K3 with subrx - intermittent main RX problem and pwr out

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K3 with subrx - intermittent main RX problem and pwr out

la3rk
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
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Re: K3 with subrx - intermittent main RX problem and pwr out

Don Wilhelm
Olaf,

The relays used by Elecraft are quite reliable, so I suspect that is not
a reasonable source of the problem.  In more than 12 years of repairing
the Elecraft legacy gear (more than 1200 repairs), I have had to replace
only a small handful of relays due to failure.  I have replaced several
where the builder has distorted the case with a soldering iron.

I would double and triple check the SUBIN and SUBOUT connectors.  A
connector failure is much more likely than a relay failure.

You might contact K3support to see if they have encountered a situation
like yours before.

73,
Don W3FPR

On 5/4/2017 3:31 AM, la3rk wrote:
> 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.
>
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Re: K3 with subrx - intermittent main RX problem and pwr out

Guy Olinger K2AV
Must underscore what Don said. Busted BNC connector/coax wiring is so
very common. If they were hand-done with soldering iron and NOT RG400
coax (teflon, won't melt) or were not crimped with specific tool
required for the specific connector and specific coax, they are more
likely to go bad over time. This is because BNC connections get moved
and moved and moved....

The basic rule is never open up the Elecraft case until braine phartes
and *all* external connections are *ruled out*, and in extreme cases
the manual is read.  Save yourself tons of time in the long run.

73, Guy K2AV

On Thu, May 4, 2017 at 9:46 AM, Don Wilhelm <[hidden email]> wrote:

> Olaf,
>
> The relays used by Elecraft are quite reliable, so I suspect that is not a
> reasonable source of the problem.  In more than 12 years of repairing the
> Elecraft legacy gear (more than 1200 repairs), I have had to replace only a
> small handful of relays due to failure.  I have replaced several where the
> builder has distorted the case with a soldering iron.
>
> I would double and triple check the SUBIN and SUBOUT connectors.  A
> connector failure is much more likely than a relay failure.
>
> You might contact K3support to see if they have encountered a situation like
> yours before.
>
> 73,
> Don W3FPR
>
> On 5/4/2017 3:31 AM, la3rk wrote:
>>
>> 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.
>>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
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> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]
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Re: K3 with subrx - intermittent main RX problem and pwr out

Victor Rosenthal 4X6GP
In reply to this post by Don Wilhelm
Well, I had a relay fail on my KAT3 board. I don't remember which one.
Elecraft sent me a replacement. It wasn't hard to replace, but it happens.

73,
Victor, 4X6GP
Rehovot, Israel
Formerly K2VCO
http://www.qsl.net/k2vco/

On 4 May 2017 16:46, Don Wilhelm wrote:

> Olaf,
>
> The relays used by Elecraft are quite reliable, so I suspect that is not
> a reasonable source of the problem.  In more than 12 years of repairing
> the Elecraft legacy gear (more than 1200 repairs), I have had to replace
> only a small handful of relays due to failure.  I have replaced several
> where the builder has distorted the case with a soldering iron.
>
> I would double and triple check the SUBIN and SUBOUT connectors.  A
> connector failure is much more likely than a relay failure.
>
> You might contact K3support to see if they have encountered a situation
> like yours before.
>
> 73,
> Don W3FPR
>
> On 5/4/2017 3:31 AM, la3rk wrote:
>> 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.
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Re: K3 with subrx - intermittent main RX problem and pwr out

briancom
In reply to this post by Don Wilhelm
Also make sure TMP connectors to and from synthesizer/KREF/Subrx boards
are secure.

Brian/K3KO

On 5/4/2017 13:46 PM, Don Wilhelm wrote:

> Olaf,
>
> The relays used by Elecraft are quite reliable, so I suspect that is not
> a reasonable source of the problem.  In more than 12 years of repairing
> the Elecraft legacy gear (more than 1200 repairs), I have had to replace
> only a small handful of relays due to failure.  I have replaced several
> where the builder has distorted the case with a soldering iron.
>
> I would double and triple check the SUBIN and SUBOUT connectors.  A
> connector failure is much more likely than a relay failure.
>
> You might contact K3support to see if they have encountered a situation
> like yours before.
>
> 73,
> Don W3FPR
>
> On 5/4/2017 3:31 AM, la3rk wrote:
>> 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.
>>
> ______________________________________________________________
> 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
> Message delivered to [hidden email]
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Re: K3 with subrx - intermittent main RX problem and pwr out

Alan. G4GNX
In reply to this post by Victor Rosenthal 4X6GP
FWIW we thought that a relay was failing on our club's KAT500. I bought a
new one from Elecraft and replaced it without thinking about it. They're
quite cheap and it wasn't worth chancing an intermittent relay.
Whilst I was re-assembling the tuner, I discovered that the tag washer
connecting Ant 1 to its screw terminal had developed a dry joint, which was
the real cause of the intermittency. I don't know whether it was a
manufacturing fault or someone had been heavy handed when assembling it.

It would be worth checking soldered joints and other connections before
replacing a relay. You may need to use a magnifying glass as it may not show
up on a meter test. Another thing to try is what we used to do as service
technicians; use an aerosol freezer spray in small areas around the
suspected area and possibly a hair dryer on a warm setting (not hot) and
observe for changes under test.

73,

Alan. G4GNX

-----Original Message-----
From: Victor Rosenthal 4X6GP
Sent: Thursday, May 4, 2017 3:07 PM
To: [hidden email]
Subject: Re: [Elecraft] K3 with subrx - intermittent main RX problem and pwr
out

Well, I had a relay fail on my KAT3 board. I don't remember which one.
Elecraft sent me a replacement. It wasn't hard to replace, but it happens.

73,
Victor, 4X6GP
Rehovot, Israel
Formerly K2VCO
http://www.qsl.net/k2vco/

On 4 May 2017 16:46, Don Wilhelm wrote:

> Olaf,
>
> The relays used by Elecraft are quite reliable, so I suspect that is not
> a reasonable source of the problem.  In more than 12 years of repairing
> the Elecraft legacy gear (more than 1200 repairs), I have had to replace
> only a small handful of relays due to failure.  I have replaced several
> where the builder has distorted the case with a soldering iron.
>
> I would double and triple check the SUBIN and SUBOUT connectors.  A
> connector failure is much more likely than a relay failure.
>
> You might contact K3support to see if they have encountered a situation
> like yours before.
>
> 73,
> Don W3FPR
>
> On 5/4/2017 3:31 AM, la3rk wrote:
>> 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.

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Re: K3 with subrx - intermittent main RX problem and pwr out

Matt Zilmer-3
Sorry to be thick....  Is a dry joint same as a cold joint?

Thanks and 73,

matt W6NIA


On 5/4/2017 9:12 AM, Alan. G4GNX wrote:

> FWIW we thought that a relay was failing on our club's KAT500. I
> bought a new one from Elecraft and replaced it without thinking about
> it. They're quite cheap and it wasn't worth chancing an intermittent
> relay.
> Whilst I was re-assembling the tuner, I discovered that the tag washer
> connecting Ant 1 to its screw terminal had developed a dry joint,
> which was the real cause of the intermittency. I don't know whether it
> was a manufacturing fault or someone had been heavy handed when
> assembling it.
>
> It would be worth checking soldered joints and other connections
> before replacing a relay. You may need to use a magnifying glass as it
> may not show up on a meter test. Another thing to try is what we used
> to do as service technicians; use an aerosol freezer spray in small
> areas around the suspected area and possibly a hair dryer on a warm
> setting (not hot) and observe for changes under test.
>
> 73,
>
> Alan. G4GNX
>
> -----Original Message----- From: Victor Rosenthal 4X6GP
> Sent: Thursday, May 4, 2017 3:07 PM
> To: [hidden email]
> Subject: Re: [Elecraft] K3 with subrx - intermittent main RX problem
> and pwr out
>
> Well, I had a relay fail on my KAT3 board. I don't remember which one.
> Elecraft sent me a replacement. It wasn't hard to replace, but it
> happens.
>
> 73,
> Victor, 4X6GP
> Rehovot, Israel
> Formerly K2VCO
> http://www.qsl.net/k2vco/
>
> On 4 May 2017 16:46, Don Wilhelm wrote:
>> Olaf,
>>
>> The relays used by Elecraft are quite reliable, so I suspect that is not
>> a reasonable source of the problem.  In more than 12 years of repairing
>> the Elecraft legacy gear (more than 1200 repairs), I have had to replace
>> only a small handful of relays due to failure.  I have replaced several
>> where the builder has distorted the case with a soldering iron.
>>
>> I would double and triple check the SUBIN and SUBOUT connectors.  A
>> connector failure is much more likely than a relay failure.
>>
>> You might contact K3support to see if they have encountered a situation
>> like yours before.
>>
>> 73,
>> Don W3FPR
>>
>> On 5/4/2017 3:31 AM, la3rk wrote:
>>> 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.
>
> ______________________________________________________________
> 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
> Message delivered to [hidden email]

--
"A delay is better than a disaster."
-- unknown

Matt Zilmer, W6NIA
[Shiraz]

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Re: K3 with subrx - intermittent main RX problem and pwr out

Grant Youngman-2
In reply to this post by la3rk
I had this happen with the 2M module, too.  What I do now with these is try to support the little teflon insulator in the socket from the rear with a small flat-blade screwdriver — at least the ones I get to that way.

Took a while to figure out what the problem was, since everything looks “normal" from the outside …


> On May 4, 2017, at 1:05 PM, Ron D'Eau Claire <[hidden email]> wrote:
>
> 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.
> ...
>
> 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.
>
>

Grant NQ5T
K3 #2091, KX3 #8342



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Re: K3 with subrx - intermittent main RX problem and pwr out

k6dgw
In reply to this post by Matt Zilmer-3
"Two countries separated by a common language."  I believe "tag washer"
is a "solder lug" on our side of the Atlantic.  I think Alan might mean
the screw connection on that lug becoming intermittent due to oxidation
and/or inadequate tightening.  Generally speaking, cold solder joints
are "cold" immediately after the soldering process and don't develop
later, although I've seen that happen due to very minor extended
vibration of the joint.

73,

Fred ("Skip") K6DGW
Sparks NV USA
Washoe County DM09dn

On 5/4/2017 9:43 AM, Matt Zilmer wrote:

> Sorry to be thick....  Is a dry joint same as a cold joint?
>
> Thanks and 73,
>
> matt W6NIA
>
>
> On 5/4/2017 9:12 AM, Alan. G4GNX wrote:
>> FWIW we thought that a relay was failing on our club's KAT500. I
>> bought a new one from Elecraft and replaced it without thinking about
>> it. They're quite cheap and it wasn't worth chancing an intermittent
>> relay.
>> Whilst I was re-assembling the tuner, I discovered that the tag
>> washer connecting Ant 1 to its screw terminal had developed a dry
>> joint, which was the real cause of the intermittency. I don't know
>> whether it was a manufacturing fault or someone had been heavy handed
>> when assembling it.
>>
>> It would be worth checking soldered joints and other connections
>> before replacing a relay. You may need to use a magnifying glass as
>> it may not show up on a meter test. Another thing to try is what we
>> used to do as service technicians; use an aerosol freezer spray in
>> small areas around the suspected area and possibly a hair dryer on a
>> warm setting (not hot) and observe for changes under test.
>>
>> 73,
>>
>> Alan. G4GNX

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Re: K3 with subrx - intermittent main RX problem and pwr out

Alan. G4GNX
In reply to this post by Matt Zilmer-3
Matt.

You are not at all thick. We all have to learn somewhere. The only time you
could be considered thick is if you never asked the question. :-)

The wiki/dictionary description of dry and cold joints describes slightly
different observable effects but to all intents and purposes a dry or cold
solder joint will produce the same result. Both usually result in a breakage
of the bond between the two components that are soldered. The simple
solution is to re-solder the joint using sufficient heat to melt the old
solder. You can either remove the old solder and apply new solder, or you
can add a little flux when you heat the joint. I would prefer to remove the
old solder and replace it with new flux cored solder. If you haven't done
much of this type of work, probably the easiest way to remove old solder is
with some "solder wick" which you can purchase for pennies on eBay. Place
the wick braid on the solder to be removed and apply a hot soldering iron.
The wick will soak up the solder and if it doesn't remove it all first time,
re-apply the wick a 2nd or 3rd time.

One thing you ABSOLUTELY MUST do before you start ANY work inside your rig,
is to observe ANTI-STATIC precautions. Use a wrist strap specially made for
the job and preferably use an anti-static mat. DO NOT EVER connect yourself
directly to any anti-static ground source - you could DIE!

73,

Alan. G4GNX

-----Original Message-----
From: Matt Zilmer
Sent: Thursday, May 4, 2017 5:43 PM
To: [hidden email]
Subject: Re: [Elecraft] K3 with subrx - intermittent main RX problem and pwr
out

Sorry to be thick....  Is a dry joint same as a cold joint?

Thanks and 73,

matt W6NIA

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Re: K3 with subrx - intermittent main RX problem and pwr out

Alan. G4GNX
In reply to this post by k6dgw
Solder lug/solder tag/tag washer all the same thing. :-)

Perhaps instead of dry joint I should have said "broken joint". The bond
between the solder lug and the connecting wire had become broken,
resulting in the effect of a dry joint. This could have been caused by
someone being over enthusiastic with a screwdriver, resulting in the lug
being put under great strain by the securing screw being turned and
breaking the solder joint by force rather than by movement whilst the
solder was cooling at manufacture.

73,

Alan. G4GNX

On 04/05/2017 18:28, Fred Jensen wrote:

> "Two countries separated by a common language."  I believe "tag
> washer" is a "solder lug" on our side of the Atlantic.  I think Alan
> might mean the screw connection on that lug becoming intermittent due
> to oxidation and/or inadequate tightening.  Generally speaking, cold
> solder joints are "cold" immediately after the soldering process and
> don't develop later, although I've seen that happen due to very minor
> extended vibration of the joint.
>
> 73,
>
> Fred ("Skip") K6DGW
> Sparks NV USA
> Washoe County DM09dn

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Re: K3 with subrx - intermittent main RX problem and pwr out

Bill K9YEQ
In reply to this post by Matt Zilmer-3
Matt, a difference in the language.  I would take them to be the same.

73,
Bill
K9YEQ

-----Original Message-----
From: Elecraft [mailto:[hidden email]] On Behalf Of Matt Zilmer
Sent: Thursday, May 4, 2017 11:44 AM
To: [hidden email]
Subject: Re: [Elecraft] K3 with subrx - intermittent main RX problem and pwr out

Sorry to be thick....  Is a dry joint same as a cold joint?

Thanks and 73,

matt W6NIA


On 5/4/2017 9:12 AM, Alan. G4GNX wrote:

> FWIW we thought that a relay was failing on our club's KAT500. I
> bought a new one from Elecraft and replaced it without thinking about
> it. They're quite cheap and it wasn't worth chancing an intermittent
> relay.
> Whilst I was re-assembling the tuner, I discovered that the tag washer
> connecting Ant 1 to its screw terminal had developed a dry joint,
> which was the real cause of the intermittency. I don't know whether it
> was a manufacturing fault or someone had been heavy handed when
> assembling it.
>
> It would be worth checking soldered joints and other connections
> before replacing a relay. You may need to use a magnifying glass as it
> may not show up on a meter test. Another thing to try is what we used
> to do as service technicians; use an aerosol freezer spray in small
> areas around the suspected area and possibly a hair dryer on a warm
> setting (not hot) and observe for changes under test.
>
> 73,
>
> Alan. G4GNX
>
> -----Original Message----- From: Victor Rosenthal 4X6GP
> Sent: Thursday, May 4, 2017 3:07 PM
> To: [hidden email]
> Subject: Re: [Elecraft] K3 with subrx - intermittent main RX problem
> and pwr out
>
> Well, I had a relay fail on my KAT3 board. I don't remember which one.
> Elecraft sent me a replacement. It wasn't hard to replace, but it
> happens.
>
> 73,
> Victor, 4X6GP
> Rehovot, Israel
> Formerly K2VCO
> http://www.qsl.net/k2vco/
>
> On 4 May 2017 16:46, Don Wilhelm wrote:
>> Olaf,
>>
>> The relays used by Elecraft are quite reliable, so I suspect that is
>> not a reasonable source of the problem.  In more than 12 years of
>> repairing the Elecraft legacy gear (more than 1200 repairs), I have
>> had to replace only a small handful of relays due to failure.  I have
>> replaced several where the builder has distorted the case with a soldering iron.
>>
>> I would double and triple check the SUBIN and SUBOUT connectors.  A
>> connector failure is much more likely than a relay failure.
>>
>> You might contact K3support to see if they have encountered a
>> situation like yours before.
>>
>> 73,
>> Don W3FPR
>>
>> On 5/4/2017 3:31 AM, la3rk wrote:
>>> 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.
>
> ______________________________________________________________
> 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 Message delivered to
> [hidden email]

--
"A delay is better than a disaster."
-- unknown

Matt Zilmer, W6NIA
[Shiraz]

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Re: K3 with subrx - intermittent main RX problem and pwr out

Matt Zilmer-3
That's what seemed like a normal language difference to me too.  Thanks,
Bill.

73,

matt W6NIA


On 5/4/2017 7:11 PM, Bill Johnson wrote:

> Matt, a difference in the language.  I would take them to be the same.
>
> 73,
> Bill
> K9YEQ
>
> -----Original Message-----
> From: Elecraft [mailto:[hidden email]] On Behalf Of Matt Zilmer
> Sent: Thursday, May 4, 2017 11:44 AM
> To: [hidden email]
> Subject: Re: [Elecraft] K3 with subrx - intermittent main RX problem and pwr out
>
> Sorry to be thick....  Is a dry joint same as a cold joint?
>
> Thanks and 73,
>
> matt W6NIA
>
>
> On 5/4/2017 9:12 AM, Alan. G4GNX wrote:
>> FWIW we thought that a relay was failing on our club's KAT500. I
>> bought a new one from Elecraft and replaced it without thinking about
>> it. They're quite cheap and it wasn't worth chancing an intermittent
>> relay.
>> Whilst I was re-assembling the tuner, I discovered that the tag washer
>> connecting Ant 1 to its screw terminal had developed a dry joint,
>> which was the real cause of the intermittency. I don't know whether it
>> was a manufacturing fault or someone had been heavy handed when
>> assembling it.
>>
>> It would be worth checking soldered joints and other connections
>> before replacing a relay. You may need to use a magnifying glass as it
>> may not show up on a meter test. Another thing to try is what we used
>> to do as service technicians; use an aerosol freezer spray in small
>> areas around the suspected area and possibly a hair dryer on a warm
>> setting (not hot) and observe for changes under test.
>>
>> 73,
>>
>> Alan. G4GNX
>>
>> -----Original Message----- From: Victor Rosenthal 4X6GP
>> Sent: Thursday, May 4, 2017 3:07 PM
>> To: [hidden email]
>> Subject: Re: [Elecraft] K3 with subrx - intermittent main RX problem
>> and pwr out
>>
>> Well, I had a relay fail on my KAT3 board. I don't remember which one.
>> Elecraft sent me a replacement. It wasn't hard to replace, but it
>> happens.
>>
>> 73,
>> Victor, 4X6GP
>> Rehovot, Israel
>> Formerly K2VCO
>> http://www.qsl.net/k2vco/
>>
>> On 4 May 2017 16:46, Don Wilhelm wrote:
>>> Olaf,
>>>
>>> The relays used by Elecraft are quite reliable, so I suspect that is
>>> not a reasonable source of the problem.  In more than 12 years of
>>> repairing the Elecraft legacy gear (more than 1200 repairs), I have
>>> had to replace only a small handful of relays due to failure.  I have
>>> replaced several where the builder has distorted the case with a soldering iron.
>>>
>>> I would double and triple check the SUBIN and SUBOUT connectors.  A
>>> connector failure is much more likely than a relay failure.
>>>
>>> You might contact K3support to see if they have encountered a
>>> situation like yours before.
>>>
>>> 73,
>>> Don W3FPR
>>>
>>> On 5/4/2017 3:31 AM, la3rk wrote:
>>>> 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.
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> --
> "A delay is better than a disaster."
> -- unknown
>
> Matt Zilmer, W6NIA
> [Shiraz]
>
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--
"A delay is better than a disaster."
-- unknown

Matt Zilmer, W6NIA
[Shiraz]

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Re: K3 with subrx - intermittent main RX problem and pwr out

la3rk
In reply to this post by la3rk
Thanks to all who responded. Checked and realigned all connectors, no apparent errors, all male pins in place, connectors firmly seated.

Removed KRX3 and SUBIN/OUT module, reinstalled and reconnected. Similar advice received both from group and from Elecraft support.

Still same problem, main rx uses signal. According to info from German ham, he has had same problem and it was traced to faulty pin diode on SUBIN/OUT module.

It is kind of amusing how a technical subject like this turns into differences in languages use between USA and England. It would be nice if posters keep to original subject and not stray off in a completely different direction. Of 22 postings just 3 or 4 of them was on the original subject and problem.

I am fairly certain that the problem is located within the SUBIN/OUT module, but will check with Elecraft support. The easiest will be to change the whole module, it is just a relay, some diodes and two small RF transformers.

73 de Olaf - LA3RK
73 de LA3RK Olaf