[Amps] Fwd: Fwd: *** PGXL Questions on CW Operation

[Bob Wilson, N6TV]

On Wed, Oct 31, 2018 at 7:05 AM Jim Garland <4cx250b at miamioh.edu> wrote:
(snip)

> *While PG-XL is not designed for full QSK, it is designed for fast
> switching times as low as 10 ms. **We do NOT hot switch the relays.  The
> amplifier also provides an inhibit output that can be used with some
> radios that provide for that capability.  This is not needed with
> FlexRadio since all control and inhibit commands are sent over Ethernet.*
>
> **For other brands of radios, we will soon see a shortening to less than
> 15 ms.
>
> *The relays are rated for a maximum contact bounce of 7 ms.  That plus
> some time to control the relay we allow for 10 ms.  This is on the order
> of the fastest transceiver key down to RF out.


One should remind 4O3A, K5SDR, and K9CT that the Elecraft K3 typically
outputs RF only 6 ms after KEY OUT goes low (with CONFIG: TX DLY nor 008),
and only 4.6 ms when CONFIG:CW QRQ is ON.  And as W0QE documented
<http://www.w0qe.com/amplifier_timing.html>, typical Icom rigs provide only
10-11 ms TX DLY.

Sounds like any K3 owners should be warned to set TX DLY to at least
012-015 when using this amp., and add external "1st element" keying
compensation to prevent the first dot or dash from being severely truncated
by the K3 (happens when you increase TX DLY and use VOX, with no external
PTT input).

73,
Bob, N6TV