It what was probably the easiest AM-DX loopstick transplant ever
performed, a 7" loopstick from a Channel Master Super Fringe (model
6515) was soldered into an E100, resulting in greatly improved
sensitivity (and apparently maintaining great selectivity).
For a variety of reasons, this transplant is extremely easy to
accomplish, even for those who feel intimidated by a soldering iron.
There are only two connections to the stock loopstick, both easily
accessible on the back circuit board. The stock loopstick is removed
very easily with an exacto knife, or even a flat screwdriver.
If you are lucky enough to get a Channel Master Super Fringe
model 6515 off of eBay (one went for $8 this morning), you don't even
need an LCR meter to do the transplant. The stock coil has an
inductance of .297mh, almost the same as the Channel Master long
coil, on the 7" ferrite bar. Simply solder in the Channel Master
long coil on the 7" loopstick, and peak it on a 600 kHz signal, as
described in John Bryant's E100 alignment file.
The 7" loopstick E100 "smokes" a stock unit in DXing, and
provides stiff competition for the 6.25" Sangean DT-200VX model. It
will shortly receive a couple more 7" blank bars, to face the
ultimate RF overload test. If its superior selectivity holds up, it
may well be the great combination of Ultralight sensitivity and
selectivity that we DXpeditioners have been looking for.
73, Gary DeBock