[Elecraft] Key Clicks

[John Simmons]

Oh, please, please bring back the CW note of the Drake 4-line!

-de John NI0K

Bob McGraw K4TAX wrote on 6/6/2020 10:59 PM:
> There are actually 2 time elements involved.  First is the time 
> between key closure and the amp key command.  This is approximately 
> 3ms of processing time inside the radio.  The second is amp key 
> command to RF generation out of the radio.  This is the 5ms between 
> amp key command and RF generation.    These are summed together to get 
> the total time from Key closure to  RF generation of about 8ms.
>
> One other company to which I'm very familiar,  specs their radio as 15 
> ms RF delay.  What is not disclosed is a breakdown of this 15ms,  that 
> 7 ms of the total time occurs from key closure to amp key command, 
> thus leaving 8ms from amp key command to RF generation.  This requires 
> the amp to switch in 7ms or less.   A mechanical relay is really being 
> pushed to accomplish this fact. This 15ms delay is not user 
> adjustable. And the CW rise and fall time is 5ms.  A bit fast for a 
> really clean signal.    Another model of the brand offers and 
> adjustable CW rise and fall time adjustable between 3 - 10 ms.  The 
> longer time makes for a much cleaner CW signal.  Again the delay from 
> key closure to RF generation is in the order of 15ms.
>
> Older amp designs, typically those that do not clearly provide QSK 
> identification or mode, are typically not suitable for QSK operation. 
> Thus switching one of these amps at the faster speeds will most likely 
> cause hot switching, resulting in key clicks and eventually relay 
> failure.
>
> I've found the K3S and KPA500 to produce some of the cleanest CW 
> signals on the bands.   Timing is the secret and the design team at 
> Elecraft have focused heavily on this aspect of these products.
>
> 73
>
> Bob, K4TAX
>
>
> On 6/6/2020 10:19 PM, Victor Rosenthal 4X6GP wrote:
>> In fact, it's closer to 5-6 ms when set to 8. And of course it 
>> depends on the amp. A general rule to "set it to 9" is silly. It just 
>> has to give the relays time to settle down.
>>
>>
>> 73,
>> Victor, 4X6GP
>> Rehovot, Israel
>> Formerly K2VCO
>> CWops no. 5
>> http://www.qsl.net/k2vco/
>> On 07-Jun-2020 04:00, David Gilbert wrote:
>>> QSK has everything to do with it.  If you hot switch the amp you create
>>> sharp waveforms every element even if the K3 keying is soft. The
>>> discussion on the contesting forum included comments that the default
>>> setting for TXDELAY on the K3 (apparently 008) isn't long enough and 
>>> that
>>> it should be set to 009.  Not sure which amps were being considered.
>>>
>>> 73,
>>> Dave   AB7E
>>>
>
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