[Elecraft] balun

[Vic K2VCO]

mc wrote:

> there is comment on the 
> balun pages  that says there is no real good balun for low power,  my 
> question is why not, is it not the purpose to keep everything in balance 
> to get the best out of your antenna no matter the power. the eham site 
> does not offer any explanations on this but one HAM operator says DXE 
> balms claim to fame is high power out puts.

If the balun is inefficient, the loss will be the same in DB at QRP or 
QRO.  If the balun has a loss of, say 3 DB, then it will make your KW 
sound like 500 watts and your 5 watts sound like 2.5.

Having said that, power loss is power converted to heat, so you might 
not notice a lossy balun when operating QRP; at QRO it would heat and 
possibly burn up.

Finally, a balun may be more or less effective at reducing common mode 
currents (that is, converting between balanced/unbalanced), apart from 
losses.  And one balun may have a wider frequency range in which it is 
efficient and effective than another.

So there is definitely a sense in which one balun is better than 
another, even for QRP.

-- 
73,
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco