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Solid States Devices => solid state devices => Topic started by: Legalizeshemp420 on October 19, 2013, 02:43:28 PM

Title: What are these?
Post by: Legalizeshemp420 on October 19, 2013, 02:43:28 PM
I have had these for 25 to 30+ years and I never found out what they were.  Anyone out there able to enlighten me, please?

If this is the wrong forum I apologize but I could not find a general section.
Title: Re: What are these?
Post by: MileHigh on October 19, 2013, 03:11:21 PM
They might just be zero ohm resistors.  Black = zero.  Try checking with your multimeter.
Title: Re: What are these?
Post by: Pirate88179 on October 19, 2013, 03:30:02 PM
I believe MH is correct.  I googled 0 ohm resistors and got this photo.  I have never heard of them before.

Bill


Partial quote from Wiki:

"A zero-ohm link or zero-ohm resistor is a wire link (http://en.wikipedia.org/wiki/Wire) used to connect traces on a printed circuit board (http://en.wikipedia.org/wiki/Printed_circuit_board) that is packaged in the same physical package format as a resistor (http://en.wikipedia.org/wiki/Resistor). This format allows it to be placed on the circuit board using the same automated equipment (http://en.wikipedia.org/wiki/SMT_placement_equipment) used to place other resistors, instead of requiring a separate machine to install a jumper (http://en.wikipedia.org/wiki/Jumper_%28computing%29) or other wire.[1] Zero-ohm resistors may be packaged like cylindrical resistors, or like surface-mount (http://en.wikipedia.org/wiki/Surface-mount) resistors."
Title: Re: What are these?
Post by: Legalizeshemp420 on October 19, 2013, 03:36:20 PM
Very interesting indeed.  I measured them years ago and saw a dead short and never touched them again until today.

Fascinating, and thanks for the help guys. :)
Title: Re: What are these?
Post by: Pirate88179 on October 19, 2013, 04:11:05 PM
Hey, wait a minute.  I read the Wiki entry and got to thinking about it.  If they just used a piece of wire, that would add some resistance to the circuit, so they use these instead.  Does this mean that it has negative resistance such that when added to the wire used to make them equals 0?  Is there such a thing as negative resistance?

What I mean is, if you cut off the wire leads on these and measured the resistance on the thing with the stripe, would it be negative if it totaled zero with the leads?

In other words....how did they do this?


Bill
Title: Re: What are these?
Post by: TinselKoala on October 19, 2013, 07:49:52 PM
It's just a wire jumper! If you split it apart you will see that it's just a wire, straight through. It has a "body" so that it can be handled by the same automatic insertion machines as put in the resistors on a PCB, as the Wiki entry says. 
Not used much anymore, the insertion machines are better and the PCB designers avoid using jumpers whenever they can.
Title: Re: What are these?
Post by: Legalizeshemp420 on October 19, 2013, 10:07:59 PM
Quote from: TinselKoala on October 19, 2013, 07:49:52 PM
It's just a wire jumper! If you split it apart you will see that it's just a wire, straight through. It has a "body" so that it can be handled by the same automatic insertion machines as put in the resistors on a PCB, as the Wiki entry says. 
Not used much anymore, the insertion machines are better and the PCB designers avoid using jumpers whenever they can.
Only used much with single sided boards as it saved the cost of what used to be really expensive double sided making.  Hell, these days everything is going SMD because you don't need to drill holes so one less machine to deal with. :/  Wave soldering to the rescue but I hate SMD for personal hobby type work.
Title: Re: What are these?
Post by: Pirate88179 on October 21, 2013, 08:20:47 PM
Quote from: TinselKoala on October 19, 2013, 07:49:52 PM
It's just a wire jumper! If you split it apart you will see that it's just a wire, straight through. It has a "body" so that it can be handled by the same automatic insertion machines as put in the resistors on a PCB, as the Wiki entry says. 
Not used much anymore, the insertion machines are better and the PCB designers avoid using jumpers whenever they can.

Yes, I read that in the Wki entry.  I guess then, technically, they are not 0 ohms right?  I mean, that wire has some resistance to it, which is why I thought they had figured a way around that maybe.
(Room temperature super conductor perhaps?  Ha ha.)

So, these add no more resistance than the jumper wire...I get it.  Slightly false advertising though.

Bill
Title: Re: What are these?
Post by: Lakes on October 22, 2013, 04:43:08 AM
Its really a micro-ohm resistor or micro-henry inductor. ;)
Title: Re: What are these?
Post by: fritz on October 22, 2013, 05:42:56 AM
Quote from: Lakes on October 22, 2013, 04:43:08 AM
Its really a micro-ohm resistor or micro-henry inductor. ;)
Or better -  a milli-ohm resistor and nano-henry inductor.