[Elecraft] Fw: Fw: Don't have a 50W dummy load

[Eric Swartz - WA6HHQ, Elecraft]

Hi bob - Your post was far from stupid. On this reflector we welcome all 
questions of this type. Please feel free to post as ask as needed. You will 
certainly get a lot of responses, some closer to the mark than others. At least 
one will be exactly what you are looking for.

We certainly have an verbose group though! I never expected to see so many dummy 
load emails in my inbox..

So let's close this thread at this time inthe interest of keeping list volume 
under control.

73,
Eric
List Moderator
elecraft.com

On 3/25/2015 5:51 PM, Bob Gibson via Elecraft wrote:
>   You guys are right!! SORRY FOR MY STUPID POST!! Sixty years ago I did not have money for a dummy load..ENJOY   73s Bob W5RG
>
>      ----- Forwarded Message -----
>    From: Fred Jensen <k6dgw at foothill.net>
>   To: elecraft at mailman.qth.net
>   Sent: Wednesday, March 25, 2015 6:41 PM
>   Subject: Re: [Elecraft] Fw: Don't have a 50W dummy load
>     
> Ummm ... several reasons.  Resistance component of an incandescent bulb
> impedance varies with the temperature [brightness] of the filament.
> They are also somewhat reactive.  Push-pull vacuum tubes and link
> coupling didn't care about SWR, I don't even remember the term in the
> ham lexicon until the Pi-network and 50 ohm output was invented.
>
> They're also not very good at the "dummy" part.  N6BT, of Force 12 fame,
> is fairly famous for his "phased illuminator," 3 300 watt bulbs mounted
> on his deck railing in a V arrangement on which he worked all
> continents.  More than once I made contacts while using a 100 watt bulb
> as my dummy load.
>
> If you're going to use the paralleled metal film resistor construction
> method, be sure to keep the resistor leads short and spaced them from
> each other.  Lead inductance will start to become a factor on 6 m and
> up.  I built mine with 40 2K 2W resistors and it works find at 100W if
> used intermittently.  It's air cooled.  Don't know how much putting it
> in oil would improve the dissipation.
>
> 73,
>
> Fred K6DGW
> - Northern California Contest Club
> - CU in the 50th Running of the Cal QSO Party 3-4 Oct 2015
> - www.cqp.org
>
>
>
>>> On Mar 25, 2015, at 14:25, Bob Gibson via Elecraft <elecraft at mailman.qth.net> wrote:
>>>
>>> HOW ABOUT A LAMP WITH 100 WATT BLUB, THATS ALL US OLD GUYS HAD!  73s Bob W5RG
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