Re: Samsung MD55B Backlight Circuit

Thanks so much.
Yes, that circuit is what it looked like from tracing the tracks. I was just not sure about the S+ and S- lines from the Power board.
I will now experiment with the 98 salvaged LEDs to try and find out if there is an application for them.

The LCD panel on the TV is cracked, so decided to salvage for parts.
Real surprised at the neat and simple build, with the single Power Supply board that includes driver for the backlight.
Managed to reclaim all 14 strips with total of 98 LEDs.
It appears that Leds are connected in series and strips are split 4 & 3 in parallel.
The connector is labelled D1+, D1+,S+,S-, NC,NC, D1-, D1-.
Just not sure what S+, S- are as it appears the bank of 3 strips go to those terminals.

Re: Garage Door Opener Merlin 5580A



One could reasonably expect that service technicians would know the common faults and at least do a bit of troubleshooting.
All the guy did was check power and operate the remote. When there was no response or click it was obviously a receiver/transmitter problem.
It just seemed ridiculous to scrap a perfectly operating unit just for that....

Re: Garage Door Opener Merlin 5580A

What a surprise! There was one capacitor that had slight bulge on top, so decided to replace it. Only had 1000 mF leftover from previous Samsung repair so put that in and guess what? It worked.
The opener responds to remotes perfectly! The blue Lelon is the defective cap in the attached photo....

Re: Garage Door Opener Merlin 5580A

Yes, already eliminated battery problem as there is no response to wall remote either. Even called Garage Door Service. They wanted to install new system and said the unit has been superseded. It was only installed 8 years ago.
Anyway went to local hardware depot got and installed a new DIY unit.
Just want to tinker with this before giving away as its a sturdy unit with metal chain.
Could only attach 1 photo earlier so photo of boards attached here....

Hope its ok to start thread on this topic here.
We went away on holiday for 2 weeks and not return there is no response when remote button is pressed.
Attached are photos of the internal guts and the main board and power board.
There does seem to be any obvious failed components
I'm wondering where to begin troubleshooting....

Re: New Members - please post your introductions here

Hi,
I found Badcaps while looking for info on identifying the EEPROM on a Palsonic 80 cm TV/ DVD Combo. Not much info online on that brand.
Have taken to salvaging discarded units after successfully fixing a 46" Samsung that had been tossed out. It had Bad caps and I found out just by using Google!
I have always been interested in Electronics and it dates back to days of valve radios.
Recently, I've built a HTPC and an i5 PC.
My latest project is to build a fridge door alarm using Ard...