cw weight reduces as speed increases

I good friend has kindly lent me his K3. I have noticed that the cw
weight changes inversely proportional to the speed setting -- just as it
does on my old K2. The timing sounds decent below about 35 wpm, but once
the speed gets to around 40 wpm, the weight becomes very light, and the
keying sounds like it's being generated by a poorly adjusted bug.

I connected up an oscilloscope to monitor the keying envelope while
sending a string of dits, and it's easily seen that at slower speeds the
dit length is greater than the space between dits. At around 35 wpm,
this reverses and the dit length becomes progressively shorter than the
space between dits.

I would expect that regardless of speed, the dit length should equal the
length of time between dits. Or, at least the ratio should remain
constant, and a function of the weight setting.

I also tried to key the radio using an external Logikey K-3 keyer which
*does* maintain a constant and equal dit-to-space ratio throughout its
range, but the K3 still shortens the dits as speed is increased.

Is there any way to fix this?

73, Dale
WA8SRA
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[wayne burdick]

Dale,

Keying weight would, in an ideal world, not change with speed. But the  
reality is that the low-noise synthesizers in both the K2 and K3 take  
some time to switch between transmit and receive. We take this into  
account, but that can only be done up to a point because of various  
timing relationships in hardware and firmware.

Please try "QRQ" mode, in which the synthesizer doesn't move. This  
allows for far more accurate timing at all speeds.

73,
Wayne
N6KR


On Sep 23, 2011, at 6:36 PM, Dale Boresz wrote:

> I good friend has kindly lent me his K3. I have noticed that the cw
> weight changes inversely proportional to the speed setting -- just  
> as it
> does on my old K2.


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Hello Wayne!

Thanks for the quick response. QRQ mode works beautifully, and the
keying sounds great now!

(I should have read the manual more closely)

73, Dale
WA8SRA

On 9/23/2011 9:52 PM, Wayne Burdick wrote:

> Dale,
>
> Keying weight would, in an ideal world, not change with speed. But the
> reality is that the low-noise synthesizers in both the K2 and K3 take
> some time to switch between transmit and receive. We take this into
> account, but that can only be done up to a point because of various
> timing relationships in hardware and firmware.
>
> Please try "QRQ" mode, in which the synthesizer doesn't move. This
> allows for far more accurate timing at all speeds.
>
> 73,
> Wayne
> N6KR
>
>
> On Sep 23, 2011, at 6:36 PM, Dale Boresz wrote:
>
>> I good friend has kindly lent me his K3. I have noticed that the cw
>> weight changes inversely proportional to the speed setting -- just as it
>> does on my old K2.
>
>
>

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