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K2 is dead?

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David Perrin

K2 is dead?

Hi-

Two questions?

After 18 years my K2 doesn’t turn on. I did it. I must have incorrectly wired the Serial cable. When it got plugged in - that did it.

There is power thru the Power button. With the radio disassembled to the main pc board, (sans everything that can plug into the main board) and power applied thru the 1/8” coaxial power connector power doesn’t seem to get beyond that.

I am not in a place where I can get more parts out on the bench, nor the equipment except for a cheap digital Voltmeter.

Question 1: Is there someone in the central Florida area who knows this radio and can shed some light on my problem?

Question 2: Is there someone in central Florida who repairs the K2?

Thanks for reading.

73 de Dave

[hidden email]

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Don Wilhelm

Re: K2 is dead?

David,

There are several possibilities.
While it is possible that the "serial" cable may have been the the
problem, that could have damaged the KIO2 (or KPA100), but it could also
have damaged the MCU (U6) on the control board.

Did it go into transmit with no load? If so, it may be that Q7 and Q8
have been damaged. Check the resistance from the collector to ground.
It should start out at about 2k ohms and increase in resistance as the
electrolytics charge. If it is substantially less than that, the PA
transistors may have been damaged - that will trip the internal
resettable fuse (F1).
To remove 12v power from the PA transistors, you can remove them (do
that if the resistance check reveals them to be shorted), or you can
remove transformer T3.
After removing 12v from the PA transistors, see if the K2 powers on.

I don't know of anyone who is skilled in troubleshooting the K2 in
central FL, but someone may volunteer.

If you remove the PA transistors and do not have adequate desoldering
ability, clip the leads at the transistor bodies and remove the leads
one at a time. Clean up with solder wick and if solder remains in the
holes, heat the pads and push the solder out with a wooden toothpick.
Replace the PA transistors with the K2PAKIT from Elecraft - it has
matched PA transistors. I can give you some tests to check with the PA
transistors out to check whether transistors Q11 and Q13 are OK (they
are included with the K2PAKIT).

73,
Don W3FPR

On 2/19/2018 10:20 AM, David Perrin wrote:

> Hi-
>
> Two questions?
>
> After 18 years my K2 doesn’t turn on. I did it. I must have incorrectly wired the Serial cable. When it got plugged in - that did it.
>
> There is power thru the Power button. With the radio disassembled to the main pc board, (sans everything that can plug into the main board) and power applied thru the 1/8” coaxial power connector power doesn’t seem to get beyond that.
>
> I am not in a place where I can get more parts out on the bench, nor the equipment except for a cheap digital Voltmeter.
>
> Question 1: Is there someone in the central Florida area who knows this radio and can shed some light on my problem?
>
> Question 2: Is there someone in central Florida who repairs the K2?
>
> Thanks for reading.
>
> 73 de Dave
>
> [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]
>

Bill K9YEQ

Re: K2 is dead?

Dave, my suggestion: send it Don who is a fantastic expert. He is very reasonalble in his fees. While I am technically competent, and have the equipment, he is natural at it. I have to work at it, because unlike Don, don't do it day to day. I have sent equipment to him and it is done in no time. If you have time to do your own work, then give that a shot. For me, life it too short.

73,
Bill
K9YEQ

-----Original Message-----
From: [hidden email] [mailto:[hidden email]] On Behalf Of Don Wilhelm
Sent: Monday, February 19, 2018 6:28 PM
To: David Perrin <[hidden email]>; Elecraft <[hidden email]>
Subject: Re: [Elecraft] K2 is dead?

David,[Bill] n

There are several possibilities.
While it is possible that the "serial" cable may have been the the problem, that could have damaged the KIO2 (or KPA100), but it could also have damaged the MCU (U6) on the control board.

Did it go into transmit with no load? If so, it may be that Q7 and Q8 have been damaged. Check the resistance from the collector to ground.
It should start out at about 2k ohms and increase in resistance as the electrolytics charge. If it is substantially less than that, the PA transistors may have been damaged - that will trip the internal resettable fuse (F1).
To remove 12v power from the PA transistors, you can remove them (do that if the resistance check reveals them to be shorted), or you can remove transformer T3.
After removing 12v from the PA transistors, see if the K2 powers on.

I don't know of anyone who is skilled in troubleshooting the K2 in central FL, but someone may volunteer.

If you remove the PA transistors and do not have adequate desoldering ability, clip the leads at the transistor bodies and remove the leads one at a time. Clean up with solder wick and if solder remains in the holes, heat the pads and push the solder out with a wooden toothpick.
Replace the PA transistors with the K2PAKIT from Elecraft - it has matched PA transistors. I can give you some tests to check with the PA transistors out to check whether transistors Q11 and Q13 are OK (they are included with the K2PAKIT).

73,
Don W3FPR

On 2/19/2018 10:20 AM, David Perrin wrote:

> Hi-
>
> Two questions?
>
> After 18 years my K2 doesn’t turn on. I did it. I must have incorrectly wired the Serial cable. When it got plugged in - that did it.
>
> There is power thru the Power button. With the radio disassembled to the main pc board, (sans everything that can plug into the main board) and power applied thru the 1/8” coaxial power connector power doesn’t seem to get beyond that.
>
> I am not in a place where I can get more parts out on the bench, nor the equipment except for a cheap digital Voltmeter.
>
> Question 1: Is there someone in the central Florida area who knows this radio and can shed some light on my problem?
>
> Question 2: Is there someone in central Florida who repairs the K2?
>
> Thanks for reading.
>
> 73 de Dave
>
> [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
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]

Ken G Kopp

Re: K2 is dead?

I'll add my enthusiastic endorsement for Don, W3FPR. He's prompt and
reasonable.

73!

Ken - K0PP

On Feb 19, 2018 18:50, "Bill Johnson" <[hidden email]> wrote:

> Dave, my suggestion: send it Don who is a fantastic expert. He is very
> reasonalble in his fees. While I am technically competent, and have the
> equipment, he is natural at it. I have to work at it, because unlike Don,
> don't do it day to day. I have sent equipment to him and it is done in no
> time. If you have time to do your own work, then give that a shot. For
> me, life it too short.
>
>
> 73,
> Bill
> K9YEQ
>
>
>
> -----Original Message-----
> From: [hidden email] [mailto:elecraft-bounces@
> mailman.qth.net] On Behalf Of Don Wilhelm
> Sent: Monday, February 19, 2018 6:28 PM
> To: David Perrin <[hidden email]>; Elecraft <[hidden email]>
> Subject: Re: [Elecraft] K2 is dead?
>
> David,[Bill] n
>
> There are several possibilities.
> While it is possible that the "serial" cable may have been the the
> problem, that could have damaged the KIO2 (or KPA100), but it could also
> have damaged the MCU (U6) on the control board.
>
> Did it go into transmit with no load? If so, it may be that Q7 and Q8
> have been damaged. Check the resistance from the collector to ground.
> It should start out at about 2k ohms and increase in resistance as the
> electrolytics charge. If it is substantially less than that, the PA
> transistors may have been damaged - that will trip the internal resettable
> fuse (F1).
> To remove 12v power from the PA transistors, you can remove them (do that
> if the resistance check reveals them to be shorted), or you can remove
> transformer T3.
> After removing 12v from the PA transistors, see if the K2 powers on.
>
> I don't know of anyone who is skilled in troubleshooting the K2 in central
> FL, but someone may volunteer.
>
> If you remove the PA transistors and do not have adequate desoldering
> ability, clip the leads at the transistor bodies and remove the leads one
> at a time. Clean up with solder wick and if solder remains in the holes,
> heat the pads and push the solder out with a wooden toothpick.
> Replace the PA transistors with the K2PAKIT from Elecraft - it has matched
> PA transistors. I can give you some tests to check with the PA transistors
> out to check whether transistors Q11 and Q13 are OK (they are included with
> the K2PAKIT).
>
>
> 73,
> Don W3FPR
>
>
> On 2/19/2018 10:20 AM, David Perrin wrote:
> > Hi-
> >
> > Two questions?
> >
> > After 18 years my K2 doesn’t turn on. I did it. I must have incorrectly
> wired the Serial cable. When it got plugged in - that did it.
> >
> > There is power thru the Power button. With the radio disassembled to the
> main pc board, (sans everything that can plug into the main board) and
> power applied thru the 1/8” coaxial power connector power doesn’t seem to
> get beyond that.
> >
> > I am not in a place where I can get more parts out on the bench, nor the
> equipment except for a cheap digital Voltmeter.
> >
> > Question 1: Is there someone in the central Florida area who knows this
> radio and can shed some light on my problem?
> >
> > Question 2: Is there someone in central Florida who repairs the K2?
> >
> > Thanks for reading.
> >
> > 73 de Dave
> >
> > [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
> 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]

Don Wilhelm

Re: K2 is dead?

Ken and all,

Thank you for that endorsement - I endeavor to return a radio working
'the best it can be' no matter if it is an official Elecraft repair on
an independent repair.

At the current time, I am doing support for Elecraft as well as both
Elecraft repairs and independent repairs for the Classic (legacy) gear -
the K2, K1, KX1 and XV series tranverters. All that keeps me quite busy
and my turn-around time on repairs has slowed since I have been also
doing support activities via both email and phone directly for Elecraft.

Be that as it may, I still do many repairs of the K2, K1, KX1 and XV
series tranverters, but my turn-around time has slowed a bit because of
my other activities.

Send me a direct email (w3fpr@embarqmailcom) asking for my service and I
will send you my service form. If you prefer to go through the official
Elecraft repair channel, send an email to [hidden email] and ask
for an RSA number and form - wait until you have received the RSA number
and shipping instructions before sending your K2.

RSA repairs of the K2, K1, KX1 and XV series transverters are not done
in Watsonville, but at my address in North Carolina, or possibility by
Gary in Arizona.

73,
Don W3FPR

On 2/19/2018 8:55 PM, Ken G Kopp wrote:

> I'll add my enthusiastic endorsement for Don, W3FPR. He's prompt and
> reasonable.
>
> 73!
>
> Ken - K0PP
>
> On Feb 19, 2018 18:50, "Bill Johnson" <[hidden email]> wrote:
>
>> Dave, my suggestion: send it Don who is a fantastic expert. He is very
>> reasonalble in his fees. While I am technically competent, and have the
>> equipment, he is natural at it. I have to work at it, because unlike Don,
>> don't do it day to day. I have sent equipment to him and it is done in no
>> time. If you have time to do your own work, then give that a shot. For
>> me, life it too short.
>>
>>
>> 73,
>> Bill
>> K9YEQ
>>
>>
>>
>> -----Original Message-----
>> From: [hidden email] [mailto:elecraft-bounces@
>> mailman.qth.net] On Behalf Of Don Wilhelm
>> Sent: Monday, February 19, 2018 6:28 PM
>> To: David Perrin <[hidden email]>; Elecraft <[hidden email]>
>> Subject: Re: [Elecraft] K2 is dead?
>>
>> David,[Bill] n
>>
>> There are several possibilities.
>> While it is possible that the "serial" cable may have been the the
>> problem, that could have damaged the KIO2 (or KPA100), but it could also
>> have damaged the MCU (U6) on the control board.
>>
>> Did it go into transmit with no load? If so, it may be that Q7 and Q8
>> have been damaged. Check the resistance from the collector to ground.
>> It should start out at about 2k ohms and increase in resistance as the
>> electrolytics charge. If it is substantially less than that, the PA
>> transistors may have been damaged - that will trip the internal resettable
>> fuse (F1).
>> To remove 12v power from the PA transistors, you can remove them (do that
>> if the resistance check reveals them to be shorted), or you can remove
>> transformer T3.
>> After removing 12v from the PA transistors, see if the K2 powers on.
>>
>> I don't know of anyone who is skilled in troubleshooting the K2 in central
>> FL, but someone may volunteer.
>>
>> If you remove the PA transistors and do not have adequate desoldering
>> ability, clip the leads at the transistor bodies and remove the leads one
>> at a time. Clean up with solder wick and if solder remains in the holes,
>> heat the pads and push the solder out with a wooden toothpick.
>> Replace the PA transistors with the K2PAKIT from Elecraft - it has matched
>> PA transistors. I can give you some tests to check with the PA transistors
>> out to check whether transistors Q11 and Q13 are OK (they are included with
>> the K2PAKIT).
>>
>>
>> 73,
>> Don W3FPR
>>
>>
>> On 2/19/2018 10:20 AM, David Perrin wrote:
>>> Hi-
>>>
>>> Two questions?
>>>
>>> After 18 years my K2 doesn’t turn on. I did it. I must have incorrectly
>> wired the Serial cable. When it got plugged in - that did it.
>>>
>>> There is power thru the Power button. With the radio disassembled to the
>> main pc board, (sans everything that can plug into the main board) and
>> power applied thru the 1/8” coaxial power connector power doesn’t seem to
>> get beyond that.
>>>
>>> I am not in a place where I can get more parts out on the bench, nor the
>> equipment except for a cheap digital Voltmeter.
>>>
>>> Question 1: Is there someone in the central Florida area who knows this
>> radio and can shed some light on my problem?
>>>
>>> Question 2: Is there someone in central Florida who repairs the K2?
>>>
>>> Thanks for reading.
>>>
>>> 73 de Dave
>>>
>>> [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
>> 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
> 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]
>