ferrite beads

[Tibuck19]

Good evening gents, I recently recycled a hole bunch of ferrite beads from a board, I was wondering is If was to add them to the base of the transistors, on the metal detectors I've made from here, would it help anything, perhaps help clean up oscillations or something ? or would it simply be a waste of time for MD? my working detectors are the geotech barracuda, minipulse plus rev-d, surf pi, tgsl maybe knowing might help better answer.

[ripsdevala]

I put it in my md as link jumper, i don't know if this correcting something or not... But its look cool tho

[dbanner]

I see many of them all over some circuit boards, but never paid attention to its use.

[dbanner]

I think they are used to supress noise, unlike bypass capacitors, ferrite beads are used in series with the power line, which means that any DC current flowing through the bead will create a voltage drop proportional to the DC resistance.
https://www.allaboutcircuits.com/tec...ferrite-beads/

[dbanner]

[QUOTE=ripsdevala;238818]I put it in my md as link jumper, i don't know if this correcting something or not... But its look cool tho [/QUOTE
I don't think this is good idea, to use merely as jumpers.

[ripsdevala]

Is there any bad side? Its lying around in my scrap pile, i see its used as jumper in the old crt scrap board.

[dbanner]

Yes, but they only appear to be used as jumpers, they actually are being used to supress noise, and although their dc resistance is low(typically below 1 ohm) their inductive reactance could be significant depending on where they are used, this could cause ringing in circuit. and not all ferrite beads are equal, there are a variety of values, depending on where they are salvaged from. Using them willy nilly is not good idea at all.

[ripsdevala]

I see, i will report here when the md is on, the beads dont have any Resistance on it, its just bare hard wire isulated with ferite.. let me try this curiosity

[dbanner]

the ones you are using for jumpers would be ok i guess, but have a look at these, they have small inductance.

[dbanner]

These are the ones to stay away from

[Tibuck19]

I think they are used to supress noise, unlike bypass capacitors, ferrite beads are used in series with the power line, which means that any DC current flowing through the bead will create a voltage drop proportional to the DC resistance.
https://www.allaboutcircuits.com/tec...ferrite-beads/

I read the same article last night just after posting this question, Yes indeed they were all on diodes. which is why I asked, they could act as chokes ? however I watch a video showing how they also clean up signals when placed on the base of a transistor.

[dbanner]

I think I understand what you are saying, using just the bead alone around the base leg of transistor, yes? Could you post link of video?

[dbanner]

After some little research, placing ferrite bead around jumpers on pcb for noise supression is common practice, it seems. But be carefull salvaging them simply to use as jumpers as some of them contain tiny inductors which could be easily mis-identified as just a straight jumper.

[ripsdevala]

Got it...

[Tibuck19]

I think I understand what you are saying, using just the bead alone around the base leg of transistor, yes? Could you post link of video?

https://www.youtube.com/watch?v=81C4IfONt3o