[Elecraft] K3: killing RX key clicks

[Ian White GM3SEK]

Paul Christensen wrote:
>> The 'RC rise/decay' wave shape that was in the handbooks for many years
>> is actually a *bad* shape because it has a very sharp corner on key-up.
>
>Ian, *bad* may be a bit too harsh.  The League's optimized envelope was 
>described during a time when only simple R/C values were used to 
>develop a keyed envelope. I'm not sure how one would have produced an 
>economical Blackman-Harris or raised cosine function until say...the 
>early to mid '90s. How would you have done it? Probably the only 
>solution at the time was to set leading and trailing edges produced by 
>the R/C network so soft that they're painful to copy.
>
My criticism was that because R/C shaping was judged to be the only 
available technology, it was wrongly promoted as being the optimum that 
designers should aim for. Given better information, I believe designers 
could have produced analog circuits to approximate the true optimum 
shape... but that didn't happen.


-- 

73 from Ian GM3SEK
http://www.ifwtech.co.uk/g3sek