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Author Topic: HF Antenna in an apartment w/o balcony  (Read 1381 times)

KD6VXI

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Re: HF Antenna in an apartment w/o balcony
« Reply #15 on: November 15, 2022, 07:18:48 AM »

Capacitive coupling.
Duct tape a metal plate on the outside of the glass.  Another plate on the other side of the glass.  Connect a random wire outside and a tuner inside.
You can determine the sizes needed with the ARRL Handbook formulas.
I found some 5x7 inch aluminum at the local hardware that worked OK, but this depends on the frequency and the glass thickness.
Oh, and the newer treated glass has more loss than the old single plate kind.  Sometimes you have to work with what you got!
Good luck with the project!

-Mike.

Good idea, but if it's stucco or cement, you are dead in the water.

Cement is not a good dielectric.  Stucco uses a mesh (pretty much chicken wire on steroids).

--Shane
WP2ASS / ex KD6VXI
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KB1GMX

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Re: HF Antenna in an apartment w/o balcony
« Reply #16 on: November 15, 2022, 08:21:54 AM »

Ignoring some of the total idiot responses.

Noise is the greatest enemy.

First 20M, that 33ft (give or take) so making that a square
along the ceiling means any room larger than 8.5ft square
has enough perimeter, feed it as dipole and trim for
resonance..   Obviously that is almost a closet.  Average
is 12x14 room (52ft) that nearly large enough for a 40M
bent dipole. Let the ends go vertical to make 66ft.  Also
possible is a 44ft doublet fed with parallel wire (Twinlead
or ladder line) and a tuner and likely good for 40 through
10M.

The real show stopper is noise but some bands may be
better than others.  Strictly case by case as to what
bands are quieter.  Try everything!

Power even at such close space under 20W is not
exceeding  exposure limits for HF.  The usual
problem with  higher power is not user exposure
but getting into  stereos and computer speakers
or fire alarms.  QRP helps, good RX is critical.

Be very willing to experiment.  Closed loops (fullwave)
are doable for 15, 12, and 10M with the average room
size  and as we ascend the solar cycle they may be good
bands for smaller antennas.  Generally they tend to be
less impacted by noise.

One last thing wire diameter for larger antennas is not
a limitation.  So #28 magnet wire hidden outdoors with
similar fine wires as "twin wire" feed can work very well.
Suggestion is Polystealth #26 guage as its durable and
grayish black.  The hard part with outdoors antennas
is installing without being seen installing it.  As to cable
to the outside RG174 is small about 1/8 inch, getting that
around a window its frame or other ways is trivial.  Twin
wire is easy, open window, close on it, exception is
metallic window frames.

As many suggest, keep it a low key thing, most people
have no understanding and will blame you for their fish
dying and everything else.


Allison
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N4MJG

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Re: HF Antenna in an apartment w/o balcony
« Reply #17 on: November 15, 2022, 09:03:07 AM »

i use buddiepole no problem  !
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JACKIE GREEN

KE0VT

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Re: HF Antenna in an apartment w/o balcony
« Reply #18 on: November 15, 2022, 11:01:40 PM »

I have Isotron antennas in the attic. They work pretty well. You can feed 3 with one coax. 20 meters is 21 1/2 " long and about 5" wide,  10 and 15 are smaller. They take up to 500 watts indoors and need no radials. Mount on an aluminum or PVC mast. See K1CRA store or Bilal Co in Colorado.
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VE6SH

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Re: HF Antenna in an apartment w/o balcony
« Reply #19 on: November 16, 2022, 06:24:50 AM »

Do you park your car outside? Why not install a n HF radio and antenna in your car and remote into the radio from the apartment? I know a few people that are doing that here. Yes, you would obviously need to watch the battery use (in Canada many outside stalls have AC outlets for plugging in your block heater).

Tim VE6SH
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ONAIR

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Re: HF Antenna in an apartment w/o balcony
« Reply #20 on: November 17, 2022, 10:39:45 PM »

Do you park your car outside? Why not install a n HF radio and antenna in your car and remote into the radio from the apartment? I know a few people that are doing that here. Yes, you would obviously need to watch the battery use (in Canada many outside stalls have AC outlets for plugging in your block heater).

Tim VE6SH
   Interesting!  Could also work well with a Tesla or other EV!
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KK4GGL

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Re: HF Antenna in an apartment w/o balcony
« Reply #21 on: November 18, 2022, 01:38:28 PM »

I have Isotron antennas in the attic. They work pretty well. You can feed 3 with one coax. 20 meters is 21 1/2 " long and about 5" wide,  10 and 15 are smaller. They take up to 500 watts indoors and need no radials. Mount on an aluminum or PVC mast. See K1CRA store or Bilal Co in Colorado.
Do you have a common mode choke on the feed line?
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73,
Rick KK4GGL

KD7RDZI2

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Re: HF Antenna in an apartment w/o balcony
« Reply #22 on: November 20, 2022, 05:41:32 AM »

I would try a tuner like https://mfjenterprises.com/products/mfj-16010 and the longest wire as possible.
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WA3SKN

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Re: HF Antenna in an apartment w/o balcony
« Reply #23 on: November 20, 2022, 08:07:44 AM »

I.m not so sure about the cement and stucco windows... my idea was for glass.  However, you will want to get a wire outside if possible.  Not sure of the possibilities without seeing the situation.  When are you moving?

-Mike.
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