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is this a resistor

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bilbo

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my old akai amp played up recently. on inspection i found a component i'm not familiar with. it looks like a resistor .the body is pink in color with one green band. my local electronic store could not help. the component is physically broken and needs to be replaced. is this a zero ohm resistor or an other component. amp is from the 80's
 
If it's from the 80s then it might be a diode. A picture would help.

Mike.
 
photo attached
 

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I've not seen a diode with the band so near the centre. The band is usually at one end to mark the cathode. You said the original was physically broken, is the picture of another similar item on the board? Are you able to unsolder it and test it?

Mike.
 
Looks like a jumper for a single-sided circuit board. Look on the other side of the board to see if a track goes between the pads.
 
no track underneath. but on the board under the component is a broken white line. close by is a bridge with continuous white line under neath. does that help. all other components are marked r c t etc but this one isn't as you can see from photo
 
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A resistor with a single black band is a zero ohm jumper. Yours is green band.
A diode would have a single band but usually not close to the center.

The diode could be marked improperly ( not close enough to the end), or,
The black band could have faded to green (not likely since most black pigment is carbon-black and fades to gray)

Easiest thing to do is have someone with a board measure resistance in both directions.


Here are the black-banded zero ohm resistors that came on my 16-channel selector box.


A9E19674-C46B-462D-8B5A-8E4BD23837B6.jpeg
 
How much is that bet Bert? I'll take that bet!View attachment 112072
I would not. I've used those zero-ohm jumpers in three different package sizes, and all of them have a black band dead-centered, not some other color even a little bit off. Plus, the end caps look a bit different. Could be a way way way off-brand jumper, but my history is against it.

OTOH, no reference designator . . . . .

ak
 
I also think it's a jumper. Measure it with an ohm meter.
 
Could the broken line underneath it be a clue? A fuse maybe? Whatever it is, being physically broken suggests massive overload so probably something downstream gone bad.

Is it possible to trace the circuit?

Mike.
 
A broken line ceratinly implies its just a piece of wire, if so and it is broken you'll probably be able to see the wire inisde.
If there is abother component on the board the same you could unsolder one end of it and check it with a multimeter set to diode check, if you get the typical 600mv forward diode drop its a diode, if you get close to 0v then its a link.
 
Why would a broken line imply a wire? Surely a solid line would imply a wire. It could be something as ridiculous as a lightning arresting spark gap for all we know.
Knowing what it's connected to could help.

Mike.
 
I have some of those, my meter says 0 ohms. I took 1 apart to see what is inside = about 10 turns of #28 copper wire.
 
Look at the OP's photo in post #4. There is a white silkscreened line under the component. But nothing to mark polarity as there would be for a diode.

My money is still on a zero-ohm jumper, but I might concede it could be a fuse. In an EEVBlog video I watched last night, Dave pointed at a white square SMT component with a green circle and said "Yes, I checked the fuse." But a fuse should have a reference designator. A replacement for a piece of wire might not.....
 
Some cameras do not like to make anything pure black when the flash is on.
The green could be a color correction issue even though someone looking at the real part would say it is black.
 
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