[Elecraft] Firmware Failure

[Don Wilhelm]

Jimmy,

That MCU LD should only happen on rare occasions, like when power is 
interrupted or the computer 'glitches' during a firmware download.
When does it occur?  At Power ON time?
If so, how are you turning off your K3?  You must use the POWER button 
to turn the K3 off.  Powering off your power supply can cause that failure.
You may want to check your power supply to see if it is dropping out, or 
if the power cable is faulty.

The firmware is stored in EEPROM and there is no need for a 'backup 
battery'.  The only battery in the K3 is the coin battery that runs the 
clock.

73,
Don W3FPR

On 4/5/2016 4:49 PM, James D. (Jimmy) Walker, Jr. via Elecraft wrote:
> I wrote a few months ago about the strange occurrence of finding my firmware missing or corrupted on my K-3. In it’s state of failure it displays MCU LD on a dark screen. The Transmit light blinks on and off. My computer cannot detect the K-3 to reload the firmware. The problem has occurred several times. The solution, inconvenient but workable, is to disconnect the P-3 and hook the computer up directly to the K-3. In doing so, I can reload the firmware. My question is, “Why does my K-3 lose it’s mind?” Is there some battery that backs up the firmware? Could such a battery be dead as happens sometimes in older computers? This is very inconvenient. Help please.
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