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How to add external AM/FM antenna to a radio

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aldg

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Feb 12, 2011, 2:21:23 AM2/12/11
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I have a Craig CR-4100 radio at my desk at work. It's surrounded by a
metal shelf work on the desk top. As a result, it picks up only 1 or 2
FM stations and no AM stations.

The radio's built-in antennas are:

1. Internal bakelite AM antenna with NO external antenna input plug;
and an

2. External (on back of radio) extending metal pole FM antenna with NO
external antenna input plug.

I would like to add an active or passive external AM and FM antenna
that I can set on the top of the desk's metal shelf work and allow the
radio to pull in all the local AM and FM stations.

From the Usenet Newsgroup: rec.radio.shortwave, I would like the
following:

1. A suggestion for an external AM and FM active or passive antenna;
and

2. A wiring diagram that will describe how to install the external
antenna.

Thanks, in advance for your input in this matter.

Al Gershen
Grants Pass, OR, USA

Brenda Ann

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Feb 12, 2011, 4:51:51 AM2/12/11
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"aldg" wrote in message
news:d9e57b0f-4689-40a0...@j9g2000prj.googlegroups.com...


--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

Adding external antenna connections to most any radio is fairly simple, but
there may be diminishing returns.

For AM, it's as simple as making about 5-8 loops of small gauge wire around
the end of the loopstick (these are not bakelite, but ferrite.) You should
ground one end of the loops to chassis ground, then bring connections to the
back of the radio on whatever type of connection you like or will fit.

For FM, even easier. Bring a wire from chassis ground and a wire from the
internal connection for the whip to the back of the radio as with the AM
antenna.

Note: if you get NO AM now, it's not likely to help adding an antenna.
Alternately, you can use an external loop for AM (Terk has some good ones),
but again, if you get no AM now.... Grass Pants isn't much of a hot spot of
radio DX... :) All I ever got was the local station and KMED going through
there (except at night, of course).

RHF

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Feb 12, 2011, 5:46:14 AM2/12/11
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1 - Place another AM/FM Radio next to an outside
facing Window where you can get good AM & FM
Radio Reception. Connect an FM Transmitter to
that Radio. Tune-in the Window Radio to the AM
or FM Station you want to Listen to. Use your Deck
Top Radio to Tune-in to the FM Wireless Transmitter.
When you want to change AM & FM Stations re-tune
the Window Radio -note- That the Deck Top Radio
is always Tune-in to the same FM Wireless Transmitter
Frequency.

* FM Wireless Transmitter
http://www.wholehousefmtransmitter.com/
.
2 - If you have WiFi in your Office/Home buy a WiFi
Radio and Listen to Streaming Audio via the Internet.

* WiFi Radio
http://www.ccrane.com/radios/wifi-radios/

* What Is WiFi Internet Radio ?
http://www.ccrane.com/radios/wifi-radios/what-is-wifi.aspx
-or-
http://www.google.com/search?q=WiFi+Radio

IMHO both 1 and 2 may be more productive use
of your time and money : Then trying to Add an
External Antenna to a Radio that is surrounded
by Metal {Shielding} - iane ~ RHF
.
.

Wimpie

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Feb 12, 2011, 11:41:41 AM2/12/11
to

Hello,

For the wiring diagram and instructions, see Brenda Ann's excellent
response.

Regarding diminishing returns, relocate your receiver (or other
receiver) to a place where you can receive the stations you want (both
FM and AM), and that is appropriate to locate your antennas. When you
can find such a place, you can proceed adding the external antenna
inputs.

If you plan to install the antennas outdoor (that means cable will
enter the building from outside), make sure to follow local
regulations on safety (lightning).

For the FM antenna, a straight wire half wave dipole or folded dipole
(with 4:1 balun in it) will be fine if you can receive the stations on
a portable also (at the position of the antenna). Use 75 or 50 Ohms
cable to connect the antenna to your receiver.

For the AM antenna, a large single wire loop (about 1 square meter [11
square feet] may do the job. Also here, use 75 or 75 Ohms cable to
connect the antenna to the receiver. The loop must be oriented
vertically and has maximum reception in the plane of the loop.

If you are in an interference rich environment, you may need to insert
a balun (if not already present in the antennas), to reduce the effect
of interference generated close to the cables and receiver.

Note that antennas exist that may perform better, but complexity
increases more then proportional and success depends on several other
factors. I don't know the quality of the receiver, but using external
antennas may result in bad reception due to strong signal overload.

Best regards,


Wim
PA3DJS
www.tetech.nl
without abc, PM will reach me.

illno...@gmail.com

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Nov 10, 2017, 3:59:59 PM11/10/17
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I have a loop antenna from an home system and want to wire it to a boombox any thoughts?

george.sperle...@gmail.com

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Mar 4, 2018, 9:47:16 AM3/4/18
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allise...@gmail.com

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Mar 6, 2018, 3:12:24 PM3/6/18
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Stick a wire on your cell phone and wrap the wire around your radio. It might work.

George Cornelius

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Mar 7, 2018, 7:26:19 AM3/7/18
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In article <37686404-1de7-4ee4...@googlegroups.com>, illno...@gmail.com writes:
= I have a loop antenna from an home system and want to wire it to a boombox any thoughts?
In article <05c82d14-523a-4000...@googlegroups.com>, allise...@gmail.com writes:
> Stick a wire on your cell phone and wrap the wire around your radio. It might work.

Except it might block (or worse) at the RF input every time the cell phone
went into transmit mode to check in with the tower. And don't even try
to _talk_ on that phone.

Still likely a better idea than thinking a loop antenna works for both
AM and FM.

Larry's right, though. Get a real AM antenna and try magnetic coupling
by wrapping a loop around the case. Or build yourself a loop large
enough to completely enclose your (plastic) boombox and see if it will
self-couple. Maybe mount it on a rotating vertical axis - antenna and
all on a lazy Susan, the radio elevated, possibly on blocks, above the
lower part of the loop.

FM's different. Some cheap systems use the cord as an FM antenna, some
have whip antennas. Try a random length of wire taped to the power cord,
or to the whip, for a few inches. Better yet: get a decent boombox with
an FM input and get a real FM antenna.

George

allise...@gmail.com

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Mar 7, 2018, 9:57:54 AM3/7/18
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www.abc-lounge.com/fr ...See how easy that is.

phil...@gmail.com

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Aug 4, 2020, 7:03:02 PM8/4/20
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On Wednesday, 7 March 2018 07:26:19 UTC-5, George Cornelius wrote:
> Better yet: get a decent boombox with
> an FM input and get a real FM antenna.
>
> George

Can you name a SINGLE FM boombox with CD player currently on the market that has an FM antenna jack? I've only found one, and it has a TV on the front and is some Chinese brand I've never heard of (JWIN).
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