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Old June 10th 06, 02:48 AM posted to rec.radio.shortwave
RHF
 
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Default Cambridge SoundWorks # 740 Radio - Loop Antenna Up-Sizing ?

Telamon,

I have tried building and using a larger Un-Tuned Loop Antenna
with the Cambridge SoundWorks # 740 Radio several times
with out any sucess.

ORIGINAL AM/MW LOOP ANTENNA :
Eight Turns (8T) of Wire on a 4 5/8 Inch Square Form
with a 51 Inch Twisted Pair of Wires to the AM/MW
Antenna Input Jack. - - - Should be about 17.3 uH

AM/MW Loop Antenna Calculator :
http://www.mindspring.com/~loop_ante...loop_calc4.htm
This original (OEM) Loop Antenna worked barely OK
with the Radio for local AM/MW Radios Stations only.

LARGER AM?MW LOOP ANTENNA :
Four Turns (4T) of Wire on a 14 Inch Square Form
with a 15 Feet Twisted Pair of Wires to the AM/MW
Antenna Input Jack. - - - Should be about 17.5 uH
This Larger AM/MW Loop Antenna did not work at all.

Tried a 51 Inch Twist Pair feed-in-line and a 72 Inch
Coax Cable feed-in-line with this Larger Loop Antenna
with worse results then the original Loop Antenna.

-IF- In fact the Radio is Tuning the Loop then this Larger
AM/MW Loop Antenna should have worked at 17.5 uH
with the Radio's internal circuitry. It Did Not.

still insearch of . . . ~ RHF