I've had problems blowing the resistors due to local (not direct) lightning
strikes. While picking up the driveway one day I found a pencil that had
been run over. The wood had split, leaving a perfect graphite rod. A thought
occurred and I measured the resistance. Wound fine copper wire at each end
of the desired resistance and packaged several together in a weatherproof
package. They've been in service for over a year with no problems.
Ron, KA9ALC
----- Original Message -----
From: "Brad Rehm" <bradrehm@texas.net>
To: "Clive GM3POI" <gm3poi@btinternet.com>; <towertalk@contesting.com>
Sent: February 10, 2002 17:29
Subject: Re: [TowerTalk] Beverage Termination
>
>
> "Has anyone got any views on the suitability or not of using metal film
> resistors to Terminate Beverages."
>
> Clive,
>
> I wouldn't use metal film resistors for all the reasons which have been
> given. Carbon resistors are getting hard to find, and although I've got a
> small collection, I looked for something better. Found the non-inductive
> chip resistors that are available in a TO-220 transistor package. They're
> rated at fairly high instantaneous currents, and they can dissipate up to
35
> Watts when properly heat-sinked. Dielectric strength is 1800 Volts, and
> their maximum operating voltage is 350 Volts. Cost in the U.S. is about
> $3.00. Noise on the beverages is as low as ever, and I've had no resistor
> failures in 3 years of service.
>
> These are made by Ohmite (the TCH35P series), and I've bought them through
> Mouser Electronics.
>
> 73,
> Brad, KV5V
>
>
>
> ________________________________________________________________________
> Where do you get ICE bandpass filters & beverage matching boxes? The
> same place that pays for the hosting of this list: The eHam Store.
> Order online at http://store.eham.net.
> -----------------------------------------------------------------------
>
> -----
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>
________________________________________________________________________
Where do you get ICE bandpass filters & beverage matching boxes? The
same place that pays for the hosting of this list: The eHam Store.
Order online at http://store.eham.net.
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