You guys should go back to the first message in this thread and reread it.

This is not a key click situation. It is band-limited noise and can be heard in XMIT, no need for keying. I believe it is thermally sensitive; worse right after powering up the radio and diminishing with warm up.

On 50 MHz. I can see over 50W indicated on the KPA500 bar graph.

Wes  N7WS


 On 7/27/2017 5:38 AM, EUGENE GABRY wrote:
Hi Dan,


I see exactly the same thing, although, on my analog watt meter, even running 
dits continuously, I don't see any movement of the needle. Must be micro watts 
leaking in extremely fast/short duration. I guess I would have thought 
precautions for clamping down in the TX chain, prior to antenna coupling, would 
have been implemented, so no RF leaking could occur.

I'm even more curious now to find out what all is engaging during key down in 
test mode to be drawing an additional 1.5 amps. I'm assuming it should only be 
circuitry to engage cw keyer and side tone in test mode, but obviously a path 
in the TX chain is activating that maybe should not, allowing leak through.

Guess I'll pop this thing open for the first time an do some tracing :)


I've added our thread back to the reflector, as I don't think this should be a 
normal operating function. If the intent of a test mode is to test without 
actually emitting a signal, then this oddity of RF leaking is not acceptable.


73 Gene, N9TF

On July 27, 2017 at 6:49 AM Dan Atchison <n...@aol.com> wrote:

     I think that is normal, Gene, as all the oscillators in the TX chain are 
working.  What I and others are seeing is short spikes of power when doing CW 
in TX mode.

     Try this:  Hook up your K3s to a dummy load through a digital wattmeter and send a long string 
of dots.  You will eventually see power out - enough power to show SWR.  The resultant signal is 
heard as key clicks and can be heard as key clicks (with no CW "tone") miles away.  It's 
a very short duration signal (only microseconds of an entire dit) and is only heard as clicks.  
Note, you can only "see" the issue with a good instantaneous reading digital wattmeter 
because of the short duration.  I measure several watts of this intermittent click.

     73
     Dan





     On 7/26/2017 11:00 PM, EUGENE GABRY wrote:

         > >
         Out of curiosity I just checked this with my K3S and found the same 
oddity. During CW key down into a dummy load in TX Test mode the K3S draws 2.5 
amps from the 1 amp in RX, and the hash signal heard in another receiver into a 
different dummy load appears to be 2.7Khz wide. Starts out as full scale signal 
in the receiver and drops quickly to S5 but never goes away during key down. 
Cant detect any power indication on the dummy load power meter during key down. 
Maybe a pre driver stage getting bias in TEST MODE?
         Interesting...

         Gene
         N9TF
             > > >
             On July 26, 2017 at 9:03 AM Dan Atchison via Elecraft 
<elecraft@mailman.qth.net> mailto:elecraft@mailman.qth.net wrote:

         > >
             > > >
             Yes, the K3s does put out power during this clicking and it has 
been
             observed by operators who live close by.  Power and SWR are noted 
on a
             digital power meter.

             73,
             Dan


         > >
     >

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