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Old September 6th 06, 02:24 AM posted to rec.antiques.radio+phono,rec.radio.amateur.boatanchors,rec.radio.amateur.antenna,rec.radio.amateur.homebrew
Robert Sherrod Robert Sherrod is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 9
Default Curious about the I.R.E. Standard Dummy Antenna



H. P. Friedrichs wrote:
I am interested in the origins and purpose of the "IRE (Institute of
Radio Engineers) Standard Dummy Antenna," as used during the alignment
of radio receivers.

I first came across this circuit in some old Hallicrafter's
documentation, which described the alignment of a particular radio. The
"IRE Standard Dummy Antenna" consists of four components--- a 200pf cap
in series with a 20 uH inductor, which links the signal generator to the
receiver's antenna input. A 400 pF cap in series with a 400 ohm resistor
is connected in parallel with (shunts)the inductor.

I gather that this circuit models a wire antenna of some type. Is this
true? What is the import of the component values and how were they
arrived at? I modeled the circuit in Spice and graphed the transfer and
impedance curves but it is not entirely clear to me what benefit there
is to using this circuit.

I've also Googled this and found some references here and there, but
nothing explains the "why" of it.

Is there anyone who can shed light on this?

73
Pete
AC7ZL

hpf (at) gainbroadband (dot) com


I built an I.R.E. dummy antenna recently to perform an alignment on a
Hallicrafters S-120. It is cobbled together on a small perfboard with
copper lands around the holes, has a length of coax with a male BNC
connector to go the the sig-gen and a female BNC connector to attach the
sig-gen lead.

I will post a pic on a.b.p.r when I can.

Bobby
KC9IHK