If a coil, or coils "beep on a FP beeper", what does that show? Thanks.
It shows that there is continuity across a circuit (not broken). It does not show whether or not a coil is shorted (wrong resistance).
I provided you with a sketch of the internal workings of a coil, with 3 separate resistance measurements to be made with an OHM meter to determine if a coil is rebuildable, in another thread.
You have so many threads regarding the same basic subject of coils that my head is spinning trying to keep up.
Best of luck
I apologize. I'll figure it out and get the stupid thing running on my own.
I will say...a seller made the statement "coils beep on a FP beeper." I had no idea what makes a FP BEEPER work.
Actually the Funprojects beeper does test for an in-range secondary resistance so it's not just a simple continuity tester.
That beep only tell you that the large secondary coil is not open.
It does not tell you if the primary coil is good or the coil will work.
The primary coil, points and/or capacitor can still be bad.
Having read up on the FunProjects beeper, I need to revise my earlier post regarding "wrong resistance"...the beeper will in fact "beep" when the secondary is in-range, just as Garnet stated. I was wrong and want to put that right...
The primary rarely goes bad beyond the solder joint at the bottom.
I'd say that the beeper does in fact give the user a good shot at purchasing a rebuildable coil (James is correct that there can be other issues, but the FunProjects literature does state that all it is proving is that the coil is rebuildable).
I use one to take to swap meets to test any old coils I might want to buy for rebuilding. I've never had one that tested good that I wasn't able to rebuild.
I am sorry I didn't see this posting or I would have answered the questions earlier but they have been correctly answered. The BEEPER thing was one of those afternoon inventions to take with me to Hershey so I could quickly test coils on swap meet tables. When people heard the sound it made they were curious what I was doing and wanted to buy it from me. I had so many offers for it that I decided to lay out a printed wiring board and started making them for sale. The beeper pays for itself by preventing you from buying a coil that can't be saved. The secondary winding is all that it checks but the primary just never is bad. The primary winding wire is so thick that it really can't break with the coil box still in good shape on the outside. Over many years I have pulled the windings out of over 3000 coils now including pulling windings from some pretty ratty "falling apart" coils and have yet to have a primary that was bad - no kidding.
User tip! - If you want to check a pile of coils and NOT help the guy next to you who is watching - put your finger over the hole in the center of the beeper and the sound will be just barely audible.
I have been thinking about making grey top hats because I get a ton of offers for my hat when I go to swap meets.
Now, a grey top hat that beeps; that would really sell!
Maybe it would tell whether the device under it still works.
You guys should write serious comedy.
Not always impossible to save coils with open secondaries. Just very very difficult. i have 2 coils that are really good except for being open secondaries. I know where they're open though. They're open at the brass button on the box.
Kep, I would still like to hear/see more about salvaging coils with open secondaries.
I'll get around to it.
Twisted these off the primary with my hands. Not sure what the recommended method is though.... You'll see the inner windings, I lost the first 80 or so innermost turns on one of them as they were slightly tangled from my rough treatment.
One of them has no flow, other allows some flow.
Connecting them to a battery showed the one that flowed could influence a compass when energized.
Wrapping the primary in a few turns of masking tape should make these a sliding fit again. And have to join the inner wires together obviously.