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A broken K3

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David Olean

A broken K3

For all you tech gurus,

I am trying to fix an old K3 that belongs to my brother. He has serious
medical issues and I was hoping to fix his K3 so he can use it and be on
the air in between chemo treatments. He is very isolated and a working
ham rig would be a big help to him. I am not having much luck with tech
support with all the virus concerns and work disruptions. Here is what
is happening in his K3 SN: 378

No receive or transmit. I hear no band noise, just a bit of hiss with
the volume turned to max. He was in the middle of a QSO and it just
died. When you transmit, it acts like it is transmitting but there is no
output. The digital readout indicates a frequency and it changes as you
turn the big knob, but the K3 hears nothing and transmits nothing. If
you change bands the rig changes bands and all looks OK as to frequency
readout etc. I hear all the relays clicking, but no RX or TX anywhere.

I see a 8.23 MHz signal at the RXIF cable on the RF board (J-81) from
the KREF board. It is about 100 mv p to p.

I do not see any signal on the TXIF cable going to the RF board (J-65)
from KREF board.

I checked at Pin 2 on P73 (The synthesizer) for any RF output from the
VCO and I see nothing except some suspicious DC fluctuations that
amounts to a jump of maybe 100 mv. It looks random and not normal. I
should see several volts of RF here I think!

I do see the 49.380 MHz signal in the KREF board. (J1 & J2) That part is
working normally.

This is telling me that I have a synthesizer problem. Are there things
to check on the Synth board? Is there any typical failure mode that has
shown up? Are the boards repaired, or must I buy a new synthesizer
board? This is an original synthesizer board, not a new design K3S board.

I have been waiting for days to get any tech support response.

Any help would be appreciated.

73

Dave K1WHS

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David Olean

Re: A broken K3

You are right, Bill,

I have three K3s and the two oldest ones had old synths. I upgraded one
of them and kept one AS-IS so I could compare them. I do have two old
synthesizers. If worse comes to worse, I can plug one in and then I
think I need to do some form of synthesizer calibration . It has been so
long, I forgot! I did want to see if I could fix this one.

Dave K1WHS

On 3/24/2020 5:17 PM, Bill Steffey NY9H wrote:

> from looking at your pictures on QRZ it looks like you also have a
> k3... I would imagine you upgraded the synth boards ????
>
> yes??
>
>
>
> bill
>
> On 3/24/2020 12:57 PM, David Olean wrote:
>> For all you tech gurus,
>>
>> I am trying to fix an old K3 that belongs to my brother. He has
>> serious medical issues and I was hoping to fix his K3 so he can use
>> it and be on the air in between chemo treatments. He is very
>> isolated and a working ham rig would be a big help to him. I am not
>> having much luck with tech support with all the virus concerns and
>> work disruptions. Here is what is happening in his K3 SN: 378
>>
>> No receive or transmit. I hear no band noise, just a bit of hiss with
>> the volume turned to max. He was in the middle of a QSO and it just
>> died. When you transmit, it acts like it is transmitting but there is
>> no output. The digital readout indicates a frequency and it changes
>> as you turn the big knob, but the K3 hears nothing and transmits
>> nothing. If you change bands the rig changes bands and all looks OK
>> as to frequency readout etc. I hear all the relays clicking, but no
>> RX or TX anywhere.
>>
>> I see a 8.23 MHz signal at the RXIF cable on the RF board (J-81)
>> from the KREF board. It is about 100 mv p to p.
>>
>> I do not see any signal on the TXIF cable going to the RF board
>> (J-65) from KREF board.
>>
>> I checked at Pin 2 on P73 (The synthesizer) for any RF output from
>> the VCO and I see nothing except some suspicious DC fluctuations that
>> amounts to a jump of maybe 100 mv. It looks random and not normal. I
>> should see several volts of RF here I think!
>>
>> I do see the 49.380 MHz signal in the KREF board. (J1 & J2) That part
>> is working normally.
>>
>> This is telling me that I have a synthesizer problem. Are there
>> things to check on the Synth board? Is there any typical failure
>> mode that has shown up? Are the boards repaired, or must I buy a new
>> synthesizer board? This is an original synthesizer board, not a new
>> design K3S board.
>>
>> I have been waiting for days to get any tech support response.
>>
>> Any help would be appreciated.
>>
>> 73
>>
>> Dave K1WHS
>>
>>
>> ______________________________________________________________
>> 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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David Olean

Re: A broken K3

In reply to this post by David Olean

Thanks to all who offered an old style synthesizer. That is great. You
folks are the greatest (of course!) I actually have two old synths here,
so I can swap it out if it comes to that. I was just looking for
troubleshooting advice at the board level with the existing
synthesizer. I might want to keep my two old KSYNs intact as I may need
them in the future. Who knows? It is nice to know there are many folks
willing to help!

Thanks so much to all who responded. One thing I did not mention is
that I get a "HI RFI" error message at times when I key the radio. It
makes me wonder if there is something else wrong.

Dave K1WHS

On 3/24/2020 5:38 PM, w4sc wrote:

>
> Dave,
>
> I think I have a 1^st Gen Synthesizer (KSYN3) from when I upgraded
> to the KSYN3A. I’ll look….
>
> I’ll ship N/C if you can use
>
> 73 de Ben W4SC
>
> Sent from Mail <https://go.microsoft.com/fwlink/?LinkId=550986> for
> Windows 10
>

Don Wilhelm

Re: A broken K3

Dave,

HI RFI means the sensor on the RX antenna input is seeing a high level
of RF. If you are operating into an antenna, switch to a dummy load
while you are troubleshooting. It just might be a quirk of your setup,
and if you have no RX Antenna connected, it could be a troubleshooting
tool for you.

73,
Don W3FPR

On 3/24/2020 2:02 PM, David Olean wrote:
>
> Thanks so much to all who responded. One thing I did not mention is
> that I get a "HI RFI" error message at times when I key the radio. It
> makes me wonder if there is something else wrong.
>
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Wilson Lamb

A broken K3

In reply to this post by David Olean

Why wouldn't you change the synth?
I wouldn't even think of troubleshooting such a complicated, but free, board!
A bad one will obviously shut down both RX and TX!
WL
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David Olean

Re: A broken K3

I swapped out the non working synthesizer with a good one I had removed
for an upgrade. The new one did not work either, so it is something
else. I tried calibrating both synthesizers and received an error
message ERROR 00044 on both of them. I have been trying to contact
Elecraft support, but have no joy there yet.

I guess I need to study the schematics some more. I must be missing a
voltage somewhere. I tried re seating the connectors on many of the
boards including the front panel. No luck there either, but I will try
again tomorrow and use some DE-OXIT.

73

Dave K1WHS

On 3/25/2020 2:14 AM, Wilson Lamb wrote:

> Why wouldn't you change the synth?
> I wouldn't even think of troubleshooting such a complicated, but free, board!
> A bad one will obviously shut down both RX and TX!
> WL
> ______________________________________________________________
> 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
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K9FD

Re: A broken K3

In reply to this post by Don Wilhelm

I recently had a Hi RFI alarm, I could not clear it,
ended up being the KIO3 board set had a problem, since I had a
new one on hand to upgrade to, installing it solved the HI RFI
problem.
Looking back it seems that my failure came from a lightning pulse,
not a strike but a nearby cloud to cloud and it burned out the ant
input on the KIO3..

Yours may be much different, just relating my problem with HI RFI.

73 Merv K9FD

> Dave,
>
> HI RFI means the sensor on the RX antenna input is seeing a high level
> of RF. If you are operating into an antenna, switch to a dummy load
> while you are troubleshooting. It just might be a quirk of your
> setup, and if you have no RX Antenna connected, it could be a
> troubleshooting tool for you.
>
> 73,
> Don W3FPR
>
> On 3/24/2020 2:02 PM, David Olean wrote:
>>
>> Thanks so much to all who responded. One thing I did not mention is
>> that I get a "HI RFI" error message at times when I key the radio.
>> It makes me wonder if there is something else wrong.
>>
> ______________________________________________________________
> 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]

David Olean

Re: A broken K3

Hi Merv,

The HI RFI message may be a different problem. I know it can relate to
blown PIN diodes. Been there Done that! I am seeing no RF coming out of
the synthesizer and that would cause my RX and TX problem. Thanks for
the hints though. I appreciate any and all comments.

Dave K1WHS

On 3/25/2020 3:35 AM, K9FD wrote:

> I recently had a Hi RFI alarm, I could not clear it,
> ended up being the KIO3 board set had a problem, since I had a
> new one on hand to upgrade to, installing it solved the HI RFI
> problem.
> Looking back it seems that my failure came from a lightning pulse,
> not a strike but a nearby cloud to cloud and it burned out the ant
> input on the KIO3..
>
> Yours may be much different, just relating my problem with HI RFI.
>
> 73 Merv K9FD
>
>> Dave,
>>
>> HI RFI means the sensor on the RX antenna input is seeing a high
>> level of RF. If you are operating into an antenna, switch to a dummy
>> load while you are troubleshooting. It just might be a quirk of your
>> setup, and if you have no RX Antenna connected, it could be a
>> troubleshooting tool for you.
>>
>> 73,
>> Don W3FPR
>>
>> On 3/24/2020 2:02 PM, David Olean wrote:
>>>
>>> Thanks so much to all who responded. One thing I did not mention is
>>> that I get a "HI RFI" error message at times when I key the radio.
>>> It makes me wonder if there is something else wrong.
>>>
>> ______________________________________________________________
>> 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]
>
> ______________________________________________________________
> 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]

Elecraft mailing list

Re: A broken K3

In reply to this post by David Olean

David;

Go back and re-read the message from Keith Trinity. Keith is one of the guys down in Watsonville and knows more about the K3 than just about anyone.

To put it another way, you were indeed contacted by Customer Support.

73!
Jack, W6FB

> On Mar 24, 2020, at 7:46 PM, David Olean <[hidden email]> wrote:
>
> I swapped out the non working synthesizer with a good one I had removed for an upgrade. The new one did not work either, so it is something else. I tried calibrating both synthesizers and received an error message ERROR 00044 on both of them. I have been trying to contact Elecraft support, but have no joy there yet.
>
> I guess I need to study the schematics some more. I must be missing a voltage somewhere. I tried re seating the connectors on many of the boards including the front panel. No luck there either, but I will try again tomorrow and use some DE-OXIT.
>
> 73
>
> Dave K1WHS
>
> On 3/25/2020 2:14 AM, Wilson Lamb wrote:
>> Why wouldn't you change the synth?
>> I wouldn't even think of troubleshooting such a complicated, but free, board!
>> A bad one will obviously shut down both RX and TX!
>> WL
>> ______________________________________________________________
>> 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]
> ______________________________________________________________
> 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]

David Olean

Re: A broken K3

Hello Jack, I have responded to Keith and am following his directions.
He had lots of good info for me to try, and I am grateful for that.

Dave, K1WHS

On 3/25/2020 5:48 AM, Jack Brindle wrote:

> David;
>
> Go back and re-read the message from Keith Trinity. Keith is one of the guys down in Watsonville and knows more about the K3 than just about anyone.
>
> To put it another way, you were indeed contacted by Customer Support.
>
> 73!
> Jack, W6FB
>
>
>> On Mar 24, 2020, at 7:46 PM, David Olean <[hidden email]> wrote:
>>
>> I swapped out the non working synthesizer with a good one I had removed for an upgrade. The new one did not work either, so it is something else. I tried calibrating both synthesizers and received an error message ERROR 00044 on both of them. I have been trying to contact Elecraft support, but have no joy there yet.
>>
>> I guess I need to study the schematics some more. I must be missing a voltage somewhere. I tried re seating the connectors on many of the boards including the front panel. No luck there either, but I will try again tomorrow and use some DE-OXIT.
>>
>> 73
>>
>> Dave K1WHS
>>
>> On 3/25/2020 2:14 AM, Wilson Lamb wrote:
>>> Why wouldn't you change the synth?
>>> I wouldn't even think of troubleshooting such a complicated, but free, board!
>>> A bad one will obviously shut down both RX and TX!
>>> WL
>>> ______________________________________________________________
>>> 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]
>> ______________________________________________________________
>> 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]

Martin Sole-3

Re: A broken K3

Hi David,

I had a couple of failures this past year on my early K3 s/n 298. It's
been updated with new synths and a new KRX3A plus it was updated some
years ago before I got it and has most of the factory mods, though not
the gold pins. If you search the archive here on my callsign you can see
what I posted. Briefly I had first a loss of TX and some months later a
loss of RX and TX.

Both faults were traced to 0.1uF decoupling capacitors on the K3REF
board going leaky and puling bias voltages down such that they would not
switch the various circuits/signals. In the first case it caused loss
of the TX bias voltage so the diode switching was not working. In the
second case it was causing loss of second L.O. injection which of course
made for a rather quiet receiver as well as no transmit.

Good luck, for sure you can fix it or get it fixed.

73
Martin, HS0ZED

On 25/03/2020 21:49, David Olean wrote:

> Hello Jack, I have responded to Keith and am following his directions.
> He had lots of good info for me to try, and I am grateful for that.
>
> Dave, K1WHS
>
> On 3/25/2020 5:48 AM, Jack Brindle wrote:
>> David;
>>
>> Go back and re-read the message from Keith Trinity. Keith is one of
>> the guys down in Watsonville and knows more about the K3 than just
>> about anyone.
>>
>> To put it another way, you were indeed contacted by Customer Support.
>>
>> 73!
>> Jack, W6FB
>>
>>
>>> On Mar 24, 2020, at 7:46 PM, David Olean <[hidden email]> wrote:
>>>
>>> I swapped out the non working synthesizer with a good one I had
>>> removed for an upgrade. The new one did not work either, so it is
>>> something else. I tried calibrating both synthesizers and received
>>> an error message ERROR 00044 on both of them. I have been trying to
>>> contact Elecraft support, but have no joy there yet.
>>>
>>> I guess I need to study the schematics some more. I must be missing
>>> a voltage somewhere. I tried re seating the connectors on many of
>>> the boards including the front panel. No luck there either, but I
>>> will try again tomorrow and use some DE-OXIT.
>>>
>>> 73
>>>
>>> Dave K1WHS
>>>
>>> On 3/25/2020 2:14 AM, Wilson Lamb wrote:
>>>> Why wouldn't you change the synth?
>>>> I wouldn't even think of troubleshooting such a complicated, but
>>>> free, board!
>>>> A bad one will obviously shut down both RX and TX!
>>>> WL
>>>> ______________________________________________________________
>>>> 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]
>>> ______________________________________________________________
>>> 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]
> ______________________________________________________________
> Elecraft mailing list
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> 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]