[comp.dcom.telecom] Modified Plantronics LiteSet Works Great!

tad@ssc.UUCP (Tad Cook) (09/18/89)

I got one of the LiteSets last week from DAK.  My boss got one
a couple of months ago.

Being a ham, I could not resist modifying it.  I noticed that when my
boss got more than 100 ft from the base, he started to fade.  Probably
wasn't helped by all the RFI radiating computers we have around the
office.

I saw the the little antenna on the base was about 1/10 wavelength long,
so I decided to make a 1/4 wave groundplane out of hookup wire.

I popped open the unit and found the ground connection on the circuit
board was common with the ground on the negative power input.  I ran
out a piece of wire for the ground connection.  I also saw that because
of the short antenna, they had loaded it with an inductor.  I disconnected
the antenna, and ran my own wire to the outside of the unit, tapping off
the coil just a few turns from the transmitter.

I put the base unit on a couple of large metal file cabinets next to my
desk, and ran my new 1/4 wave (5 foot) antenna wire up the wall.  I used
wire that matched the wall, so it doesnt look too ugly.  Then I ran 2
ground radials, one in each direction, taped horizontally on the wall,
and hooked these to the ground wire I brought out of the unit.  Then I
ran 2 more 5 foot radials, diagonally from the common ground point across the
filing cabinets, under potted plants, and down opposite corners of the cabinets
to take care of the excess wire.

The range on this thing is now phenomenol.  My boss and I ran a tesst
where I went outside and just kept walking...wonderful clear transmission.

At one point after lunch I took a little hike into the woods north of
our office, found a nice grassy area where I could lay down and watch
the clouds roll by, and took a few calls from customers!

I also got in the car and drove, and found that we still had good
transmission several blocks away!  This was after I got out of the
METAL car, of course.

Tad Cook
tad@ssc.UUCP
KT7H @ N7HFZ
MCI Mail: 3288544