There is no possibility tat board will work. https://www.electro-tech-online.com/attachments/c1100c-aee-service-p-04165600-1-pdf.128765/#page=13 , there is no power going to the LEDs.
Anyway, expect it's 5V. That would make the LED current about 1 mA, Usually, it would be around 10 mA, but there are some high efficiency LEDS that can use 1 mA.
Looking guarantees nothing. Freeze spray isn't a bad diagnostic too;
Resistor looks like it has a gap.
I actually have this https://www.circuitspecialists.com/bk5000.html as a re-work station. Surface mount basically forced me to get something.
It's not bad, but it has some glitches.
1. You can use solder/desolder at the same time.
a) I'd buy an integral desolder tool, maybe eventually
2. The desoldering tool doesn't work extremely well.
3. The soldering iron elements pop out easily.
4. No circuit diagram. helps when troubleshooting head problems.
4a. Had to figure out what it was.
5. The desoldering tool hung up in the holder
5a. I bought a reamer to fix that
Why am I saying this? Because many times you have to decide to purchase tools or have someone else do it.
I dug a drainage trench. I bought a used Bosch demolition hammer and re-built it. It was like$700-$900 new. I paid someone to remove the chuck. In the process I found that there are separate maintenance manuals available for Bosch stuff. I had to buy a clay spade as well which is great for digging. It gets used once and a while.
I just bought $225.00 of optician's tools. Why? I want to maintain my own glasses. The opticians keep destroying the frames. I have about 5 of the same frames. I like to have 3 pairs of glasses. Pair #1: trivex lenses, normal bifocal; paur 2. glass lenses, normal bi-focal and pair 3; glass lenses, high bi-focal (computer glasses). All have an AR coating. plastic doesn't require UV.
Back to your problem. LEDs have a forward voltage drop depending on color. They also have a range. Vf also determines how bright they are relative to another LED. Mcintosh may bin them to get even brightness or the LEDs have good factory tolerances. Chalk up a reason for a new board.
Typically you series connect LED's and have some wiggle room left over. e.g (5-2.2*n)/2.74k is about 1 mA. n=1 LED, 2.2 because it's green.
Most multimeters have a diode test mode which measures the voltage drop. I can also supply 5V externally after determining I can do so safely. My fluke 77, one of my meters (fluke 77) only goes to 2.0 volts, so that won't work.
You have the wiggle test available.
For the job, this https://www.amazon.com/Antex-G-3U-Watt-Pen-Sized-Soldering/dp/B00FS78QF6 iron would be suitable. I had one like it at work.
if your in the US and particularly if your nearby, I'll do it for you. If i get hit my a car in the time frame, you can buy a board.
Anyway, expect it's 5V. That would make the LED current about 1 mA, Usually, it would be around 10 mA, but there are some high efficiency LEDS that can use 1 mA.
Looking guarantees nothing. Freeze spray isn't a bad diagnostic too;
Resistor looks like it has a gap.
I actually have this https://www.circuitspecialists.com/bk5000.html as a re-work station. Surface mount basically forced me to get something.
It's not bad, but it has some glitches.
1. You can use solder/desolder at the same time.
a) I'd buy an integral desolder tool, maybe eventually
2. The desoldering tool doesn't work extremely well.
3. The soldering iron elements pop out easily.
4. No circuit diagram. helps when troubleshooting head problems.
4a. Had to figure out what it was.
5. The desoldering tool hung up in the holder
5a. I bought a reamer to fix that
Why am I saying this? Because many times you have to decide to purchase tools or have someone else do it.
I dug a drainage trench. I bought a used Bosch demolition hammer and re-built it. It was like$700-$900 new. I paid someone to remove the chuck. In the process I found that there are separate maintenance manuals available for Bosch stuff. I had to buy a clay spade as well which is great for digging. It gets used once and a while.
I just bought $225.00 of optician's tools. Why? I want to maintain my own glasses. The opticians keep destroying the frames. I have about 5 of the same frames. I like to have 3 pairs of glasses. Pair #1: trivex lenses, normal bifocal; paur 2. glass lenses, normal bi-focal and pair 3; glass lenses, high bi-focal (computer glasses). All have an AR coating. plastic doesn't require UV.
Back to your problem. LEDs have a forward voltage drop depending on color. They also have a range. Vf also determines how bright they are relative to another LED. Mcintosh may bin them to get even brightness or the LEDs have good factory tolerances. Chalk up a reason for a new board.
Typically you series connect LED's and have some wiggle room left over. e.g (5-2.2*n)/2.74k is about 1 mA. n=1 LED, 2.2 because it's green.
Most multimeters have a diode test mode which measures the voltage drop. I can also supply 5V externally after determining I can do so safely. My fluke 77, one of my meters (fluke 77) only goes to 2.0 volts, so that won't work.
You have the wiggle test available.
For the job, this https://www.amazon.com/Antex-G-3U-Watt-Pen-Sized-Soldering/dp/B00FS78QF6 iron would be suitable. I had one like it at work.
if your in the US and particularly if your nearby, I'll do it for you. If i get hit my a car in the time frame, you can buy a board.
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