Analog board test spare overhaul

[LaPorta]

I’m overhauling a Plus analog board to be the rig for my test stand. Previous owner said it didn’t work. I’ll recap obviously in case it is just that. I noticed something I found peculiar: I’ll admit, I never really understood what this iron ring with wires is except to maybe generate a magnetic field? However, I’ve never seen it with clipped, disconnected ends. Is that normal?

 

[marcelv]

the green is the ground wire which in your case is connected directly

 

[cheesestraws]

I’ll admit, I never really understood what this iron ring with wires is except to maybe generate a magnetic field

I mean that looks kind of like a common mode filter thing, but what on earth is the earth wire also doing wound around it?

 

[LaPorta]

Filter, yes, that perhaps too. The thing I don’t get is why there is a green ground wire, like others that have the ground embedded in it, that is clipped on both ends  (the copper nubs at the ends), and the actual ground wire is soldered directly to the ground terminal of the power cable connector. Did someone mod this thing to just bypass the ring, or what happened here?

 

[techknight]

yea its just a filter choke. kind of a bad one at that since you already have one just above it. Oh well, wanted to make sure it passed FCC checks regardless.