[Elecraft] K3 Burn In

[John King]

Disclaimer - the following test method is not approved or 
sanctioned by Elecraft. Conduct any testing at your own risk.

I work in Quality Assurance in my day job (30 years and counting.)

Long before FD I performed a 24 hour endurance test on my K3
to approximate worst-case FD conditions. I recorded a CQ FD message
similar to the actual message we would be using at FD into one of
the K3's message memories, then set the message repeat time to
minimum. The K3's output power was set to 120 Watts and the rig
was connected to a 50 ohm dummy load with a Bird thruline wattmeter
in line. The DC input voltage was set to 13.5 volts. The test was
performed at ambient room temp, about 24 degrees C. The K3 sent
the continuous message loop for a 24 hour period without incident.

The actual environmental conditions at our FD were a bit more 
severe than the test conditions above. The K3 was operated in a 
4-man dome tent exposed to full sun with an outside air temp 
approaching 90 degrees. We didn't measure the actual temperature 
inside the tent, but my informal assessment was "hot as hell." 
Of course, the transmit duty cycle in actual FD use was less 
demanding than the test duty cycle. I had high confidence that 
the K3 would be up to the task, and it was.

I'm sorry to hear about your failure at FD. I have heard no other
reports of FD failures, and to my knowledge the VP6DX crew had
no failures during their operation earlier this year. It may be 
of small comfort to you, but I regard your failure as an anomaly
- stuff happens. Overall, the K3 is establishing a reputation as
a very reliable field rig.


73,
  john  WA1ABI

 




> 
> Has anyone done a burn in on their radios to test?  They rate to 100W
> 100% duty cycle for 10 minutes.  I'm sure there is quite a bit of
> headroom in that too.  Has anyone tested to that?  Do any of the
> Elecraft guys object to that type of testing?  
> 
> I had a strange failure at FD this year and worry that unless I do a
> burn in like that once it gets back that my normal amount of operation
> will take quite a while to emulate what the rig saw during field day.  
>