But isn't current phase what phased arrays are all about?
73, Pete N4ZR
At 01:38 AM 4/18/2007, Michael Tope wrote:
>----- Original Message ----- From: "Pete Smith" <n4zr@contesting.com>
>
>>> > 2. if the line length is any multiple of exactly 90 degrees, its
>>>phase delay is the same as its electrical length and the phase delay
>>> > is not dependent on the VSWR on the line.
>>> >
>>> >
>>>I don't think this is true. My old memory says the length is 180 deg.
>>>
>>>73, Roger
>>
>>
>>You're right. On page 11-7 of the current edition of the ON4UN book, Fig.
>>11-6 charts phase shift vs line length for various load mismatches. For a
>>given mismatch the phase error appears greatest at 90 degrees and zero only
>>at 0 and 180 degrees.
>>
>>73, Pete N4ZR
>
>Pete,
>
>Figure 11-6 shows the "current phase shift" of a 50 ohms line
>versus electrical length for 3 cases (1 matched, 2 different
>mismatches). This is equivalent to ANGLE (Iout | Iin). With
>the 90 degree line ANG (Iout | In) <> 90 deg is VSWR <> 1.0,
>but ANG (Iout | Vin) = 90 deg for any load impedance. See
>paragraph 3.4.5 on W7EL "Current Forcing" properties of 90
>degree lines.
>
>73, Mike W4EF........................................
>
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