(de W8JI) --
> The only things hurting a Beverage besides catastrophic
> construction errors or bad components are:
>
_______
Bad components are quite common, based on my personal experience helping a
number of hams get their Beverages working. Here are the ones I've seen:
* Using wirewound resistors, or rather, "lossy inductors"
* Wrong value resistors -- faded color code (red looks like brown on the
third band), misinformation on the choice of resistance, or just a bad
resistor out of the junk box.
The remedy is simple -- use new 2-watt carbon, ceramic composition, or other
robust, non-inductive resistors. Rule-of -thumb for value is 560 ohms for a
high (8-foot) Beverage, down to maybe 270 or 330 ohms for a very low or
on-ground Beverage.
* The most common problem is bad homebrewed transformers. Mostly, these are
due to the wrong core (hamfest bargains, gift from another ham, or "what was
in my junk box"), and sometimes inexperienced builders don't get the
windings right. Also, there appear to be some published designs that are
extremely lossy.
The remedy is to use a foolproof design -- The binocular core types are as
close to this as you can get, and they work as well or better than
toroid-wound transformers.
73, Gary
K9AY
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