At 08:03 AM 2001-07-26, you wrote:
>Thanks. I think the original article did use a hybrid coupler.
Here is a little more info now that I am back from my errands.
I have a few extra minutes so I could dig up some info for you.
There are no cookbook directions to do the hybrid phase shifter.
But check out FIG 10A (page 78) in Ham Radio March 1983.
This is the main reference to what you need in order to do the
phase shift network with a hybrid. And the article listed below
on capacitively-coupled hybrids shows how to build a 90 deg
hybrid using two caps and two pieces of coax. I have built
a couple of these for high power and used them to combine
two HF amps. RG-213 and doorknob caps will work FB
at HF for the legal limit.
For other ham references to hybrids check out the following.
April and May 1984 Ham Radio article on Branch-Line Hybrids
June 1982 Ham Radio on the Hybrid Coupler
October 1983 Ham Radio HF Hybrids: A Second Look
March 1983 Ham Radio Capacitively Coupled Hybrids
August 1983 Ham Radio The Hybrid Ring
January 1982 Ham Radio Wilkinson Hybrids
March 1978 Ham Radio High-Frequency Hybrids and Couplers
July 1970 Ham Radio Microwave Hybrids and Couplers
August 1972 Ham Radio N-Way Power Dividers and 3-dB Hybrids
October 1979 QST Broadband Hybrid Splitters and summers
January 1978 QST Twisted-Wire Quadrature Hybrid Directional Couplers
These will give you a start--at least the ham literature sources.
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