# 3 signals thru 1 probe to a C.R.O

#### itsmyturn

Joined Feb 15, 2005
16
HELLO ANYBODY !!!!!!!!!!!!!!!!!!!!

I HAVE TO SHOW 3 SINUSOIDAL SIGNALS ( CLAMPED TO DIFFERENT D.C LEVELS) SIMULTANEOUSLY ON A C.R.O USING A SINGLE PROBE. HOW CAN I MAKE IT POSSIBLE.

SECONDLY HOW CAN I GENERATE AN EXACT PHASE DIFFERENCE OF 90 DEGREES.

#### 1000MFD

Joined Dec 5, 2004
4
Originally posted by itsmyturn@Feb 15 2005, 06:59 PM
HELLO ANYBODY !!!!!!!!!!!!!!!!!!!!

I HAVE TO SHOW 3 SINUSOIDAL SIGNALS ( CLAMPED TO DIFFERENT D.C LEVELS) SIMULTANEOUSLY ON A C.R.O USING A SINGLE PROBE. HOW CAN I MAKE IT POSSIBLE.
SECONDLY HOW CAN I GENERATE AN EXACT PHASE DIFFERENCE OF 90 DEGREES.
[post=5342]Quoted post[/post]​
If cross-coupling back from the load is not an issue, you can make an analog "AND" using resistors (90Kohms/10Kohms for illustration, you may choose lower resistance, just make all three the same if they are 'nominally' in the same voltage range)... The 90Kohms/10Kohms makes a 10:1 voltage divider.

AC1 --- 90Kohms -----
|
AC2 --- 90Kohms ------------------------ C.R.O. high impedance input
||
AC3 --- 90Kohms -----10Kohms
`|
Common (gnd) ----------------------------- C.R.O. signal ground

For your second question, tis an exercise.... keep in mind the phase will be frequency-dependent ifyou choose to use a passive circuit. Good luck with your homework.