Most Popular Articles
Variation on the Shielded-Loop AM Antenna
Greg Manfroi of WIUM/WIUW, Western Illinois University, Macomb, IL,
sent us this idea on a construction method for the shielded-loop AM
Start with the electrical specifications as described in the companion article. Once the loop is built, it must be supported in a ring to yield the best results. One way of doing this is to create a loop of PVC pipe. This will result in a square if 90-degree elbows are used or an octagon if 135-degree elbows are used. Cutting the pipe and assembling the loop can be time consuming. Instead of PVC, Greg substituted a material that is sturdy, almost perfectly round, and in most cases, easily found in any toy store or discount department store. Greg’s idea was to use a hula hoop, which are available in large and small sizes. The small size is just right. Some hoops have a seam that can be easily opened, but if not, cut a hole so the "magic hula beans" (as Greg calls them) can be removed. The wire is fed through the hollow hoop.
A common hula hoop is a readily available item that can be used to house a home-made shielded-loop AM antenna.
For the connector, Greg opened a 75-ohm cable splitter and drilled
out the dual-port side. The wire connections were made inside the
splitter shell. The shell was reassembled and then attached to the hoop
with a silicone sealant.
A standard splitter makes a convenient connector and wire-termination housing.
Greg reports that only drawback to using a hula hoop is that they
come florescent colors that are typically not associated with
industrial-use applications. Greg was able to find a shade of blue that
was not too objectionable.
The result is a shielded-loop AM antenna in a perfect circle with a built-in F connector. His cost of parts was less than $3.00 for the hula hoop. He already had the wire and splitter.
Acceptable Use Policy blog comments powered by Disqus
[an error occurred while processing this directive]
Today in Radio History
The history of radio broadcasting extends beyond the work of a few famous inventors.
EAS Information More on EAS
The feed provides feeds for all US states and territories.
Need a calendar for your computer desktop? Use one of ours.
Information from manufacturers and associations about industry news, products, technology and business announcements.
Browse Back Issues[an error occurred while processing this directive]
Also in the December Issue
- Local Radio Spotlight: Koser Radio Group
- Trends in Technology: Streaming Audio Update
- Contest Rules Rewrite and EAS Issues
- Embedded Computing, With a Side of Pi
- Field Report: TASCAM US-366