[Elecraft] New KX3 field-test firmware (rev. 1.95): TX RF output delay added for slow high-power amplifiers

[Wayne Burdick]

Hi all,

We've learned from some KX3/KXPA100 customers that their high-power amplifiers require a delay from keyline assertion to application RF drive. The KX3 and KXPA100 have such fast QSK (break-in keying) that RF is present only 5 ms after the keyline goes low. This is too fast for some amplifiers that use sluggish T/R relays.

If you have a slow-to-key-up external amplifier, and you'd like to try adding an TX RF delay, please email me directly and I'll send you the latest field-test KX3 firmware. The delay can be varied from about 5 to 20 milliseconds. 

This new release also fixes a problem with the KX3's TUN PWR function when used with the KXPA100. Previously, going into TUNE mode with a TUN PWR value set up in the menu would cause a power-output spike at the KXPA100. Now, power is cleanly dropped to 10 W or less, as set using MENU:TUN PWR, when TUNE is used.

73,
Wayne
N6KR