10 November 2009

FT817 keypad - first quirk reported

A builder of my FT-817 keypad has reported me a problem using onboard dynamic memories and "far" QSYs. It was reported while testing a 38400 baud keypad version (default is 4800 baud), but the glitch is caused by RTX internals and not the keypad firmware itself.

I could reproduce the same behavior but not deterministically! Try it yourself:
  • write 3700 kHz LSB in onboard memory #1
  • write 145500 kHz FM in onboard memory #2
Set your VFO to, say, 20m band. Recall memory #1, then recall memory #2: it might happen that the mode stays LSB and doesn't change to FM.

Quick fix: recall memory #2 and the mode is set properly.

Cause. I think the internal CPU of the FT-817 is busy doing something else when asking for a large QSY and ignores the mode change command. The 100ms delay between the two is not enough.

Fix: new firmwares include a 200ms delay that seems to make both the operator and FT-817 happy.

Freely available firmware will be updates shortly.

Since this glitch is non-blocking for keypad functions and doesn't hang the radio I will not issue a recall statement for already shipped chips.