Wirewound resistors are not robust for high energy surges such as lightning
induced current. The 'non-inductive' wirewound resistors are not good for
high voltage surges due to the contra-winding of the wire back over itself.
Carbon composition resistors are popular for high energy and high voltage
because the resistive element has considerable thermal mass. The 2W
resistors can take a 20 joule pulse and survive. They can take a 30 kV pulse
and survive.
Digikey no longer stocks the 2W carbon comps. They do have the 1W type for
$2.03. They do stock the Ohmite OY series of ceramic resistors that
are rated for a 20 kV pulse and and 70 joules. These are $1.19. I would use
these.
Dave WX7G
On Sat, Sep 26, 2009 at 8:44 PM, Gary K9GS <garyk9gs@wi.rr.com> wrote:
> Hello Steve,
>
> How about the WH series from Ohmite? Here's the link to the Digikey page:
>
> http://dkc3.digikey.com/PDF/B092/P1934.pdf
>
> 2W available, $0.88 ea in single piece quantities, inductance <1nH @ 1 MHz
>
> I've never used them but they should work. Anyone else try them?
>
>
> 73,
>
> Gary K9GS
> ++++++++++++++++++++++++++++++++++++++++++++++++
> K9GS
> Gary Schwartz email: k9gs (at) arrl.net
> Check out K9NS on the web: http://www.k9ns.com
> Society of Midwest Contesters (SMC) http://www.w9smc.com/
> GMDXA http://www.eng.mu.edu/gmdxa/
> ++++++++++++++++++++++++++++++++++++++++++++++++
>
> ----- Original Message -----
> From: "Steve Miller" <hsmiller@awsllc.net>
> To: <topband@contesting.com>
> Sent: Saturday, September 26, 2009 1:23 PM
> Subject: Topband: Terminating Resistors
>
>
> > Can someone provide the name of a supplier of 2 watt carbon resistors to
> > be used as terminating resistors on a Beverage antenna? I've found
> > them for $3+ a piece and am looking for a more affordable supplier....or
> > is that the going price??
> >
> > Also, is it absolutely necessary to use carbon resistors? There are
> > other 2 watt resistors that are in my price range!! hi Thanks, 73
> > Steve N0SM
> >
> > _______________________________________________
> > Topband mailing list
> > Topband@contesting.com
> > http://lists.contesting.com/mailman/listinfo/topband
> >
> _______________________________________________
> Topband mailing list
> Topband@contesting.com
> http://lists.contesting.com/mailman/listinfo/topband
>
_______________________________________________
Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband
|