[Elecraft] K2 filter attenuation

[Don Brown]

Hi

No this is not normal for a properly aligned K2. If you have FL4 set up a=
t 100 Hz or less (I set mine to 150) then you may hear a small drop in si=
gnal but it should not go away. All of the other filters should not chang=
e the signal strength at all. As the filters get narrower the noise and a=
djacent signal go away not the desired signal. =20

If your radio does not perform this way then you need to realign the filt=
ers using spectrogram and a noise source. The settings in the K2 manual w=
ill get your radio working, but not to the peak performance. Spectrogram =
or some other audio spectrum analyzer program with a broad band noise gen=
erator as a signal source is the only easy way to get your radio aligned =
perfectly. =20

A few times I just could not get the radio to set up so it worked properl=
y. I could hear the tone on CW reverse but it would go away on CW normal.=
 I checked the alignment several times and compared the settings to the K=
2 manual and they were in the ball park but it just would not work the wa=
y I new it should. I finally did a hard reset of the K2 (hold 4,5 and 6 o=
n power up) and set up the filters with Spectrogram and everything fell i=
nto line. You may need to do this as a last resort if you cannot get it t=
o align. You may need to do the CAL PLL also if you do the reset. The res=
et clears out all of the memory and loads the factory defaults.

The procedure I outlined in my previous post is a performance check not a=
n alignment technique. It tells you if you have it set up right but you s=
till need to align the radio by Tom's method described on the website usi=
ng Spectrogram and the noise generator.

Don Brown
KD5NDB

7 K2's and counting
3 K1's
4 KPA100
all Options


----- Original Message -----
From: COLIN WHITMORE
Sent: Tuesday, October 15, 2002 11:55 PM
To: Elecraft
Subject: [Elecraft] K2 filter attenuation

I've noticed that when trying to grab a weak signal I have to keep the fi=
lter wide. If I try to narrow the filter selection to block out an adjace=
nt signal there seems to be some (significant) attenuation to the filter.=
 That's not a problem for strong signals but for the very weak signals I =
will totally lose the station. So if I want to work a weak signal I have =
to put up with other stations well off the centered frequency. Is this no=
rmal? I've checked the alignment (according to Don, KD5NDB) and the 40M b=
irdie remains fairly consistent in pitch as I switch through the filters.=
 Any suggestions?

Cheers,
Colin
N=D8YGY


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