From: Coote, Jay (JCoote@ci.arcadia.ca.us)
I am thinking about building a Z Match from scratch (or the kit) based
on ZM-1 and ZM-2 schematics and test data someone was kind enough to
send me....but had some questions:
1. Are there values which can be changed for 160 meter coverage,
2. What is the best type of capacitor to use for the fixed value
3. I wonder if an air-core inductor with the same values as the
T-130-2 core as seen in the ZM-1 or ZM-2 would help with efficiency?
(Using AL - uH formula for the toroid allows
you to take the number of windings in the project and figure the
value in uH for your own air-core coil)
4. How does one measure balance in a resistive load on the output-
use a center tap load to ground and E2 on each end to ground
using a scope and RF probe?
5. How does one measure efficiency in "odd" resistive loads (100,
300, 800 ohms..etc)-
Check E2 across the load using a scope and RF probe?
>From what I've read, it looks like the Z-match would be a good low-loss
antenna tuner for field, travel and stealth QRP. I'd appreciate any
comments and discussion.
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