[Elecraft] K3 Bootup sequence?

[Edward R Cole]

Vic,

Yes, a better way would be using a diode thru a switch to ground.  In 
my diagrams the 1K resistor probably should be retained so the diode 
does not draw excessive current when grounded (not needed if you use 
the 2.2K to 10K dropping resistor in place of the 5v regulator)

In my circuits a relay  (shown as K4 "TX2 SEQ Stage") in my sequencer 
grounds the diode.  This enables the transmitter after all preamps, 
TR relays, and other transmitting equipment have been switched into 
"transmit mode".  I only use inhibit on 6m and above bands and this 
is to avoid hot switching my eme QRO equipment.

The VOX/AUTO-OFF is probably more convenient to avoid RS232 start up 
keying.  No extra circuitry needed.

73, Ed - KL7UW

From: Vic K2VCO <k2vco.vic at gmail.com>
To: elecraft at mailman.qth.net
Subject: Re: [Elecraft] K3 Bootup sequence?
Message-ID: <51CA2CC7.60405 at gmail.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

If you do this, make sure that when you remove the 5v pin 7 is either 
grounded directly or
via a resistor. if you let it float, it may inhibit output in that condition.

Yes, I see that Ed didn't do that in his schematic -- maybe it's 
rig-dependent, but I've
had this problem.



73, Ed - KL7UW
http://www.kl7uw.com
dubususa at gmail.com
"Kits made by KL7UW"