Topband: Preferred Choke Baluns

[Charles Moizeau]

I'd be grateful to learn the preferences of users of these devices.

My set-up is 50-Ohm, 0.405" diameter (Wireman X-4XL) coaxial cable, underground, but within electrical pvc conduit.  This attaches through a PL-259 to a DX Engineering radial attachment plate.  The antenna is an inverted L with its base fed just through a variable capacitor (set for my antenna at ~ 255 pF) .

I have given thought to chopping the PL-259, stringing a bunch of Palomar's ferrite beads on the coax and then re-attaching the PL-259.  

However, an alternative would be to insert a manufactured or home-brewed balun, toroidal or solenoidal, between the radial attachment plate's SO-239 connector and the variable capacitor.

Physical space is not a problem because I've discovered that the DXE radial attachment plate will fit nicely into a 12" x  12" x  6" heavy-duty gray pvc electrical box ($33 at Lowes).  I plan to revise the existing and quite messy above-ground set-up so that the radials will be inserted into the box through tight-fitting and caulked notched holes in the four top edges, just below where its cover will fasten, with their solder lugs attached to the plate 180 degrees opposite from the conventional configuration.  In this way the whole business can be buttoned up tightly and buried, with just the antenna's attachment point and the capacitor's adjustment shaft sticking up.  Perhaps this plan will be inspirational to others.

I'd prefer to see any choke balun recommendations posted to this list rather than sent directly, so as to share the "wealth". 

Tnx es 73,

Charles, W2SH