them back.   Just some info you may find useful... or not.

"Peter W." <peterwieck33@gmail.com>: Nov 25 08:22AM -0800 More important than anything else you might do would be to leave direct and honest feedback. This may, possibly, help the next potential victim (oops, buyer, that is).   Friends do not let friends buy from China (when there is any possible alternative).   Peter Wieck Melrose Park, PA

Chuck <chuck445@yahoonospam.com>: Nov 25 11:29AM -0500 On 11/25/20 11:22 AM, Peter W. wrote:   > Friends do not let friends buy from China (when there is any possible alternative).   > Peter Wieck > Melrose Park, PA   I am considering it and it would be the first time, in the 25 years I have been registered on eBay, that I left a negative feedback. Really, this seller should have not haggled on this and refunded immediately especially after I submitted the pictures. Not being set up in the correct way, however, meant that he can't even have a prepaid label made.

Hilda Winkler <hildawinkler77@gmail.com>: Nov 24 06:40PM -0800 > Did you check for the ps on command from the main back to the power supply?   > These things "ping pong". The power supply sends the standby voltage to the main when AC is applied. The main (on command) then sends a logic high back to the power supply to turn on the rest of the supply. The power supply goes into full run and provides the rest of the voltages, including the 12V or 24V back to the main to allow full operation.   > All we know right now is that you have the first step: the standby voltage. Push the power button and see if there's any change on the command line back to the power supply. If not, best odds is that the BGA got torched during the reflow.     with AC applied. I jumped standby pin to pwr_on pin with a 270 ohm resistor. I got 12v on 3 pins of the power supply. TV did not power on. No voltage going to the backlights.??? so i guess the BGA is fried???

Lisa Court <lisacourtcondos@gmail.com>: Nov 25 06:08AM -0800 > > These things "ping pong". The power supply sends the standby voltage to the main when AC is applied. The main (on command) then sends a logic high back to the power supply to turn on the rest of the supply. The power supply goes into full run and provides the rest of the voltages, including the 12V or 24V back to the main to allow full operation.   > > All we know right now is that you have the first step: the standby voltage. Push the power button and see if there's any change on the command line back to the power supply. If not, best odds is that the BGA got torched during the reflow. > with AC applied. I jumped standby pin to pwr_on pin with a 270 ohm resistor. I got 12v on 3 pins of the power supply. TV did not power on. No voltage going to the backlights.??? so i guess the BGA is fried???   From my chair, yes. Again, BGA reflow is a bit of an art (and maybe some Voodoo as well). I admit I don't have a handle on this either but since replacing BGA chips on TV mains are not economical, so a reflow is get out of jail free card if it works.   No new mains have been available for that series since shortly after the TV was first made, and most of that model have issues with the main board. Since the board has several known issues, a used main board is a crap shoot. You may be back in the same boat in 6 months if you install a used board. I'd troll around ebay and wait for a cheap one that has a guarantee attached. That model is a good performer (local dimming as well), but it had issues for sure.

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Nov 25 08:31AM -0500 On 11/16/20 5:14 PM, Eli the Bearded wrote:   > Elijah > ------ > does still has a decent furniture thrift store near by   My theory is that if my better half still puts up with me, she can't really be that picky. ;)   Cheers   Phil Hobbs

John Robertson <spam@flippers.com>: Nov 24 11:36AM -0800 On 2020/11/24 6:42 a.m., Peter W. wrote:   > https://www.ebay.com/itm/20Amp-Variac-Transformer-Variable-AC-Voltage-Regulator-Metered-2000VA-0-130V/124023830503 This device does not. Note the difference in cost. That cost is not only for those obscene profits on the part of the manufacturer, but also for proper design, proper testing, basic quality control, insurance and all the other unnecessary niceties avoided by the resellers and their suppliers. So, the bottom line is that you get what you pay for, with all the consequences attached thereto.   > Peter Wieck > Melrose Park, PA   Thanks for taking the time to reply to such depth. I will be flagging this so it is easily retrieved in the future!   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."

Chuck <chuck445@yahoonospam.com>: Nov 24 04:05PM -0500 On 11/24/20 2:36 PM, John Robertson wrote:   > Thanks for taking the time to reply to such depth. I will be flagging > this so it is easily retrieved in the future!   > John :-#)#   I appreciate this too. Further investigation on my part might shed light on a cause for both of my dimmer failures: too high of input voltage! Even though advertised as 12-24VDC input, I tend not to trust this figure and, after looking at the components inside, I think it's 12V, period! Unfortunately, the driving supplies I had been using for this were more like for standard Ham radio, 13.8 VDC. Perhaps this higher voltage could not be handled by the dimmer components.

Phil Allison <pallison49@gmail.com>: Nov 24 02:07PM -0800 Chuck wrote: ============ > 12V, period! Unfortunately, the driving supplies I had been using for > this were more like for standard Ham radio, 13.8 VDC. Perhaps this > higher voltage could not be handled by the dimmer components.   ** You have an obvious overheating failure of one mosfet in a parallel pair. As mosfets heat up, the on resistance increases by a factor of 2 or more. So the temp rise does as well. Having no heatsink at all in that device is nuts. Bad design, buy something else.     ...... Phil

Phil Allison <pallison49@gmail.com>: Nov 24 02:38PM -0800 Chuck wrote: > 12V, period! Unfortunately, the driving supplies I had been using for > this were more like for standard Ham radio, 13.8 VDC. Perhaps this > higher voltage could not be handled by the dimmer components.   ** You have never posted what PSU voltage you have been using ???   The rating of 12-24V applies to the LED array it is driving.   You cannot use a 24V supply, connect a 12 V LED array and set the control half way.     ..... Phil

Chuck <chuck445@yahoonospam.com>: Nov 24 07:35PM -0500 On 11/24/20 5:38 PM, Phil Allison wrote:   > The rating of 12-24V applies to the LED array it is driving.   > You cannot use a 24V supply, connect a 12 V LED array and set the control half way.   > ..... Phil   So, it could have been either lack of heatsinking, my 1.8V overvoltage, or both?   Thanks for the clarification on the 12-24V. I certainly didn't know this!

Phil Allison <pallison49@gmail.com>: Nov 24 05:04PM -0800 On Wednesday, November 25, 2020 at 11:35:21 AM UTC+11, Chuck wrote:   > > ..... Phil   > So, it could have been either lack of heatsinking, my 1.8V overvoltage, > or both?   ** Was you 8A current figure when the controller was set to full ?   > Thanks for the clarification on the 12-24V. I certainly didn't know this!   ** Yes - it is missing data in the advertising.   A PWM controller is *not* a voltage regulator, merely a " time division" current reducer.   If the voltage is a little high, the current will be way higher.     ...... Phil

"Peter W." <peterwieck33@gmail.com>: Nov 24 09:12AM -0800 Glad to be of help. Every so often, I will go ahead and actually read a manual, knowing full well that it is against the Male Code.   Peter Wieck Melrose Park, PA

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