DISCONTINUED Elecraft K4D-F/KAT4 FITTED - serial number 0637

Our new K4 harnesses the latest in signal processing while retaining the best aspects of the K3S and P3. The resulting user interface makes the technology transparent, allowing you to focus on working the world.

The K4 includes dual receive over 100 kHz to 54 MHz. Since it utilizes direct sampling, there’s no need for crystal filters in the K4 or K4D, for extreme-signal environments

The K4 features a large, full-colour touch display, combined with a rich set of real controls. Per-VFO transmit metering makes split mode completely foolproof. Band-stacking switches and per-receiver controls are both intuitive and versatile, adapting to operating context.

The KAT4 is the most advanced built-in ATU we've ever offered. It also adds a powerful receive antenna switching matrix..

A side benefit of the KAT4's wide tuning range is that it can often match antennas on bands they weren't designed for. For example, a typical tri-band beam (20/15/10 m) can usually be loaded on one or more nearby WARC bands (30/17/12 meters). (Actual losses will vary with type of feed line used, whether there's a balun in the system, etc.; in some cases reduced power may be recommended.

The KAT4's L network was optimized for low stray impedance, so it can even improve the match between the K4 and an external amplifier. This is especially true on the highest bands (10 and 6 meters). In many cases, this can allow the K4's 100 W PA to run more efficiently in the presence of a small mismatch.

The KAT4 represents a clear advance in antenna management. There are three transmit/receive antennas (ANT 1/2/3), with your selections stored on a per-band basis. In addition, a second relay switching matrix is provided to allow either of the two non-transmit antennas to be used as a receive antenna for the main receiver, sub receiver, or both