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K3: Indoor antennas at Dayton?

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tomb18

K3: Indoor antennas at Dayton?

Hi I was wondering if anyone has any experience with indoor antennas? I plan to present at Dayton and would like some hints as to how this works. You can contact me off list please.
73 Tom
va2fsq.com
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Gil G.

Re: K3: Indoor antennas at Dayton?

Hello,

I sometimes run a 6ft diameter magnetic loop inside.. Works pretty well. I have also had good luck with a Buddistick clamped to a coffee table! Power is usually 5W, always CW. The problem is to keep people away from the antennas, especially the magnetic loop.

Gil.
--
PGP Key: http://keskydee.com/gil.asc

> On Feb 10, 2015, at 10:04 AM, Tom Blahovici <[hidden email]> wrote:
>
> Hi I was wondering if anyone has any experience with indoor antennas? I plan to present at Dayton and would like some hints as to how this works. You can contact me off list please.
> 73 Tom
> va2fsq.com
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Doug Turnbull

Re: K3: Indoor antennas at Dayton?

In reply to this post by tomb18

Hi Tom,
I agree that for QRP magnetic loops are not bad. Dipoles in the Attic
or room also work. Get hold of RSGB book from ARRL, Stealth Antennas by
Steve Nichols G0KYA. This book is most informative.

I like the AlexLoop but you must keep it away from metal. I have used
these inside frame houses and stone houses with good results. Trouble is
that you are limited to QRP. Maybe not a bad thing if the antenna is in
close proximity.

73 Doug EI2CN

-----Original Message-----
From: Elecraft [mailto:[hidden email]] On Behalf Of Tom
Blahovici
Sent: 10 February 2015 15:04
To: [hidden email]
Subject: [Elecraft] K3: Indoor antennas at Dayton?

Hi I was wondering if anyone has any experience with indoor antennas? I plan
to present at Dayton and would like some hints as to how this works. You can
contact me off list please.
73 Tom
va2fsq.com
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Merv Schweigert

Re: K3: Indoor antennas at Dayton?

In reply to this post by tomb18

Must be something I am missing here, your going to present at Dayton a
talk about
indoor antennas and have no experience using them?

Maybe something lost in the translation I missed.

73 Merv K9FD/KH6

> Hi I was wondering if anyone has any experience with indoor antennas? I plan to present at Dayton and would like some hints as to how this works. You can contact me off list please.
> 73 Tom
> va2fsq.com
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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tomb18

Re: K3: Indoor antennas at Dayton?

Hi,
No I am presenting a software package and would like to show some signals on
the K3 indoors at Dayton. So the antenna has to be small. Transmit not
necessary!
Thanks

-----Original Message-----
From: Merv Schweigert
Sent: Tuesday, February 10, 2015 11:56 AM
To: [hidden email]
Subject: Re: [Elecraft] K3: Indoor antennas at Dayton?

Must be something I am missing here, your going to present at Dayton a
talk about
indoor antennas and have no experience using them?

Maybe something lost in the translation I missed.

73 Merv K9FD/KH6

> Hi I was wondering if anyone has any experience with indoor antennas? I
> plan to present at Dayton and would like some hints as to how this works.
> You can contact me off list please.
> 73 Tom
> va2fsq.com
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]
> .
>

Merv Schweigert

Re: K3: Indoor antennas at Dayton?

Gotcha Tom, thanks, it did not come through like that.
Should be a number of guys on here using small indoor antennas,

I used one for several years in 2001 while living in a condo on the beach,
it was 44 foot of wire taped to the ceiling of the second floor condo, fed
with 300 ohm twin lead, and tuned with a johnson matchbox. Worked
decent on 40 to 10 meters, but too large for what you need.

73 Merv K9FD/KH6

> Hi,
> No I am presenting a software package and would like to show some
> signals on the K3 indoors at Dayton. So the antenna has to be small.
> Transmit not necessary!
> Thanks
>
> -----Original Message----- From: Merv Schweigert
> Sent: Tuesday, February 10, 2015 11:56 AM
> To: [hidden email]
> Subject: Re: [Elecraft] K3: Indoor antennas at Dayton?
>
> Must be something I am missing here, your going to present at Dayton a
> talk about
> indoor antennas and have no experience using them?
>
> Maybe something lost in the translation I missed.
>
> 73 Merv K9FD/KH6
>> Hi I was wondering if anyone has any experience with indoor antennas?
>> I plan to present at Dayton and would like some hints as to how this
>> works. You can contact me off list please.
>> 73 Tom
>> va2fsq.com
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
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>>
>
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tomb18

Re: K3: Indoor antennas at Dayton?

In reply to this post by tomb18

Thanks for all the suggestions. Should be good enough. I like the whip.
73's Tom

On Feb 10, 2015 12:23 PM, Merv Schweigert <[hidden email]> wrote:

>
> Gotcha Tom, thanks, it did not come through like that.
> Should be a number of guys on here using small indoor antennas,
>
> I used one for several years in 2001 while living in a condo on the beach,
> it was 44 foot of wire taped to the ceiling of the second floor condo, fed
> with 300 ohm twin lead, and tuned with a johnson matchbox. Worked
> decent on 40 to 10 meters, but too large for what you need.
>
> 73 Merv K9FD/KH6
>
> > Hi,
> > No I am presenting a software package and would like to show some
> > signals on the K3 indoors at Dayton. So the antenna has to be small.
> > Transmit not necessary!
> > Thanks
> >
> > -----Original Message----- From: Merv Schweigert
> > Sent: Tuesday, February 10, 2015 11:56 AM
> > To: [hidden email]
> > Subject: Re: [Elecraft] K3: Indoor antennas at Dayton?
> >
> > Must be something I am missing here, your going to present at Dayton a
> > talk about
> > indoor antennas and have no experience using them?
> >
> > Maybe something lost in the translation I missed.
> >
> > 73 Merv K9FD/KH6
> >> Hi I was wondering if anyone has any experience with indoor antennas?
> >> I plan to present at Dayton and would like some hints as to how this
> >> works. You can contact me off list please.
> >> 73 Tom
> >> va2fsq.com
> >> ______________________________________________________________
> >> Elecraft mailing list
> >> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> >> Help: http://mailman.qth.net/mmfaq.htm
> >> Post: mailto:[hidden email]
> >>
> >> This list hosted by: http://www.qsl.net
> >> Please help support this email list: http://www.qsl.net/donate.html
> >> Message delivered to [hidden email]
> >> .
> >>
> >
> > ______________________________________________________________
> > Elecraft mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/elecraft
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: mailto:[hidden email]
> >
> > This list hosted by: http://www.qsl.net
> > Please help support this email list: http://www.qsl.net/donate.html
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> > protection is active.
> > http://www.avast.com
> >
> >
>

w5tvw

Re: K3: Indoor antennas at Dayton?

In reply to this post by Merv Schweigert

I didn't see the intial post. Several years back I used to regularly
work eastern Europe QRP with a Heathkit 5 watter on 20 CW around
0500-0600 GMT. This used a 22' piece of hookup wire tacked in the
corner of the drywall and the ceiling running along the length of the
bedroom and excess thru the bathroom doorway to an attachment point in
bathroom. It was very surprising how much DX I worked every night.
It can be done when conditions are right.

This past fall from Thanksgiving to new years I worked Les W8YCM/6Y5
nearly every day when he was on vacation in Jamaica, several times with
a YAESU FT-817 ND barefoot and a Buddipole dipole 9 feet off the ground.

It can be done with low power and a somewhat compromised antenna when
conditions are limited.

73,

Sandy W5TVW

On 2/10/2015 10:56 AM, Merv Schweigert wrote:

> Must be something I am missing here, your going to present at Dayton a
> talk about
> indoor antennas and have no experience using them?
>
> Maybe something lost in the translation I missed.
>
> 73 Merv K9FD/KH6
>> Hi I was wondering if anyone has any experience with indoor antennas?
>> I plan to present at Dayton and would like some hints as to how this
>> works. You can contact me off list please.
>> 73 Tom
>> va2fsq.com
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>> Message delivered to [hidden email]
>> .
>>
>
> ______________________________________________________________
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Doug Turnbull

Re: K3: Indoor antennas at Dayton?

In reply to this post by tomb18

Tom,
You might find out if signals can be heard within the arena - there
must be a lot of steel in the structure. I think Elecraft uses recorded
signals for their stand's display. Do not hold me to this but the likes or
Eric, Wayne or Don would know for sure.

73 Doug EI2CN

-----Original Message-----
From: Elecraft [mailto:[hidden email]] On Behalf Of Tom
Blahovici
Sent: 10 February 2015 17:38
To: Merv Schweigert
Cc: [hidden email]
Subject: Re: [Elecraft] K3: Indoor antennas at Dayton?

Thanks for all the suggestions. Should be good enough. I like the whip.
73's Tom

On Feb 10, 2015 12:23 PM, Merv Schweigert <[hidden email]> wrote:
>
> Gotcha Tom, thanks, it did not come through like that.
> Should be a number of guys on here using small indoor antennas,
>
> I used one for several years in 2001 while living in a condo on the beach,

> it was 44 foot of wire taped to the ceiling of the second floor condo, fed

> with 300 ohm twin lead, and tuned with a johnson matchbox. Worked
> decent on 40 to 10 meters, but too large for what you need.
>
> 73 Merv K9FD/KH6
>
> > Hi,
> > No I am presenting a software package and would like to show some
> > signals on the K3 indoors at Dayton. So the antenna has to be small.
> > Transmit not necessary!
> > Thanks
> >
> > -----Original Message----- From: Merv Schweigert
> > Sent: Tuesday, February 10, 2015 11:56 AM
> > To: [hidden email]
> > Subject: Re: [Elecraft] K3: Indoor antennas at Dayton?
> >
> > Must be something I am missing here, your going to present at Dayton a
> > talk about
> > indoor antennas and have no experience using them?
> >
> > Maybe something lost in the translation I missed.
> >
> > 73 Merv K9FD/KH6
> >> Hi I was wondering if anyone has any experience with indoor antennas?
> >> I plan to present at Dayton and would like some hints as to how this
> >> works. You can contact me off list please.
> >> 73 Tom
> >> va2fsq.com
> >> ______________________________________________________________
> >> Elecraft mailing list
> >> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> >> Help: http://mailman.qth.net/mmfaq.htm
> >> Post: mailto:[hidden email]
> >>
> >> This list hosted by: http://www.qsl.net
> >> Please help support this email list: http://www.qsl.net/donate.html
> >> Message delivered to [hidden email]
> >> .
> >>
> >
> > ______________________________________________________________
> > Elecraft mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/elecraft
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: mailto:[hidden email]
> >
> > This list hosted by: http://www.qsl.net
> > Please help support this email list: http://www.qsl.net/donate.html
> > Message delivered to [hidden email]
> >
> > ---
> > This email is free from viruses and malware because avast! Antivirus
> > protection is active.
> > http://www.avast.com
> >
> >
>

N3XX

Re: K3: Indoor antennas at Dayton?

In reply to this post by tomb18

Try a dummy load. It should put out a good enough signal if you're receiver
is close.

73,
Tim - N3XX

----- Original Message -----
From: "Tom" <[hidden email]>
To: "Merv Schweigert" <[hidden email]>; <[hidden email]>
Sent: Tuesday, February 10, 2015 12:01 PM
Subject: Re: [Elecraft] K3: Indoor antennas at Dayton?

> Hi,
> No I am presenting a software package and would like to show some signals
> on the K3 indoors at Dayton. So the antenna has to be small. Transmit
> not necessary!
> Thanks
>
> -----Original Message-----
> From: Merv Schweigert
> Sent: Tuesday, February 10, 2015 11:56 AM
> To: [hidden email]
> Subject: Re: [Elecraft] K3: Indoor antennas at Dayton?
>
> Must be something I am missing here, your going to present at Dayton a
> talk about
> indoor antennas and have no experience using them?
>
> Maybe something lost in the translation I missed.
>
> 73 Merv K9FD/KH6
>> Hi I was wondering if anyone has any experience with indoor antennas? I
>> plan to present at Dayton and would like some hints as to how this works.
>> You can contact me off list please.
>> 73 Tom
>> va2fsq.com
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>> Message delivered to [hidden email]
>> .
>>
>
> ______________________________________________________________
> Elecraft mailing list
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> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
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> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]
>
> ---
> This email is free from viruses and malware because avast! Antivirus
> protection is active.
> http://www.avast.com
>
> ______________________________________________________________
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> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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hf4me

Re: K3: Indoor antennas at Dayton?

In reply to this post by tomb18

From my limited experience with trying to receive anything inside commercial
buildings, arenas, VFW halls, etc. it is nearly impossible and certainly
unsatisfactory. I have spent way too much time trying to get a signal that
I could use. For your demo, you might consider bringing a station to
generate and transmit your expected receive data into a dummy load and then
do your demo receiving that data. Good luck, you'll need it to receive.
73, Jim KG0KP

-----Original Message-----
From: Elecraft [mailto:[hidden email]] On Behalf Of Tom
Sent: Tuesday, February 10, 2015 11:02 AM
To: Merv Schweigert; [hidden email]
Subject: Re: [Elecraft] K3: Indoor antennas at Dayton?

Hi,
No I am presenting a software package and would like to show some signals on
the K3 indoors at Dayton. So the antenna has to be small. Transmit not
necessary!
Thanks

-----Original Message-----
From: Merv Schweigert
Sent: Tuesday, February 10, 2015 11:56 AM
To: [hidden email]
Subject: Re: [Elecraft] K3: Indoor antennas at Dayton?

Must be something I am missing here, your going to present at Dayton a talk
about indoor antennas and have no experience using them?

Maybe something lost in the translation I missed.

73 Merv K9FD/KH6
> Hi I was wondering if anyone has any experience with indoor antennas?
> I plan to present at Dayton and would like some hints as to how this
works.

> You can contact me off list please.
> 73 Tom
> va2fsq.com
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net Please help support this email
> list: http://www.qsl.net/donate.html Message delivered to
> [hidden email] .
>

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Jim Brown-10

Re: K3: Indoor antennas at Dayton?

In reply to this post by Doug Turnbull

On Tue,2/10/2015 10:11 AM, Doug Turnbull wrote:
> You might find out if signals can be heard within the arena - there
> must be a lot of steel in the structure.

The far greater issue is likely to be RF noise. Elecraft does, indeed,
use at least some recorded stuff in their display. They also use remote
access to one or more stations, one of which is my neighbor K6XX, an
engineer at Elecraft.

73, Jim K9YC
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wayne burdick

Re: K3: Indoor antennas at Dayton?

Administrator

In reply to this post by Doug Turnbull

The building is steel and almost impervious to RF. We had an external antenna last year.

You can do a demo using "inside signals," but they won't be very interesting unless you plant stooges around the arena with QRP rigs.

Wayne
N6KR

On Feb 10, 2015, at 10:11 AM, Doug Turnbull <[hidden email]> wrote:

> Tom,
> You might find out if signals can be heard within the arena - there
> must be a lot of steel in the structure. I think Elecraft uses recorded
> signals for their stand's display. Do not hold me to this but the likes or
> Eric, Wayne or Don would know for sure.
>
> 73 Doug EI2CN

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Doug Turnbull

Re: K3: Indoor antennas at Dayton?

Wayne and All,
This sets Elecraft apart. The principals of the company and design
engineers talk with their customers. How wonderful.

73 Doug EI2CN

-----Original Message-----
From: Wayne Burdick [mailto:[hidden email]]
Sent: 10 February 2015 18:52
To: Doug Turnbull
Cc: 'Tom Blahovici'; 'Merv Schweigert'; [hidden email]
Subject: Re: [Elecraft] K3: Indoor antennas at Dayton?

The building is steel and almost impervious to RF. We had an external
antenna last year.

You can do a demo using "inside signals," but they won't be very interesting
unless you plant stooges around the arena with QRP rigs.

Wayne
N6KR

On Feb 10, 2015, at 10:11 AM, Doug Turnbull <[hidden email]> wrote:

> Tom,
> You might find out if signals can be heard within the arena - there
> must be a lot of steel in the structure. I think Elecraft uses recorded
> signals for their stand's display. Do not hold me to this but the likes
or
> Eric, Wayne or Don would know for sure.
>
> 73 Doug EI2CN

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kevinr@coho.net

Re: K3: Indoor antennas at Dayton?

In reply to this post by wayne burdick

I was an Elecraft representative at Seapac in 2002 or 2003. I hooked
the K2 up to the metal framing holding the venue's curtains. There were
two pedestrian mobile stations to work and by the end of the day two
more fixed stations. So we were able to make contacts with each of
them. I brought some special QSL cards for the occasion and talked with
quite a few CW operators. The sound of CW brought many folks to the
Elecraft booth. It was fun to watch them copy in their heads as they
listened.

Load whatever you can and have fun.
73,
Kevin. KD5ONS

On 2/10/2015 10:52 AM, Wayne Burdick wrote:

> The building is steel and almost impervious to RF. We had an external antenna last year.
>
> You can do a demo using "inside signals," but they won't be very interesting unless you plant stooges around the arena with QRP rigs.
>
> Wayne
> N6KR
>
> On Feb 10, 2015, at 10:11 AM, Doug Turnbull <[hidden email]> wrote:
>
>> Tom,
>> You might find out if signals can be heard within the arena - there
>> must be a lot of steel in the structure. I think Elecraft uses recorded
>> signals for their stand's display. Do not hold me to this but the likes or
>> Eric, Wayne or Don would know for sure.
>>
>> 73 Doug EI2CN
>
>
> ______________________________________________________________
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Gary Smith-2

Re: K3: Indoor antennas at Dayton?

In reply to this post by Doug Turnbull

In the early 90's I lived in a condo and couldn't put anything
outside for an antenna. The MFJ Isoloop was fairly new but I wanted
to work the lower bands more than 10-20.

In either the ARRL Handbook or the antenna handbook from the 80's
(Don't think it was Bill Orr's handbook) I found instructions written
by a Ham in Florida I believe, to make an octagonal short
transmitting loop out of 1" copper pipe and 45° junctions. An
extremely high Q antenna, it was center fed at the bottom horizontal
pipe with a gamma match made of flexible copper tubing running from
the center of the coax to the center of the first 45° section. It had
a very narrow bandwidth of maybe 5KHz but it was a perfect 1:1 match
at its resonant frequency.

You could adjust the resonant frequency by changing capacitance at
the feed point. There were several ways of doing this, the most
straightforward way was to use air variables that were wide enough
not to arc. I wanted to use my SB-220 with this antenna so I decided
to use an on-hand 15KV 5-500 pF vacuum variable. I wanted to make a
geared stepper motor control to run it remotely but that was new
technology to me at the time and opted instead to use a pair of
servos which worked perfectly. I put a Groth tuner on the servo in
the control box by the radio and kept the numbers to get tuned
quickly in a notebook.

I made three of these antennas and placed them on the wall going east
west with the largest octagon 7 feet from top to bottom, a smaller
one about 4.5 feet high inside and inside of that, another one 3 feet
high. Using all three of these antennas I could cover 160 through 10.
According to the literature at its resonant frequency it was
extremely efficient approaching something like 95% to that of a
dipole at the same height(I never compared one of these antennas to a
dipole at the same height but I will say it worked wonderfully for an
indoor antenna). I built small shelves to hold the vacuum variable
and servo assembly and used quick disconnects to allow me to switch
between antennas without unscrewing anything, just relocating and
reattaching that assembly.

The XYL was willing to let me run the coax and control cable from the
basement to the second floor of the condo where we had an unused
spare room. I never had any arcing issues of any kind using the
vacuum variable with that Heathkit amplifier. Since I was not in the
room and didn't want her to touch the antenna while I was
transmitting, she understood the reason not to go near the antenna
and as an extra precaution, when the servo was engaged, an attached
lightbulb was lit to resolve all doubt.

It would be difficult to use such an antenna to chase DX that
operates split because the band with is not as wide as some of the
splits I'm seeing today. There were some crossover frequencies
between the different antennas where the Q was lower at the bottom
end of a larger loop and that would allow much larger splits. It was
interesting to tune the antenna because you would turn to the desired
frequency and then adjust the capacitor to get there and it was dead
silent in the headphones until it was resonant where you were
listening and instantly the band would become alive and loud.
Extremely steep skirts.

One of the most attractive aspects to me was that it would provide a
good vertical polarization from your signal and that made it a good
choice for DX. When I look through my log at the DX I was able to
work with those antennas,
I'm surprised at the number of entries.

73,

Gary
KA1J

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