[Elecraft] K3 with subrx - intermittent main RX problem and pwr out

[Ron D'Eau Claire]

An intermittent or open circuit problem that has occurred on occasion is
caused by misaligning TMP male and pressing it too hard into the socket.
What can happen is that the male pin hits the metal edge of the female
socket inside the connector and actually pushes the metal socket out of its
housing. The result is that the female socket edge is just resting against
the male pin rather than having the male pin inside the socket even though
the connector appears properly mated. This results in an intermittent
contact. 

The solution is to visually inspect the various TMP connectors on the KRX3
board as well as those on the KREF3 and Aux KSYN3 board. Looking into the
socket you should see the metal receptacle inside the white plastic
(Teflon?). IF all you can see is plastic, you may have pushed the metal
socket back out of the connector. 

You can get access to the back of the connector and push the metal
receptacle back in place but it will likely tend to bend again more easily
now that it has been pushed out of place once. Be especially careful of it
when plugging in the TMP cable.

73, Ron AC7AC 

-----Original Message-----
From: Elecraft [mailto:elecraft-bounces at mailman.qth.net] On Behalf Of la3rk
Sent: Thursday, May 4, 2017 12:32 AM
To: elecraft at mailman.qth.net
Subject: [Elecraft] K3 with subrx - intermittent main RX problem and pwr out

I have a K3 approx 8 years old. Fully equipped with subrx, 100W PA, antenna
tuner and in/out module.

When I connect the subrx, the main rx sometimes loses signal and at the same
time power out goes to zero.

Looking at the diagrams, I suspect there is an intermittent contact problem
in relay K1 shown on the SUBIN schematic. This relay is responsible for
sending antenna signals to the splitter when using the subrx and also
connects the splitter output back to the main rx. The same contacts on the
relay is also a path for the low level tx signal. An intermittent contact on
this relay and particularly contacts 3-4 could explain the behaviour I see.

Has anybody experience relay failures and if yes have they managed to change
out the relay?

Sending the K3 back to Elecraft is not a preferred option as shipping
charges to/from Norway will be fairly expensive.

Regards
LA3RK - Olaf Devik



-----
73 de LA3RK Olaf
--
View this message in context:
http://elecraft.365791.n2.nabble.com/K3-with-subrx-intermittent-main-RX-prob
lem-and-pwr-out-tp7630294.html
Sent from the Elecraft mailing list archive at Nabble.com.
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html Message
delivered to ron at elecraft.com