In article ,
Jeff Liebermann wrote:

It is just a simple old screw, made for a copper wire antenna, the radio
was made in the late 50's. I used to have one that I made out of a
variable capacitor and just tuned the knob to trim the antenna. I am now
64 and that was when I was in junior high school? Can I get a variable
capacitor for an old radio and connect the two ends?

I'm 67 and know the feeling. The lab that I patiently built up over
the last 40 years is now considered a test equipment museum.

Yes. Just a small 365pf(??) or lower value variable capacitor should
work. I wanted to see the circuitry so I could provide a better guess
at the capacitor value. Something like these:
http://www.ebay.com/sch/i.html?_nkw=365+pf+variable
Any old tube or xsistor radio should have one. Dig around at thrift
shops or ham flea markets for old radios and junk boxes.

Good luck and I'm amazed that such an old radio still works.

There's a manual and schematic for the HE-10 (apparently a
Globe-Trotter 9R-4J) at the BAMA.EDEBRIS.COM site.

It looks as if you can use either an unbalanced random-wire or zep
antenna (connect to A1, jumper A2 to E, and connect E to a good
ground), or a balanced doublet (remove the jumper, connect antenna to
A1 and A2).

In either case, A1 and A2 feed into the front-end preselector, which
has a 2P4T switch (one position per band) connected to four sets of
tuned transformer couplers. The signal goes into the primary of one
transformer, out through the (tuned-per-band?) secondary, and then
goes to the grid of the first tube via a 250 pF cap. One of the
tuning-capacitor gangs is connected to the secondary/gate feed as
well.