K3: TRN5 failed

classic Classic list List threaded Threaded
1 message Options
Reply | Threaded
Open this post in threaded view
|

K3: TRN5 failed

Edward R Cole
I was plagued by the K3 not transmitting in DATA-A mode on 1296 with
a transverter.  I had the KXV3 programmed for 1296 transverter with
XV5 which should send a HI output on BAND0 when TRN5 is
programmed.  I first noticed I could transmit if I had 144 selected
(XV1) which uses the same IF of 28-MHz.  Finally dawned on me that I
was not getting BAND0=HI in 1296 which controls my INHIBIT=HI.  I
reprogrammed XV5 to be TRN7 and everything works (TRN7 outputs BAND0=HI, also).

I am not using any of the other BANDn output lines at the present.

I guess there is failure in the K3 logic for TRN5.  That it a bit
surprising as I feed BAND0 to the gate of a 2N2222 thru a high
resistance.  The transistor is a relay driver that connects the
INHIBIT line (ACC pin7) to a source of PTT which brings the inhibit
line LO in transmit.  PTT is coming from a four-stage sequencer which
is keyed by KEY OUT.

Since TRN5 was not outputting a logic=HI my INHIBIT line was holding
the K3 transmitter off.  I guess someday I will need to  repair the
logic ckt involved.

73, Ed - KL7UW
http://www.kl7uw.com
[hidden email]
"Kits made by KL7UW"

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html