[CQ-Contest] CW Pile-up Handling

k3bu at optimum.net k3bu at optimum.net
Wed Aug 29 17:03:38 EDT 2012

K4BAI wrote:

>>In prior years, I used Kenwood radios (TS440, TS450, TS850S) from 
8P9HT/8P9Z, J77J, and NQ4I. If there wasn't a lot of QRM, the CW 
sounded real good in Kenwood radios (better than in Yaesu or Icom 
generally), but a big pileup resulted in one big bubble of sound and it 
was almost impossible to get a letter out of it. With Yaesu radios, 
FT1000, FT1000D, FT1000MP, Mark V, FT5000, etc. it happens almost never. 

Some of the earlier ones require an AGC mod to avoid the problem. I 
haven't yet experienced any such constant undecipherable CW pileup noise 
with Elecraft radios either. Nor with Icom radios. (I should note that 
I have no experience with Kenwood radios newer than the TS850S.)<<
Blame the modern technolgy. 
Cascaded Xral filtering, upconversion mixing, DSP processing and demodulation.
Best receiver standing?  Drake R4B - one Xtal "roofing" (Sherwood) filter, minimum ringing and mushing up of signals (more pole and cascaded filters add ringing and mushing/stretching signals)
IF chain is using LC tuned IF filters, no ringing and stretching of signals and static crashes. 
True analog product detector, no chance of confused DSP.
As you describe riding the RF and AF gains works and makes a difference.
Elecraft K3 comes close and does remarkable job in processing signals.
Yuri K3BU.us

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