[Antennaware] From CO8LY

Steve Harrison k0xp at dandy.net
Mon Jun 25 10:57:40 EDT 2007

At 05:46 AM 6/25/2007 +0000, Steve Harrison wrote:
>>Each resistance is the 22ohn and they are very difficult of finding them.
>>Is there some other solution to use other resistances or??????????.
>>I wait urgent answer of you, thank you in advance.
>Yes, you can use a different resistance.

I should have been clearer what you can use. Any resistance from maybe as
low as 10 ohms to as high as 100 ohms has been used. However, the lower the
resistance, the more RF power the resistors will pass and the hotter they
may become. The higher the resistance, the less effective they will be at
reducing the Q of the coils of the parasitic suppressors and the more
likely that the suppressors will be ineffective. In addition, the higher
the resistance, the more that the coils, theirselves, will act as part of
the 6 meter tank circuit inductance.

The usual resistor value is 47, 51, or 56 ohms, which are common 2 watt
carbon composition resistor values. You may also combine resistors in
parallel; for example, four 220 ohm, 1 watt types; or 3 150 ohm types. You
should aim for as much power rating of the resistor as possible up to maybe
10 watts; beyond that, the resistor package becomes large and unwieldy to
handle. If you have to use resistors in parallel, so that a coil of wire
cannot be wound around them, then make the coil of a U-shaped piece of
heavy wire, each end connected to the ends of the resistors. This U-shape
probably should not be longer than 2, and certainly not more than 3, inches
long from one end of the wire to the other.

If you do make a new suppressor like above, and find the new resistors
overheating, then reduce the length of wire in the coil or U-shape. Cut it
shorter then try again.

Steve, K0XP

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