K3 Operating Tips

From Zerobeat

• AM SWL using Stock 2.7 Filter

Using K3's Memories (N6XI)

Frequency memory control is very flexible, more than compensating for the lack of dedicated, individual band buttons on the compact front panel. There are five ways to select frequency:

  1. The BAND up/down rocker switch cycles through bands one per tap,
  taking you to the previous frequency (and mode and filter, etc.) that you
  used on that band. This is effective but slow.
  2. Type a frequency into your logging program and it will command the
  K3 to that frequency (etc. - I think mode selection will eventually be based
  on national allocations).
  3. Tap M->V and one of the numeric buttons to select one of 10 global
  pre-set frequencies (and mode and filter, etc.).
  4. Tap M->V, turn the VFO A knob and tap M->V again to select one of
  100 global pre-set frequencies (etc.) including the 10 that are accessible
  via a numeric button.
  5. Tap M->V and one of the four Mn buttons to select one of 4 per-band
  frequencies (etc.).

It's methods 3 and 5 above, the "two-tap" methods, that I really like. I have set up my 10 numeric button memories with mnemonic settings as follows:

1 - 10m 2 - 20m 3 - 30m 4 - 40m 5 - 15m 6 - 6m 7 - 17m 8 - 80m 9 - 12m (well, no mnemonic there...) 0 - 160m

Thus, with two button taps I can be on a preferred CW frequency on any band with my mode, filters and other preferences all set.

I have also set up Mn for each band as follows:

M1 - CW M2 - SSB M3 - RTTY

Thus, once I am on a band I can change mode (and frequency, filters, etc.) with two taps. I use M4 as a temporary scratchpad. I may revert M3 to that purpose as well since I don't operate much RTTY.

(N1EU comment: it doesn't appear to me that filtering is being stored in the memories)

Tuning Rate Settings (N1EU)

set VFO FST to 20 to make the fast tuning rate more usable

 CW: 1Khz/rev slow, 2Khz/rev fast: VFO CTS=100 VFO FST=20 VFO CRS=50
SSB: 2Khz/rev slow, 4Khz/rev fast: VFO CTS=200 VFO FST=20 VFO CRS=50

Noise Reduction (KK7P)

The first value you see -- the Fx -- has to do with the aggressiveness of the filter. The second value you see specifies the blend of processed and unprocessed audio.

Keep in mind always that the denoiser is not a denoiser; it is a signal enhancer. It will act to suppress *everything* until it decides there is some sort of signal present, then act to pass that signal. The more the signal appears to be a pure tone (like CW) the faster and more decisively the algorithm acts. The less it looks like a signal (noisy SSB comes to mind) the slower and less decisively the algorithm acts. This is why the audio level is low to begin with.

For CW with reasonable S/N, it usually quickly builds up to the same overall amplitude as without the NR.

For SSB with poor S/N, it builds up slowly and to a lesser overall amplitude.

Thus, observations that the signal amplitude sometimes or often appears reduced are correct. The disagreements about how much it is reduced are also correct.

It depends on the NR settings, the S/N of the signal you are listening to at the moment, the type of signal, the IF and AF bandwidth...

FWIW, I usually have mine set to F1-1 or F1-2 for SSB operation. YMMV.