[TowerTalk] Balun question

jeremy-ca km1h at jeremy.mv.com
Thu Jun 14 19:26:13 EDT 2007




> On Thu, 14 Jun 2007 15:07:59 -0400, jeremy-ca wrote:
>
>>I last looked.
>>Since many hams tend to be cheap their view of ordinary coax would give
>>excessive leakage from the center conductor and possibly creating all 
>>sorts
>>of non linear problems with the ferrite.
>
> Anything is possible, of course, but coax would have to be pretty awful 
> for
> enough field from the differential signal to cause significant heating. 
> You can
> convince yourself of this by winding some chokes with lousy coax, 
> transmitting
> through them, and feeling the heat (or lack thereof). If more people did 
> this,
> there would be a lot more weeping and knashing of teeth about dissipation 
> in
> chokes. I can imagine crummy coax on a 100 w transmitter, but that's a lot 
> less
> likely with the ham is running QRO. 10% leakage is a LOT of leakage, and 
> that's
> only 10 watts with a 100 w transmitter.
>

Heat isnt the issue as I mentioned in another reply.



> In the tutorial, I described a simple series of experiments that any ham 
> can do
> with some toroid cores, some twinlead, some coax, and a 100W transmitter. 
> The
> results are quite instructive.

Im sure they are. Ive been using ferrites and powdered iron in both lab and 
home enviroments for around 40 years from DC to 75 gHz and never stop 
learning about them.

Carl
KM1H


>
> 73,
>
> Jim Brown K9YC
>
>
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk at contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
> 



More information about the TowerTalk mailing list