Resistor Identification - Lead Melted

Thread Starter

thimper300zx

Joined Mar 4, 2018
6
I know how to read color bands for 4 band resistors -- but the colors vs. measurements on these ones have me at a loss. The up/down positioned resistor initially I think RED/BLACK/BROWN/GOLD, but it's measuring 97.8 ohm (it is damaged and might be reading differently). I have another of the same resistor in another unit and it's reading 98.3. The first and third bands in particular don't look the same shade -- I'm thinking the first is RED or BROWN, and the 3rd is BROWN or BLACK. A 100 ohm should be BROWN/BLACK/BROWN/GOLD.

The 2nd (left/right) the far left (tolerance) is Gold (not so obvious in photo). The 3rd seems obviously orange. But the first and second look black (which would make it zero ohms). It reads 150 ohm but that isn't even possible with an orange 3rd. I also have another of these, but it's more damaged, and it's reading about 10K ohms.

 

MeSat

Joined May 16, 2019
16
Being a car amplifier, I would assume it is stereo. Is it in one of the amplifiers or part of the power input? If it is one of the amplifiers, look at the other channel and measure that one. If it is in the power circuit, see if you can trace where it goes and possibly draw your own schematic of the associated components to share with us.
 

Thread Starter

thimper300zx

Joined Mar 4, 2018
6
This is a photo of a second (of the same model amp).

But I still don't know for sure on the colors. The resistor in this second amp is way fried. I have since pulled them off the board and this one will not read consistently. If I put any pressure on the wires, the resistance will jump around. And this one is not readable (one of the bands the color is basically gone/burnt off). But, just refer to the photo in the OP.

I was given the recommendation that these two resistors both just be replaced with something 470 to 1K ohms and I should be fine. The Zeners about 1.5" to the right (ZD1A ZD1B) are shot (they were also loose in the solder points) and I will replace those. This may fix the amp(s), but it doesn't solve the mystery of these resistor IDs.

 
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Thread Starter

thimper300zx

Joined Mar 4, 2018
6
Here is a photo of the back where the bad solder points are (corresponding to the resistors and zeners). (See green dots to the right of each point)

 
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