A 3-Step Process for Optimizing the K-Line for Your Needs

Revision B-2, April 2016

The K3S transceiver has been optimized for the ham bands.  This has been borne out by its popularity with DXpeditions and Contesters.  For many people who are upgrading their stations, the K-Line also provides many options they can choose from.  At Elecraft, we get many calls about how to make these decisions.  This Application Note offers you a method to determine how you can purchase just what you need for your operating preferences.

 

Step 1:  How do you spend your Operating Time?

% CW	Percentage of your time	% DX	% Contesting	% Casual	% Fixed, Mobile or Trail Time
% Phone	Percentage of your time
% Digital	Percentage of your time
% VHF/UHF (all modes)	Percentage of your time
Typical Operating Power Levels You Use	<10 watts 10-100 watts > 100 watts
Planning to use your home rig remotely?	Yes/No
Facilities for Diversity Operations?	Yes/No
Do you want to build your K-Line?	Yes/No

 

 Step 2:  Determine what you will need with Your K3S or K-Line

Now that you have an idea of where your operating priorities are, here are some K3S configurations that you can order immediately.

 

Typical K3S Configurations for HF Operating Profiles

Power Needed	What is the Minimum I need?	Recommended additions for DX, Contesting and Casual Operating	Add for Fully Configured K-Line
<10 Watts	K3S/10 Default Filter** KUSB	Internal Tuner P3 Panadapter Digital Voice Recorder Filter Combo*	P3 + SVGA (for use with external screen) Full Filter Combo**
Between 10 and100 Watts	K3S/10 Default Filter** KUSB	Internal Tuner P3 Panadapter Filter Combo*	K3S/100 Internal Tuner P3 + SVGA (f/use with external screen) Full Filter Combo**
>100 Watts	K3S/100 KPA500 KUSB Cable KPAK3AUX Cable	KAT500 (w/AUX cable) Internal Tuner P3 Panadapter   Filter Combo*	K3S/100 KPA500 KAT500 (w./AUX cable) Internal Tuner P3 + SVGA (f/use with external screen) Full Filter Combo**
Dual Antenna and Diversity?	N/A	Add 2nd Receiver Matched Filter Sets*	Add 2nd Receiver plus Matched Filter Sets*

 * = When using dual receivers, filter sets must be matched for Diversity mode operation. See next table for filter combinations.
** = See next table for filter combinations

 

Step 3: Choose Your Filter Considerations

Now that you have determined your operating preferences and the configuration of your rig, let's turn our attention to the selection of filters.   Your choice of the combination of filters is driven by the way that you operate.  Based on the guidance from the Elecraft design team, here are some combinations recommended based on typical use patterns of DX, Contesting and Casual communities.

Starting Points for Filter Selection

Your Operating Priorities	What is the Minimum to get started?	Recommended for DX and Contesting	Recommended for Casual Operating
CW Phone Digital	2.7 kHz 500 Hz	2.8 kHz 2.1 kHz 400 Hz 250 Hz 200Hz	2.8 kHz 2.1 kHz 1 kHz 500 Hz
Phone Digital CW	2.7 kHz 500 Hz	2.8 kHz 2.1kHz 1.8 kHz 400 Hz 200Hz	2.8 kHz 2.1 kHz 1 kHz 500 Hz
CW Only	2.7 kHz 500 Hz	2.8 kHz 1 kHz 400 Hz 250 Hz 200Hz	2.7 kHz 2.1 kHz 1 kHz 500 Hz
Phone Only	2.7 kHz	2.8 kHz	2.8 kHz
Phone Digital -CW in the future	2.7 kHz	2.8 kHz	2.8 kHz

 

The filters recommended are a starting point for you to fine-tune if you wish.  Also, use the Minimum column as a way to get started and then plan to add the other filters as you find need for them.

Important Notes When Selecting Your Filters 

• There are 5 filter positions per K3S and per KRX3A. The 2.7 (or 2.8) kHz SSB filter uses one of these positions.  A 2.7 kHz SSB filter is included standard with each K3S and each KRX3A.
• On SSB the K3S must transmit through the widest standard SSB filter (either 2.7 or 2.8 kHz). (You may receive on any filter.) Again, K3S radios must have at least a 2.7 or 2.8 kHz SSB filter installed. (2.7 kHz is included with the base K3S.)  For ESSB mode, TX can be set to use the 6 kHz or 15 kHz filters (if installed) and b/w can then be set by the DSP.
• AM and FM bandwidth filters are required on the main K3S TX/RX board for TX in AM and FM modes. (Only one AM filter is required for AM TX/RX, or one FM filter for FM and AM TX/RX.) All filters can be used for RX in any mode.
• KFLMATCH - Matching of identical B/W filters for center offsets within 40 Hz of each other. (200 Hz, 500 Hz and 2.7 kHz filter pairs only.)  
  For same frequency diversity receive usage with K3S and KRX3 locked together. Set the K3S offset menu for both filters equal and to the nearest 10Hz offset approximately half way between their marked offset frequencies.
  Note: It is Best if both filters to be matched are ordered at the same time. We will try to accommodate matching to filters already shipped, but we can only guarantee a center offset match within 40 Hz if both filters are ordered at the same time, due to batch to batch manufacturing frequency changes.

 

 

What do the terms DX, Contesting and Casual use mean?

Use Profile	Characteristics
DXers	•    Working pile-ups to get that rare one •    Weak signal work in the midst of other DX chasers •    Diversity mode for being able to better hear DX stations •    Be able to have power available when I need it
Contesters	•    Competitive, score-based tuning with visual tuning •    Need quick Search-and-pounce tuning capabilities •    Need unique tools to pull out CW signals down in the noise •    Be able to use higher power when called for
Casual Users	•    Experiment with various modes of operation •    Like to check into or run nets, rag-chew and connect with friends •    Will typically prefer to have access to all HF bands •    Would like to have one cabinet to also have 2 Meter access •    May or may not need high power.
Minimum needed to get started	•    Just starting out with Ham Radio. •    Want a single, high-performance radio that can be expanded •    Wish to minimize initial cost but build a great rig the way my interests go

 

 If you know your operating style, check out our K3S packages. We incorporated the most popular filters, options and accessories into each of the packages.