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Finally got back to looking at this problem. In short, the problem is that when sending CW in what Hallicrafters called "break-in" mode (Operation switch in VOX position), the first dit or dah sent is severely truncated to the point that a dit might not even be heard at the other end. Looking at the timings observed by Halden, if we could just somehow lengthen the leading dit or dah by 30 ms. or so, we would mask the problem and all would be well. I read through a lot of posts on the K1EL group here on groups.io (Winkeyer info) and found that K1EL had already thought of that solution and built it into the Winkeyer USB.

In the Winkeyer USB settings, there's a parameter called "1stExt". If you put a value in there in milliseconds, Winkeyer will automatically lengthen the first dit or dah sent by that amount of time and all other dits and dahs are unaffected. I used the Winkey utility called "WinKey2 Standalone Editor" to play with the value and at 30 ms. it sounds pretty good. Later I'll hook up the scope and make a final adjustment of the value. This solution makes the HT-44 a very decent CW rig where before it was useless to me.

73, Floyd - K8AC

Here's a scope trace of sending three dits at around 25 wpm. Note the shortened length of the first dit and the lower output level compared to the second and third dits.



Here's how three dits look after Winkeyer USB is setup to extend the first dit or dah by 30 milliseconds. While the first dit is now of the proper length, the power level is still lower than that of the second and third dits. The parameter used to lengthen the first code element by the Winkeyer is called "1stExt" for first extension. It works for hand sent code or for messages sent by the PC to the Winkeyer.



Another oddity - there's always a very short noise burst about 25 ms. prior to the start of a dit or dah. Not noticeable on the receiver.



Looking close at the envelope for a dit, the rise and fall times could be a bit longer, but the shapes are pretty good. Here you can see a variation of several percent in the output power level over the duration of the dit.