After getting my hands on a floating 80m vertical one summer and then
getting up off the ground, I decided then and there that the 50K 200W
resistor in my junk box could do some good and maybe save me a future
surprise. Ran it that way for a few years until it came down in 85 mph
winds once night. Never got shocked again. I'm more careful now - don't
need to learn that lesson more than once...
73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com
On 6/30/22 7:45 PM, Jim W7RY wrote:
You are correct Ed.
73, Jim W7RY
On 6/30/2022 7:01 PM, Edward McCann via TowerTalk wrote:
I think the query had to do with static-relieving resistor or choke
across his antennas terminals effective at DC, if I read it correctly.
Ed McCann
AG6CX
On Jun 30, 2022, at 3:34 PM, Jim Brown <jim@audiosystemsgroup.com>
wrote:
On 6/30/2022 2:57 PM, KD7JYK DM09 wrote:
I've looked on and off over the years for a tutorial, but not had
any luck, can anyone suggest a route of study for me?
Yes. k9yc.com/RFI-Ham.pdf includes an extensive tutorial on how
ferrite chokes work, as well as a lot of other fundamental EMC
concepts.
k9yc.com/publish.htm includes two choke "Cookbooks," one for MF/HF,
another VHF/UHF. The MF/HF cookbook is based on more than a year of
winding and measuring more than a thousand chokes; the VHF/UHF
cookbook is based on Fair-Rite data sheets for specific cores. This
material has been in the ARRL Handbook for a while.
There's also an applications note on identifying RF noise by type
and providing advice on how to locate and kill it. It includes
winding guidelines for clamp-ons at the source of noise.
73, Jim K9YC
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