[Elecraft] Matched Filter Crystals

[Mark J. Dulcey]

Paul Jensen wrote:
>>This may be na=EFve, but.....  on the Elecraft site at 'K2 PARTS AND MO=
D
>>KITS' I saw "K2KSB2XTLS Matched Filter Crystals (14) For existing K2 an=
d
>>KSB2 combinations". I have a long stalled K2 kit that I am 'building',
=20
> This is a major upgrade and would recommend everyone do it.  For the $1=
5
> cost and 30 minutes of work (with a hakko 808 desoldering tool), this i=
s a
> no-brainer.  I also removed c180 (as part of the 2cd Xtal mod).

I thought that if you have a recent K2 and KSB2, you already have crystal=
s that are matched as well as the ones in the kit, so it's not useful at =
all. Perhaps Elecraft can offer an opinion on which serial numbers are li=
kely to be helped by the upgrade, and which ones don't need it.

Checking your filter shape with Spectrogram or similar software may also =
help. If your filter shapes are already good, regardless of serial number=
, the upgrade probably isn't called for - although the early crystals wer=
en't matched as carefully, some builders may have gotten a good set by lu=
ck of the draw.