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AOE fig. 2.30 phasor diagram

Hi:

The phasor diagram for the constant amplitude phase shifter fig. 2.29 in AOE 2nd ed. is upside down.

That is, the Vout phasor should always point in the 3rd or 4th quadrants so that the output phase always is in the open interval (-180, 0). Ie., the Vout phase must always be lagging V1. But the text shows it pointing up in the (0, 180) degrees range, which cannot be.

A while back I did a full analysis of this thing, and concluded that the fig. 2.30 was upside down, but left it at that.

A simple LTspice analysis confirms that Vout must always be in the range of (-180, 0) degrees:

Has this little discrepancy ever bugged anyone else?

------------------------------------------------------- Version 4 SHEET 1 880 680 WIRE 192 16 112 16 WIRE 112 48 112 16 WIRE 112 160 112 128 WIRE 112 160 32 160 WIRE 32 176 32 160 WIRE 112 192 112 160 WIRE 112 304 112 272 WIRE 192 304 112 304 FLAG 32 176 0 SYMBOL voltage 112 288 R180 WINDOW 0 41 57 Left 0 WINDOW 3 24 16 Left 0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V1 SYMATTR Value SINE(0 1 50) SYMBOL voltage 112 32 R0 WINDOW 0 -65 37 Left 0 WINDOW 3 -259 97 Left 0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V2 SYMATTR Value SINE(0 1 50 0 0 180) TEXT -148 310 Left 0 !.tran 100m

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_____________________
Mr.CRC
crobcBOGUS@REMOVETHISsbcglobal.net
SuSE 10.3 Linux 2.6.22.17
Reply to
Mr.CRC
Loading thread data ...

So, where is C and R?

Reply to
John S

Sorry, I often overlook the loss of a bunch of lines copy/pasting btw. two Linux apps.

Try this:

Version 4 SHEET 1 880 680 WIRE 192 16 112 16 WIRE 256 16 192 16 WIRE 432 16 256 16 WIRE 112 48 112 16 WIRE 256 48 256 16 WIRE 432 48 432 16 WIRE 112 160 112 128 WIRE 112 160 32 160 WIRE 256 160 256 112 WIRE 320 160 256 160 WIRE 336 160 320 160 WIRE 432 160 432 112 WIRE 496 160 432 160 WIRE 512 160 496 160 WIRE 32 176 32 160 WIRE 256 176 256 160 WIRE 432 176 432 160 WIRE 112 192 112 160 WIRE 112 304 112 272 WIRE 176 304 112 304 WIRE 256 304 256 256 WIRE 256 304 176 304 WIRE 432 304 432 256 WIRE 432 304 256 304 FLAG 32 176 0 FLAG 320 160 Vo1 FLAG 176 304 V1 FLAG 192 16 V2 FLAG 496 160 Vo2 SYMBOL voltage 112 288 R180 WINDOW 0 41 57 Left 0 WINDOW 3 24 16 Left 0 WINDOW 123 24 -12 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V1 SYMATTR Value SINE(0 1 50) SYMATTR Value2 AC 1 0 SYMBOL voltage 112 32 R0 WINDOW 0 -65 37 Left 0 WINDOW 3 -259 97 Left 0 WINDOW 123 -259 125 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V2 SYMATTR Value SINE(0 1 50 0 0 180) SYMATTR Value2 AC 1 180 SYMBOL cap 240 48 R0 SYMATTR InstName C1 SYMATTR Value 1? SYMBOL res 240 160 R0 SYMATTR InstName R1 SYMATTR Value 200 SYMBOL cap 416 48 R0 SYMATTR InstName C2 SYMATTR Value 1? SYMBOL res 416 160 R0 SYMATTR InstName R2 SYMATTR Value 100k TEXT -308 238 Left 0 !.ac oct 16 1 1k

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_____________________
Mr.CRC
crobcBOGUS@REMOVETHISsbcglobal.net
SuSE 10.3 Linux 2.6.22.17
Reply to
Mr.CRC

It appears that you are correct. The last time I studied it, I didn't catch the error because I assumed V1 was at the top and V2 at the bottom.

It doesn't really bother me, however. I'll just go back to my mistaken assumption.

John S

Reply to
John S

Belay that. Swapping sources won't fix it either. I just missed catching the error, I guess. Good eye.

John S

Reply to
John S

Well, crap! Yes it will fix it. Someday I'll get my head on straight.

John S

Reply to
John S

catching

Uh-oh, you just had a human moment.

;-))

Reply to
josephkk

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