16-03-2024, 04:15 PM
I sort of fixed this. I got one for my old mum & dad off ebay. It was described as so dim it was barely readable and so it turned out, barely readable in the dark! I measured the voltage across A and K (referred to earlier in this thread) and found it varied when the DIM button on the remote was pressed. Measuring A and K wrt gnd I found that A was constant at about 5.2V and K increased from about 2.4V at its brightest when DIM was pressed.
Buzzing out the connector wires I found one was directly connected to K so I cut the wire (3rd from left if the red wire is on the right, I can't figure out how to attach the photos...) and soldered in one resistor and another from the K end of it to gnd (5th wire from left) to make a voltage divider and reduce the voltage at K, effectively increasing the voltage across the LED.
Initially I used two 10 ohm resistors to see if it brightened up the LED, which it did but pressing DIM gave the 4 steps of brightness as off, on, on and on. The resistors might also have got hot...
I changed the resistors to 100R in line and 330R to GND and now I get dim, less dim, bright enough and the same bright enough. This still won't be readable in direct sunlight but will be placed in a north facing kitchen. Now I just need to put stickers next to the front panel buttons so the old folks know which to press.
Buzzing out the connector wires I found one was directly connected to K so I cut the wire (3rd from left if the red wire is on the right, I can't figure out how to attach the photos...) and soldered in one resistor and another from the K end of it to gnd (5th wire from left) to make a voltage divider and reduce the voltage at K, effectively increasing the voltage across the LED.
Initially I used two 10 ohm resistors to see if it brightened up the LED, which it did but pressing DIM gave the 4 steps of brightness as off, on, on and on. The resistors might also have got hot...
I changed the resistors to 100R in line and 330R to GND and now I get dim, less dim, bright enough and the same bright enough. This still won't be readable in direct sunlight but will be placed in a north facing kitchen. Now I just need to put stickers next to the front panel buttons so the old folks know which to press.






