Bologna - Italy, Sept 12 -2002
To N6WG, Bob and all TOPBAND List
Object: 50 Ohm to 900 Ohm transformer with Amidon Ferrite Toroidal Core
FT140-43 for Flag, pennant, delta-ewe, as pointed out from
Earl K6SE.
Primary 50 Ohm low impedence side is 8 turns and secondary is 34 turns with
about 990 microH to 1 milliH with a 20 AWG enamelled wire
on an Amidon FT-140-43 imported from Amidon.
Ros check with a new MFJ269B Analyser showed better ROS match a bit lower in
frequency than 1.8 Mhz.
Insertion loss test I performed a while ago so I do not remember but maybe
close to around 2 dB.
Measurements of two of them back to back to get 50 Ohm to 50 Ohm is better
performed with same lot ferrite selection.
FT-140-43 mechanical data can be found at Amidon Web site:
http://www.amidon-inductive.com/associates_prod_toroidal.htm
Best greatings. 73 de Sergio,
IK4AUY
Also IR4B in contest
Also AC7PC
One of official op. at IY4FGM, Marconi Memorial Station
My personal WEB Site: http://www.qsl.net/ik4auy/
e-mail: ik4auy@arrl.net
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