Hi George!
We start to bump up against shortening the first dit on CW when delays
longer than 20 mS are selected. We'd certainly like to support longer TX
delays, but it will take a little head scratching and f/w work to make
it happen. We'll certainly strive to do as much as we can in this area.
If you and other members on the list can send me the max delay supported
by other rigs currently on the market, that will help us figure out if
this is reasonable.
I was unaware of any commercial rig supplying much above 20-25 mS of
keyout to RF delay. The K2 provides 10-12 mS of delay and we've had
very few complaints even with that. What delay does the Pro-III support?
Were you able to drive your amplifier in semi-break-in with it? I am
unaware of any current production Ham rig that supports directly keying
high current AC relays with greater than 20-25 mS long delays. (But I
could be wrong :-) That's why many VHF ops, who require long delays for
their transverter and antenna switch chains, usually use a foot switch
to manually key everything before generating RF.
One other thought, just looking at the theoretical worst case relay
settling time may overstate the delay required. What is the time delay
for the amp RF path itself? Also, the worst case settling delay is
usually specified for DC or low freq AC loads. At RF, the contacts may
be close enough, with enough contact to provide a very low impedance RF
path well before this time, even if they are still settling.
In any case, we'll keep looking at this.
73, Eric WA6HHQ
======
George wrote:
I don't think 20 ms is enough in my case, based on my primitive research. Several
"experts" have said mine might need as much as 30-35 ms. My amp's relay is a 30 yr
old Potter & Brumfield open frame model with a 120vac coil.
To make things worse, since the K3 will not switch 120vac, I must use another relay
with a 12vdc coil in the line between the K3 and the amp, which in turn pulls in
the P&B relay. This exacerbates the matter by taking even more time, and I'm
afraid to try anything for fear it will damage the K3 and the amp. Am I wrong??
Anyone care to comment??
One of the many reasons I bought the K3 was to be able to operate at least semi
break in CW and VOX with my old amp without hot switching, by virtue of having
ample switching delay. I've waited months for the feature and am disappointed..
However, I hasten to add this: As a K2 user/owner/builder, I expected much in
the K3. I got much more than I expected. I gave up a nice Icom Pro 3 for the
K3 and don't miss the Pro 3 one iota. The K3 is unbelievable in what it can do
and how superbly it does it. And getting new firmware is icing on the cake.
But I sure wish I had 0-50ms amp delay capability! How about it, Wayne?
George, N4YM
K2 # 4758
K3 # 340
_______________________________________________
Elecraft mailing list
Post to: [email protected]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com
_______________________________________________
Elecraft mailing list
Post to: [email protected]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com
