Help identifying components
 

Even without the "variable" this can work. Use a high enough DC voltage.

There is a method with a scope, resistor and AC supply but it is much more
complex for a novice (assuming)

I got the scope, resistor(s). Variac + small transformer = variable AC
supply.

So describe away!

Thanks.

Help identifying components
 

hmmmm... Now you are pushing my memory hard!!...LOL

Let's see.

Make a series circuit with the resistor (R) at the top and the component at
the bottom. Feed the whole thing with an AC voltage supply, top to bottom.

You will need a scope with horizontal input as well as the usual vertical
input and a floating ground or full differential input somwehere. (you work
out the logic .. maybe a floating AC voltage supply would be enough)

Hook the vertical input across the resistor and the horizontal input across
the component. Maybe the grounds together in the middle of components and
floating supply are good for that??? Been a few years.

Now your vertical trace on the scope indicates current (IR drop in the
resistor).
The horizontal trace indicates voltage drop across the component.
You will get the single curve of a component tracer on your scope.

***Component curves***
**shorted = vertical line
**open = horizontal line
**resistor same as R = 45 degree line
**capacitor = circle... me thinks round indicates matching impedance with R
at 60Hz??
** inductor = circle same as cap above??
**zener no current at lower voltages = horiz. line; no voltage increase at
higher voltages = vertical line = visible knee at zener voltage - use
calibrated scales for measurement
**avalanche diode = horizonatal line with foldback and shows current
(vertical at higher end)

Try it! So simple it stinks but is very visible clue. Watch your scope
grounding.



"DaveC" wrote in message
...
I got the scope, resistor(s). Variac + small transformer = variable AC
supply.

So describe away!

Thanks.




Even without the "variable" this can work. Use a high enough DC voltage.

There is a method with a scope, resistor and AC supply but it is much
more
complex for a novice (assuming)

Help identifying components
 

On Sep 26, 7:14*pm, "Josepi" wrote:
hmmmm... Now you are pushing my memory hard!!...LOL

Let's see.

Make a series circuit with the resistor (R) at the top and the component at
the bottom. Feed the whole thing with an AC voltage supply, top to bottom..

You will need a scope with horizontal input as well as the usual vertical
input and a floating ground or full differential input somwehere. (you work
out the logic .. maybe a floating AC voltage supply would be enough)

Hook the vertical input across the resistor and the horizontal input across
the component. Maybe the grounds together in the middle of components and
floating supply are good for that??? Been a few years.

Now your vertical trace on the scope indicates current (IR drop in the
resistor).
The horizontal trace indicates voltage drop across the component.
You will get the single curve of a component tracer on your scope.

***Component curves***
**shorted = vertical line
**open = horizontal line
**resistor same as R = 45 degree line
**capacitor = circle... me thinks round indicates matching impedance with R
at 60Hz??
** inductor = circle same as cap above??
**zener no current at lower voltages = horiz. line; no voltage increase at
higher voltages = vertical line = visible knee at zener voltage - use
calibrated scales for measurement
**avalanche diode = horizonatal line with foldback and shows current
(vertical at higher end)

Try it! So simple it stinks but is very visible clue. Watch your scope
grounding.

"DaveC" wrote in message

...
I got the scope, resistor(s). Variac + small transformer = variable AC
supply.

So describe away!

Thanks.

Even without the "variable" this can work. Use a high enough DC voltage..

There is a method with a scope, resistor and AC supply *but it is much
more
complex for a novice (assuming)

Sim this in LTSpice

Version 4
SHEET 1 880 680
WIRE 64 64 -16 64
WIRE 224 64 144 64
WIRE 256 64 224 64
WIRE -16 128 -16 64
WIRE 224 144 224 64
WIRE -16 272 -16 208
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FLAG 112 288 0
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SYMATTR Value BZX84C15L
SYMATTR Description Diode
SYMATTR Type diode
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SYMATTR InstName V1
SYMATTR Value SINE(0 30 50)
TEXT -50 312 Left 0 !.tran 200m