This is a unique 1:1 transmission line transformer intended to provide highest possible isolation between input and output. Consequently there is no direct electrical connection between the input and output with all RF energy being conducted through the massive iron powder core. This makes the FCP antenna very quiet while also providing the required inductance for matching to the folded counterpoise. This transformer is intended for use only with the FCP antenna design.
Specifications meet the K2AV FCP Isolation Transformer requirements used with his Folded Counterpoise for 160 or 80 meters.
Use this link for additional construction information.
I recently asked Guy (K2AV) the designer of the FCP if he would tell me what the best lengths for the Inverted L portion of the antenna should be. His response is available here for download and is extremely informative.
|Core Material|| Large 3" DOUBLE HEIGHT iron powder toroid for excellent low frequency performance.
Core is coated and sealed for long term durability.
|Winding Type|| Single bifilar wire pair wound as 1:1 transformer/isolation balun.
|Winding Material|| Heavy gauge polyamideimide Allex 240 Winding Wire.
Windings are inserted into Teflon tubes increasing total breakdown to 10,000 volts.
|Power Rating|| 1.8 - 2.0 MHz or 3.5 - 4.0 MHz - 2kW
All ratings based on resonant load. High SWR will reduce power handling ability.
|Useable Frequency||Band specific - Complete coverage for 160m or 80m depending on unit.|
|Insertion Loss||Less than 1/10th of 1db|
|Connectors|| SO-239 connectors are gold center conductor with Teflon insulation.
Studs and eyebolts are 1/4 inch.
Alternate connectors and Mounting Options are available in the Accessories section.
|Hardware||All Stainless Steel|
|Enclosure Type|| NEMA rated 4x marine grade junction box for outdoor installations.
Cover utilizes integral neoprene gasket for weatherproof integrity.
|Dimensions||4x4x2 inches for main body of unit|
|Additional Info|| Very high efficiency (98-99%).
Iron powder core is very tolerant of high temperatures.