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Andrew,

Another goofy question: would linear loading work with an end-fed wire?

Jock Elliott wrote: ↑Thu Sep 15, 2022 2:05 pm Andrew,

Another goofy question: would linear loading work with an end-fed wire?

well, never tried it, but yes it should work; although in my humble opinion it won't make much sense for an endfed

Here's my situation: I planned to run the antenna underneath the plastic rain gutter and run the downlead behind the downspout. Underneath the ladder is a strip of concrete sidewalk. The radio room is behind the two windows all the way to the right.



To the south are powerlines.



and in the trees directly facing where I took the first picture are more powerlines.



So that's the situation.

Cheers, Jock

Jock, seeing that green yard, my first thought went to a LoG antenna

http://www.kk5jy.net/LoG/

it can be built using the nooelec 9:1 or an homemade (see the above link) transformer; as for gutters, having some approx measures would help, least it say that I saw the possibility of installing a half gazillion RX antennas there

The LOG antenna idea is intriguing.

Measurements:

- Left corner of house to downspout: approx. 16 ft
- Downspout to right corner of house: approx 19.5 ft.
- height of gutter above ground at downspout: approx 10 feet

Cheers, Jock

Jock Elliott wrote: ↑Sun Sep 25, 2022 9:05 pm The LOG antenna idea is intriguing.

Also since it will be invisible and won't be an obstacle and since it will effectively reduce the noise a lot on lower frequencies

- Left corner of house to downspout: approx. 16 ft
- Downspout to right corner of house: approx 19.5 ft.
- height of gutter above ground at downspout: approx 10 feet

So you may have an horizontal "T" section with two "arms" of about 15ft each and the leg of the "T" will go (slightly sloping) from center (downspout point) to ground, there you may place a ground stake and connect your 9:1 between the "T" leg and a short wire connected to the stake, from the 9:1 you'll then run the coax to the shack where you'll connect it to your preselector/preamp unit; but before going for the "T" I'd give the LoG a try, also since nothing forbids you from having both antennas installed

as for the T antenna, an alternate config (if you aren't going to lay down a LoG) may be the one shown in the image below
the leg of the "T" goes down to some inches above ground, there it is connected to the BalUn, the other binding post of the BalUn goes to some radials spread around on ground, the gain of such a system will be around -24dBi at 1MHz with the lowest takeoff angle at 5° from horizon (good for DX), adding a preamp (e.g. the one inside your preselector) will raise the gain enough, such an antenna will have omnidirectional reception with vertical polarization and low takeoff angle and will cover the range going from a few KHz up to around 30MHz, being vertical it won't be so "quiet" but may be worth a try, the alternative as I suggested, may be a Loop on Ground which will serve you well from lower frequencies up to around 20MHz, the pattern and gain of the antenna is shown in this image

"Also since it will be invisible and won't be an obstacle and since it will effectively reduce the noise a lot on lower frequencies" -- music to my ears.

Once a year, we get winter here at my location. I don't suppose snow and/or ice will affect the performance of the LOG?

Jock Elliott wrote: ↑Mon Sep 26, 2022 10:18 am "Also since it will be invisible and won't be an obstacle and since it will effectively reduce the noise a lot on lower frequencies" -- music to my ears.

Once a year, we get winter here at my location. I don't suppose snow and/or ice will affect the performance of the LOG?

Snow won't affect the LoG as for noise, check out these

https://youtu.be/wMb8i5QajW0?t=715

https://youtu.be/e0WvIxoU0LI?t=245

and this too

https://swling.com/blog/2020/12/tom-bui ... d-antenna/

all in all, a length of insulated wire is easy to source, add 4 or more plastic stakes to keep the wire down in the grass and a 9:1 BalUn and you'll have a LoG changing the shape will only alter the pattern but the antenna will still work, size isn't particularly critical, either, the original one is fine, making the antenna larger will improve performance at lower frequencies but reduce the max usable frequency, but if one has a second antenna for the "higher" frequencies (e.g. a "SULA" ), increasing the LoG size may be an idea

Oh and in case you think you may have problems when mowing the lawn, the simplest solution is to pick 4 pieces of garden hose, slide the LoG wire inside them, the free portions of wire will then be the ones at corners hold on ground with the plastic stakes and the hose will protect the wire and avoid issues when mowing the lawn

Also, as for snow, check this out

https://tapr.org/loop-on-ground-log-antenna/

see some snow, by chance ?

Jock, here are some coarse ideas which you may consider



from left to right, top to bottom; the LoG, the Marconi T, a miniwhip and an inverted L, sizes aren't to scale, just to give you an idea of the general setup