ANTENTOP- 01- 2016 # 020

Experimenters with Non Snap Ferrite Cylinder Bead RF Chokes

Third experimental transformer was made with three Cylinder Ferrite RF Chokes. Figure 8 shows schematic of the transformer. It was classical RF Transformer where one turn is primary and second turn is the secondary winding. Then the transformer was tested. Primary winding was connected to MFJ- 259B. Secondary winding was loaded on to 51- Ohm resistor. Figure 9 shows the transformer loaded to 51-Ohm resistor. Table 3 shows data obtained for the three Ferrite RF Chokes transformer.

As you can see from the table the transformer had parameters better the one and two cylinder transformer. Certainly the transformer may be used for receiving purposes. I tested the transformer with my transceiver IC- 718 and receiver Hallicrafters S- 85. Transformer worked good up to 160- meter Band. As well the transformer performed well at MW band. Transformer was tested with IC-718 in transmitting mode, 15- wt. SWR showed by IC- 718 is close to SWR showed by MFJ- 259B.

Figure 9 RF Transformer on Three Cylinder Ferrite RF Chokes loaded to 51- Ohm Resistor

Conclusion: The transformer may be used as Insulated Transformer for Receiver at the HF and MW. The transformer may be used for some purposes (like insulation transformer installed on antenna and then matched with coaxial cable) at transmission mode at the 80- 10 meter Bands.

Figure 8 RF Schematic for RF Transformer Made on Three Cylinder Ferrite RF Chokes

Table 3 Three Cylinder Ferrite RF Chokes loaded to 51- Ohm Resistor. Data obtained with MFJ- 259B and IC-718

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