Am I correct in understanding that a toroidal 50:75 ohm HF UNUN can be
housed in a metal box only sufficiently large to clear the windings by
enough to prevent arcing? I'm thinking of using metal weatherproof NEMA
boxes for this purpose, but could use the plastic equivalents if that would
make a difference for losses or bandwidth.
What is a good choice of winding wire for this purpose, to handle full
amateur power over 160-10 meters, with tolerance for fairly high SWRs.
Sources?
The design in the ARRL Handbook uses compensating capacitors, but I recall
being told that if the windings are twisated before being applied to the
core, this is generally not necessary for the 50:75 ohm case. I don't have
much in the way of test equipment, so I'm hoping a cookbook solution can
give good results.
Thanks in advance for any help.
73, Pete Smith N4ZR
n4zr@contesting.com
Sometimes a tower is just a tower
--
FAQ on WWW: http://www.contesting.com/towertalkfaq.html
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
Search: http://www.contesting.com/km9p/search.htm
|