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How do you bench test a shifting diode 1971 60 HP Johnson

tay65lor

tay65lor

New member
Hey,
Could anyone tell me how to bench test a shifting diode with a multi meter.
I have a shifting diode from a 1971 60 hp Johnson outboard. It has three leads coming off it Yellow, Yellow/Gray stripe, Purple/Green stripe.
 
Varies according to your multimeter. Analog? Digital?? Digital with diode test? Anyway, any diode is tested by connecting the meter leads to each end of it, then reversing the leads. Should show a high resistance in one direction and a low resistance in the other direction (or a beep or tone on some meters) You have two diodes in that one glob. Yellow and purple/green wires are one diode and yellow/gray and purple/green are the other one. Test each one separately.
 
Red meter lead on Purple/Green... Black meter lead on Yellow, then on Yellow/Gray.

Now, reverse the leads... Black meter lead on Purple/Green... Red lead on Yellow, then on Yellow/Gray.

You should get a reading in one direction... none in the other.

It doesn't matter what the reading is... just matters that you do or do not get a reading.
 
Hoo boy, kim, that is true, but will confuse a bunch of people. Let's explain a little further. It is correct that the current flows from neg to pos. That is the electron theory of electricity. That's the way I learned it in my TV repair course back when TV's had vacuum tubes, and necessary if you have any hope of understanding how a vacuum tube works. HOWEVER it is also true that many (most) people use the conventional theory that states that current flows from pos to neg. I asked my daughter-in-law about this. She is an electrical engineer in the largest nuclear power plant in U.S.. She agreed with what I just said, and further said that the power plant uses the conventional theory because it is easier for most people to understand because that is the way most people THINK it is. So there ya go. Personally, I had a heck of a time training my mind to think in terms of the electron theory, so I guess the power plant's way of doing it is ok.
 
I didn't mention this, buy my son is in college and they are teaching him the conventional theory also. Are we obsolete along with the vacuum tubes?
 
Thanx again joereeves you came through again with a simple answer to a simple question lol. Ill check that when i get home tonite
 
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