[Elecraft] New K3/K3S Beta Firmware, rev. 5.33: Diversity mode works with mixed filters; "Safe" option for PTT-KEY via USB; etc.

[Wayne Burdick]

Hi all,

K3/K3S beta firmware rev. 5.33 is now available on our K3 software page. This release corrects a problem with diversity mode when used with the KSYN3A synthesizer; now, any combination of crystal filters can be used on the main and sub receivers. It also improves the way PTT and KEY activation work via the new USB port on the K3S.

In addition, there are a few important enhancements for K3/K3S software application developers. In conjunction with this, we've posted a new edition of the K3S/K3/KX3 Programmer's Reference (rev. F2).

See release notes below for full details. For instructions on installing beta releases, refer to our K3 software page.

73,
Wayne
N6KR

* * *

MCU 5.33 / DSP 2.86 / FPF 1.23, 8-3-2015

* DIVERSITY WORKS WITH MISMATCHED MAIN/SUB RX FILTERS:  Diversity mode in the K3S (or a K3 with the KSYN3A installed) now works with any combination of main/sub RX crystal filters. They can have different bandwidths or offsets, and it's not necessary to have an equal number of filters in each receiver. Note: Matched filters are optimal for diversity, but non-matched filters will still perform well.

* PTT/KEY USE WITH THE USB PORT IMPROVED:  PC applications can activate PTT and KEY at the K3S via the USB port's RTS/DTR signals. However, initial setup of the rig's USB port by the PC may cause pulsed or continuous activation of the transmitter. This can happen if the computer is turned on after the K3S, or if the USB cable is not connected. There is now a "Safe" mode (the default) which disables PTT-KEY transmit until the K3S receives a command via USB, such as a read of the rig's VFO frequency. To turn on safe mode on/off, go into CONFIG:PTT-KEY and tap '1' to select "USB SAFE" or "UNSAFE". Exit the menu and turn the K3S off/on. Applications that use PTT-KEY via USB but never send commands may require "UNSAFE" mode. In this case, unwanted transmit can be avoided by turning the PC on before the K3S.

* CANCELLING UNEXPECTED PTT-KEY ACTIVATION:  If an external source (usually a PC) activates PTT or KEY unexpectedly, you can cancel transmit by tapping the XMIT switch. This will show ERR KEY or ERR PTT on VFO B. Once the PTT or KEY source as been removed, transmit will be re-enabled. If the cause may be unneeded PTT-KEY activation via the USB port, go into the CONFIG:PTT-KEY menu entry and set the parameter to OFF-OFF.

For Application Developers (also see Programmer's Reference, rev. F2):

* PARAMETER ADJUSTMENT VIA "UP" and "DN" COMMANDS:  UP and DN now apply to all settings adjusted using VFO A/B, including: NB, NR, manual notch, pitch, and text decode . (It also still applies to the menu.) It does NOT apply to special displays controlled by VFO B (use DB), or to settings controlled by the small encoders.

* OM (OPTION MODULE) COMMAND CHANGES:  Three new single-letter fields have been added to the OM command:  'L' (low-noise amp/preamp2 available on present band), 'V' (KSYN3A installed, allowing the VFO to tune down to 100 kHz), and 'R' (K3S RF board in use; see impact on RA command, below). Note that 'L' (preamp 2) only applies on 12/10/6 meters. Preamp 2 is located on the new KXV3B module.

* RA (ATTENUATOR) COMMAND FORMAT CHANGE: If a K3S RF board is in use (determined using the OM command, above), the set/response format of the RA command uses dB values  (RA00/05/10/15). The K3 format is still RA00/01. Note:  5 and 15 dB attenuator settings only apply to the main RX. The sub RX attenuator is 10 dB, even in the K3S. But if a K3S RF board is detected, the sub RX RA format is RA00/10.