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[K3] Lost output power...

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Dave Van Wallaghen

[K3] Lost output power...

Hi all,

Before I contact service, I thought I might post my problem here in case
it is something fairly simple.

I returned from a 2.5 week vacation a couple of weeks ago and sat down
to do the firmware upgrade to my K3. I had my K3 powered off and
disconnected the antenna while away but it was still connected to a
serial hub, paddles, P3 etc. It powered up just fine and I have never
received any type of error message. After the firmware upgrade, I went
to perform the TX Gain Calibration and noticed there is no power output.
No matter what power level I set, I have no output either via the Tune
function or keying. In fact, hitting the ATU Tune button only displays
"- -" on the front panel. I can hear the relays go through their
routine, but it never displays the SWR.

I searched the archives and found a few who reported similar problems,
but only a couple of solutions and a few without any resolution. I've
ruled out all the settings things I could find i.e Test Mode, Tnx Inh is
set to off etc. I did remove the KPA3 and I/O board and inserted the
bypass connector and still the same result. I do have transverter
output, so it is something past that - I'm presuming in the LPA area.

I really don't know if I had power output before the firmware upgrade or
not as I just didn't think to try it especially without receiving any
kind of error message. And I'm pretty sure everything was working before
I left for Dayton.

Anyway, I just thought I'd ask here first before contacting service in
case it is a known problem I just didn't find on Nabble.

Thanks in advance & 73,
Dave W8FGU

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Dave Van Wallaghen

Re: [K3] Lost output power...

Thanks for all the replies. I will try these suggestions tomorrow
(working today) and post my results to the list for future reference. I
will try the heat test on the LPA finals and driver first as I have all
the panels off and it will be a quick way to find out if that is where
the problem lies (kind of leaning that way).

Fred, I read some of the same comments with regard to the firmware
reload. I did in fact reload it a couple of times but not with the same
power on/off/removal procedure you stated. If the LPA test is ok, I will
try the reload again using your sequence. I always turn the K3/P3 off
and then back on again after a load, but I have not tried the power
removal technique.

Thanks again guys and I hope to have some results early tomorrow morning.

73,
Dave W8FGU

On 6/18/2012 6:37 PM, Dave Van Wallaghen wrote:

> Hi all,
>
> Before I contact service, I thought I might post my problem here in case
> it is something fairly simple.
>
> I returned from a 2.5 week vacation a couple of weeks ago and sat down
> to do the firmware upgrade to my K3. I had my K3 powered off and
> disconnected the antenna while away but it was still connected to a
> serial hub, paddles, P3 etc. It powered up just fine and I have never
> received any type of error message. After the firmware upgrade, I went
> to perform the TX Gain Calibration and noticed there is no power output.
> No matter what power level I set, I have no output either via the Tune
> function or keying. In fact, hitting the ATU Tune button only displays
> "- -" on the front panel. I can hear the relays go through their
> routine, but it never displays the SWR.
>
> I searched the archives and found a few who reported similar problems,
> but only a couple of solutions and a few without any resolution. I've
> ruled out all the settings things I could find i.e Test Mode, Tnx Inh is
> set to off etc. I did remove the KPA3 and I/O board and inserted the
> bypass connector and still the same result. I do have transverter
> output, so it is something past that - I'm presuming in the LPA area.
>
> I really don't know if I had power output before the firmware upgrade or
> not as I just didn't think to try it especially without receiving any
> kind of error message. And I'm pretty sure everything was working before
> I left for Dayton.
>
> Anyway, I just thought I'd ask here first before contacting service in
> case it is a known problem I just didn't find on Nabble.
>
> Thanks in advance& 73,
> Dave W8FGU
>
> ______________________________________________________________
> 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
>

______________________________________________________________
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

Dave Van Wallaghen

Re: [K3] Lost output power...

Further info:

I sat down today and performed another firmware load per Fred's sequence
with no change. I then tested for any heat generation from the driver
and finals of the LPA module and could not detect any.

I dug out my old Tek 475A scope and did some signal tracing and verified
that I have appropriate RF coming into the LPA module (pin 3 on P71A) as
well as 12v coming in on pins 9 & 10 of P71B. I also have a logical HI
on the 7T line (pin 1 of P71A) during XMIT. I do not have RF coming out
on pin 1 of P71C.

I just emailed support with the same report, but I'm guessing my LPA is
shot. Anybody have any idea what that will cost?

Thanks again for all the suggestions. I think I have it narrowed down
pretty well now.

73,
Dave W8FGU

On 6/19/2012 9:13 AM, Dave Van Wallaghen wrote:

> Thanks for all the replies. I will try these suggestions tomorrow
> (working today) and post my results to the list for future reference. I
> will try the heat test on the LPA finals and driver first as I have all
> the panels off and it will be a quick way to find out if that is where
> the problem lies (kind of leaning that way).
>
> Fred, I read some of the same comments with regard to the firmware
> reload. I did in fact reload it a couple of times but not with the same
> power on/off/removal procedure you stated. If the LPA test is ok, I will
> try the reload again using your sequence. I always turn the K3/P3 off
> and then back on again after a load, but I have not tried the power
> removal technique.
>
> Thanks again guys and I hope to have some results early tomorrow morning.
>
> 73,
> Dave W8FGU
>
>
> On 6/18/2012 6:37 PM, Dave Van Wallaghen wrote:
>> Hi all,
>>
>> Before I contact service, I thought I might post my problem here in case
>> it is something fairly simple.
>>
>> I returned from a 2.5 week vacation a couple of weeks ago and sat down
>> to do the firmware upgrade to my K3. I had my K3 powered off and
>> disconnected the antenna while away but it was still connected to a
>> serial hub, paddles, P3 etc. It powered up just fine and I have never
>> received any type of error message. After the firmware upgrade, I went
>> to perform the TX Gain Calibration and noticed there is no power output.
>> No matter what power level I set, I have no output either via the Tune
>> function or keying. In fact, hitting the ATU Tune button only displays
>> "- -" on the front panel. I can hear the relays go through their
>> routine, but it never displays the SWR.
>>
>> I searched the archives and found a few who reported similar problems,
>> but only a couple of solutions and a few without any resolution. I've
>> ruled out all the settings things I could find i.e Test Mode, Tnx Inh is
>> set to off etc. I did remove the KPA3 and I/O board and inserted the
>> bypass connector and still the same result. I do have transverter
>> output, so it is something past that - I'm presuming in the LPA area.
>>
>> I really don't know if I had power output before the firmware upgrade or
>> not as I just didn't think to try it especially without receiving any
>> kind of error message. And I'm pretty sure everything was working before
>> I left for Dayton.
>>
>> Anyway, I just thought I'd ask here first before contacting service in
>> case it is a known problem I just didn't find on Nabble.
>>
>> Thanks in advance& 73,
>> Dave W8FGU
>>
>> ______________________________________________________________
>> 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
>>
> ______________________________________________________________
> 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
>