For a loading coil of j200 ohms at 500 MHz you need an inductance of 0.057
uH.

Wind 4 complete turns of 16 awg wire on a former 5.6 mm diameter, 10 mm
long. Q will be around 600.

For the above little calculation and many others use program SOLNOID3.
Download in a few seconds from website below and run immediately.
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Regards from Reg, G4FGQ
For Free Radio Design Software go to
http://www.btinternet.com/~g4fgq.regp
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