When I was first into ham radio, I was just a kid and had practically no
money.
Most of the guys I knew, including me, used a light bulb as a dummy.
We couldn't afford a real dummy. (The Heathkit Cantenna later changed
that.)
The wattage was very easy; although we rated our transmitters in "Input
Power", we guestimated the output power (say, 60%...depending on the class
of the amplifier) and then chose a light bulb just slightly larger.
If we had a rig rated 100w, we used a 60w or 75w light bulb.
When lit, it quickly approached 50 Ohms.
The trouble is, it was not 50 Ohms when unlit and cold, so the load varied.
Not a problem with a continuous carrier or AM.
It was not a very good dummy load for SSB, where the power level is changing
all the time.
Especially with today's SSB rigs which don't like more than 3:1 SWR, you
might have problems.
I would not do that today.
Although we considered it a dummy, I have made many QSOs with my lightbulb
dummy.
73
Rick
-----Original Message-----
From: tentec-bounces@contesting.com [mailto:tentec-bounces@contesting.com]
On Behalf Of Jim WA9YSD
Sent: Friday, December 10, 2010 2:45 PM
To: tentec@contesting.com
Subject: Re: [TenTec] was OT: Indoor Antenna: re B&W type terminated dipoles
Many station have been worked by various people using a light bulb for a
dummy
load. I had seen it some where back in the day in a magazine or book that
some
one worked out what wattage light bulb wish I could find that one.
Stay on course, fight a good fight, and keep the faith. Jim K9TF/WA9YSD
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