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Technical Topics => Equipment => Topic started by: OgreVorbis on May 27, 2020, 0411 UTC

Title: Outdoor tuner or switch
Post by: OgreVorbis on May 27, 2020, 0411 UTC
I'm trying to figure out how I'm going to make my inverted L antenna switchable. This may seem simple, but let me elaborate.
My antenna as is, is just an L with a shunt coil to ground. This allows me to operate very well on only one frequency +-20kHz. Now I want to make another system to make this antenna usable on shortwave with a tuner.

I could just remove the shunt and make a full fledged L or Pi network tuner outdoors. This will probably be very time consuming with the weather proofing, etc. So basically what I think I want to do is put a switch outside to switch out the inductor and then use a normal ham tuner indoors. I know I could probably just re-tune the outdoor shunt inductor, but this will be a hassle to get it right with the tuner indoors also hooked up to it.
Title: Re: Outdoor tuner or switch
Post by: NJQA on May 27, 2020, 1240 UTC
Have you considered a knife switch?
Title: Re: Outdoor tuner or switch
Post by: Brian on May 28, 2020, 1916 UTC
Assuming this is low band, possibly at the top of the MW band, antenna, I'd be more concerned about how you're going to get it to work at HF.
Title: Re: Outdoor tuner or switch
Post by: OgreVorbis on May 29, 2020, 0024 UTC
Have you considered a knife switch?

I'll check that.

Assuming this is low band, possibly at the top of the MW band, antenna, I'd be more concerned about how you're going to get it to work at HF.

Just a normal ham tuner. You think it won't work?
Right here they show what happens when you transmit at higher harmonics on an L antenna. I won't be exactly on the harmonics, but very close.
https://www.qsl.net/kk4obi/EFHW%20inverted%20L.html (https://www.qsl.net/kk4obi/EFHW%20inverted%20L.html)
Title: Re: Outdoor tuner or switch
Post by: Brian on May 29, 2020, 1443 UTC
You're still going to have to match it to the transmitter. Could be a nightmare. I've never tried it so I could be talking out of my hat.