Towertalk
[Top] [All Lists]

Re: [TowerTalk] Baluns/tutorial/notes.

To: Dan Zimmerman N3OX <n3ox@n3ox.net>
Subject: Re: [TowerTalk] Baluns/tutorial/notes.
From: jimlux <jimlux@earthlink.net>
Date: Sat, 22 May 2010 18:12:36 -0700
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>
Dan Zimmerman N3OX wrote:
>> Of course, how much power gets dissipated depends a lot on the specific
>> application. But, is there some sort of standard test condition that would
>> be representative?
> 
> 
> I dunno.  There's no "typical" or "standard" common mode source and load
> impedances, and they're harder for hams to calculate and control.   I think
> the best you can do is publish the impedance and the safe allowable average
> power dissipation at given ambient temperatures: Then people can
> put together an EZNEC model or measure the residual current with a
> calibrated ammeter and short duty cycle, and calculate the dissipation and
> compare if they want.

Good point..

I was thinking that most mfrs aren't going to publish this, so someone 
else would have to do the measurements.  Hence, the idea of a standard 
test condition.

> That  antenna is just too strong of a common mode source for chokes that
> would take the common mode stress of a more typical antenna system with 10kW
> applied.
> 
> Given the high Q, large stored energy systems we can practically build in
> our backyards, it's  not too hard to cook up a system that shows that "a lot
> of common mode impedance" is all relative.  I admit it's a pathological
> situation.   But sometimes that happens :-)

hmm..


_______________________________________________



_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk

<Prev in Thread] Current Thread [Next in Thread>