[ARC5] SCR-274N Antenna Matching

[Mike Hanz]

On 8/22/2014 1:41 PM, Dennis DuValll via ARC5 wrote:

> In my LONG term experience (60+ years) with these little beasts a simple series cap is sufficient for matching a 50/75 ohm load, 100pf for 80/75 and 50pf for 40M.

No question, Mac.  There are dozens of different matching networks that 
could be used - Terman and networking textbooks are full of 'em.

> Also, don't understand the fascination with UNUNs and their toroidal relatives.

That's because you're thinking like an engineer, and I was with you 
about the same number of years ago. :-)   The difference now is the 
desire of some to operate the sets as they were in the original 
aircraft, and to me, that always meant getting that blasted RF current 
meter to do something other than reading zero.  It ain't about 
efficiency, it ain't even about getting a perfect match...it's about 
getting that meter to bump up to what it did back in 1945.  The easiest 
way to do that is to use an UNUN.  It's not for everyone, and goodness 
knows I never look down my nose at those who like to get the absolute 
greatest amount of power transfer out of their equipment, but I reserve 
that kind of tweaking for home brew transmitters and the like.  It's a 
different mindset, sorta the same reason we put up with limited keying 
speeds, earphones, and the click and clack of multiple relays.  It's all 
music to the ears.

Bottom line:  It's nostalgia, man!

VY 73,
Mike  KC4TOS