[Elecraft] K3 TX delay

[Jim Brown]

On 2/15/2012 8:39 AM, briana wrote:
> On older amps that could be 15ms or more.

The issue is not OLDER amps, it is poorly designed amps (or el cheapo 
amps).  My Ten Tec Titan 425s, which were designed in the late 70s and 
built in the early 80s, were designed for QSK, and key reliably at 
8msec. They use good vacuum relays (the same used by Alpha) and smart 
control circuitry to positively prevent hot switching.  El cheapo amps 
with open frame relays (like some MFJ/Ameritrons I've seen) are never 
going to follow CW, no matter what is done at the rig.

Now, there ARE techniques that can be used to speed up a slow relay.  
Quite a few years ago, K6XX, a top contester and superb EE who now works 
for Elecraft, designed a simple circuit that adds a short, higher 
voltage spike to the keying signal, and causes the relay to pull in a 
bit faster. This circuit must be added to the amp.

73, Jim K9YC