Bob,
I do not know the sequence for power-up diagnostics that are run by the
K1 - perhaps Wayne or someone else having access to the code (Elecraft
proprietary) can provide that information for you. All I can say is
that the firmware is stopping execution early in the cycle. A heat/cold
related problem is usually a bad solder connection, but it can also be
the result of a temperature sensitive component (that happens rarely,
but it can occur).
Can I assume that it just quits processing and never indicates an "Enn"
message in the display?
Most times I have encountered that symptom, the firmware chip itself is
at fault. If you have another K1, try swapping the firmware chip to
test it.
Things that are checked for error state are the Filter Board IOC
(usually results in an E27 or E28 message), and the EEPROM (usually
results in E30, E31 or E32).
You may want to check the oscillator components (X1, C1 and C2) and be
certain they provide a clock to the microprocessor.
The AUXBUS could also have a fault that is halting the firmware
execution of instructions.
73,
Don W3FPR
Bob VanFossen wrote:
I have just finished my second K1. It seems to have an intermittent and
apparently temperature sensitive problem.
Symptoms are: on power up, the yellow LED turns on and stays there. If the
room temp is fairly low, heating the back of the front panel (and
consequentially the RF board) causes it to resume normal power up, and then
everything is normal. Cooling it down does NOT cause a failure.
Normal power up sequence is a quick blink of the Yellow LED, followed by a
longer blink of the same LED then the RED Green then freq display. On
Failure, there is NO blink, just steady yellow.
Can anyone lead me thru the power up diagnostic and just what is happening
that SHOULD cause the Yellow led to turn off initially? I don't even know
where in the circuitry start!
When this K1 completes it's power up, it works flawlessly! It only fails at
power up. It also seems to work OK if VERY cold, or at normal room temp.
HELP!!!
Bob VanFossen, K4DJG
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