Elecraft

KPA-1500 failed!

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Peter W2IRT

KPA-1500 failed!

I was operating in the ARRL-CW contest this morning and on 20m, with a 1.2:1
SWR on the Yagi, all of a sudden I saw my power drop to about 450-500W with
about 40W in. Worked a few stations but not as easily as when I turned
everything on this morning. Switched over to phone and made a few contacts.
Audio is fine barefoot with 100W out of the K3s-which suffered blown finals
itself during CQWW SSB last fall, but with the amp in I got reports that my
audio was badly distorted.

Before I send it in, is there anything I should look at or any diagnostics I
can easily perform? For the cost of this, I'd have thought protection would
have kicked in to prevent anything untoward from happening. I'm in complete
disbelief, to be honest.

---------------------------------------------
73 and Good DX
Peter, W2IRT

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Lovin' my K3S (S/N 10023)
73, Peter W2IRT

Wes Stewart-2

Re: KPA-1500 failed!

I think a two-tone test is the best evaluation tool.. The generator is built
into the K3 if you have another receiver that you can use to listen to the amp
output. I use an SDR-IQ which is a very nice tool for this but any other SDR
would do.

Sorry for your pain.

Wes N7WS

On 2/16/2019 7:28 AM, [hidden email] wrote:

> I was operating in the ARRL-CW contest this morning and on 20m, with a 1.2:1
> SWR on the Yagi, all of a sudden I saw my power drop to about 450-500W with
> about 40W in. Worked a few stations but not as easily as when I turned
> everything on this morning. Switched over to phone and made a few contacts.
> Audio is fine barefoot with 100W out of the K3s-which suffered blown finals
> itself during CQWW SSB last fall, but with the amp in I got reports that my
> audio was badly distorted.
>
> Before I send it in, is there anything I should look at or any diagnostics I
> can easily perform? For the cost of this, I'd have thought protection would
> have kicked in to prevent anything untoward from happening. I'm in complete
> disbelief, to be honest.
>
> ---------------------------------------------
> 73 and Good DX
> Peter, W2IRT
>

Dave wo2x

Re: KPA-1500 failed!

I talked to Peter on the phone. He has no bias current when amp is transmitting with no power applied (key on SSB without talking. He is reading 54 volts and has tried power cycling amp from power supply switch and reseated all cables. Definitely BAD distortion on SSB (we are close enough to hear each other). Looks like one RF device let loose and it is dragging down the bias voltage. That is my guess.

Dave wo2x

-----Original Message-----
From: [hidden email] <[hidden email]> On Behalf Of Wes
Sent: Saturday, February 16, 2019 9:49 AM
To: [hidden email]
Subject: Re: [Elecraft] KPA-1500 failed!

I think a two-tone test is the best evaluation tool.. The generator is built into the K3 if you have another receiver that you can use to listen to the amp output. I use an SDR-IQ which is a very nice tool for this but any other SDR would do.

Sorry for your pain.

Wes N7WS

On 2/16/2019 7:28 AM, [hidden email] wrote:

> I was operating in the ARRL-CW contest this morning and on 20m, with a
> 1.2:1 SWR on the Yagi, all of a sudden I saw my power drop to about
> 450-500W with about 40W in. Worked a few stations but not as easily as
> when I turned everything on this morning. Switched over to phone and made a few contacts.
> Audio is fine barefoot with 100W out of the K3s-which suffered blown
> finals itself during CQWW SSB last fall, but with the amp in I got
> reports that my audio was badly distorted.
>
> Before I send it in, is there anything I should look at or any
> diagnostics I can easily perform? For the cost of this, I'd have
> thought protection would have kicked in to prevent anything untoward
> from happening. I'm in complete disbelief, to be honest.
>
> ---------------------------------------------
> 73 and Good DX
> Peter, W2IRT
>

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Paul Baldock

Re: KPA-1500 failed!

It sounds like one of the output devices have failed. Half power out
is usually the indicator. A number here have reported this happening.
It would be nice to know why this problem is occurring and if
Elecraft are working on a fix.

- Paul

At 07:10 AM 2/16/2019, [hidden email] wrote:

>I talked to Peter on the phone. He has no bias current when amp is
>transmitting with no power applied (key on SSB without talking. He
>is reading 54 volts and has tried power cycling amp from power
>supply switch and reseated all cables. Definitely BAD distortion on
>SSB (we are close enough to hear each other). Looks like one RF
>device let loose and it is dragging down the bias voltage. That is my guess.
>
>Dave wo2x
>
>
>-----Original Message-----
>From: [hidden email]
><[hidden email]> On Behalf Of Wes
>Sent: Saturday, February 16, 2019 9:49 AM
>To: [hidden email]
>Subject: Re: [Elecraft] KPA-1500 failed!
>
>I think a two-tone test is the best evaluation tool.. The generator
>is built into the K3 if you have another receiver that you can use
>to listen to the amp output. I use an SDR-IQ which is a very nice
>tool for this but any other SDR would do.
>
>Sorry for your pain.
>
>Wes N7WS
>
>On 2/16/2019 7:28 AM, [hidden email] wrote:
> > I was operating in the ARRL-CW contest this morning and on 20m, with a
> > 1.2:1 SWR on the Yagi, all of a sudden I saw my power drop to about
> > 450-500W with about 40W in. Worked a few stations but not as easily as
> > when I turned everything on this morning. Switched over to phone
> and made a few contacts.
> > Audio is fine barefoot with 100W out of the K3s-which suffered blown
> > finals itself during CQWW SSB last fall, but with the amp in I got
> > reports that my audio was badly distorted.
> >
> > Before I send it in, is there anything I should look at or any
> > diagnostics I can easily perform? For the cost of this, I'd have
> > thought protection would have kicked in to prevent anything untoward
> > from happening. I'm in complete disbelief, to be honest.
> >
> > ---------------------------------------------
> > 73 and Good DX
> > Peter, W2IRT
> >
>
>______________________________________________________________
>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]

Peter W2IRT

Re: KPA-1500 failed!

Exact same thing happened to my K3s in October, now my KPA-1500. Yeah, So
done here. Once repaired and confirmed working it will be up for sale. Going
back to a tube amp after this.

- pjd

-----Original Message-----
From: [hidden email] <[hidden email]> On
Behalf Of Paul Baldock
Sent: Saturday, February 16, 2019 10:28 AM
To: [hidden email]; [hidden email]
Subject: Re: [Elecraft] KPA-1500 failed!

It sounds like one of the output devices have failed. Half power out is
usually the indicator. A number here have reported this happening.
It would be nice to know why this problem is occurring and if Elecraft are
working on a fix.

- Paul

At 07:10 AM 2/16/2019, [hidden email] wrote:

>I talked to Peter on the phone. He has no bias current when amp is
>transmitting with no power applied (key on SSB without talking. He is
>reading 54 volts and has tried power cycling amp from power supply
>switch and reseated all cables. Definitely BAD distortion on SSB (we
>are close enough to hear each other). Looks like one RF device let
>loose and it is dragging down the bias voltage. That is my guess.
>
>Dave wo2x
>
>
>-----Original Message-----
>From: [hidden email]
><[hidden email]> On Behalf Of Wes
>Sent: Saturday, February 16, 2019 9:49 AM
>To: [hidden email]
>Subject: Re: [Elecraft] KPA-1500 failed!
>
>I think a two-tone test is the best evaluation tool.. The generator is
>built into the K3 if you have another receiver that you can use to
>listen to the amp output. I use an SDR-IQ which is a very nice tool
>for this but any other SDR would do.
>
>Sorry for your pain.
>
>Wes N7WS
>
>On 2/16/2019 7:28 AM, [hidden email] wrote:
> > I was operating in the ARRL-CW contest this morning and on 20m, with
> > a
> > 1.2:1 SWR on the Yagi, all of a sudden I saw my power drop to about
> > 450-500W with about 40W in. Worked a few stations but not as easily
> > as when I turned everything on this morning. Switched over to phone
> and made a few contacts.
> > Audio is fine barefoot with 100W out of the K3s-which suffered blown
> > finals itself during CQWW SSB last fall, but with the amp in I got
> > reports that my audio was badly distorted.
> >
> > Before I send it in, is there anything I should look at or any
> > diagnostics I can easily perform? For the cost of this, I'd have
> > thought protection would have kicked in to prevent anything untoward
> > from happening. I'm in complete disbelief, to be honest.
> >
> > ---------------------------------------------
> > 73 and Good DX
> > Peter, W2IRT
> >
>
>______________________________________________________________
>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]

______________________________________________________________
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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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Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

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Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

Lovin' my K3S (S/N 10023)
73, Peter W2IRT

Mark Goldberg

Re: KPA-1500 failed!

It's been said there are no coincidences. Have you checked your coaxes /
connectors? I agree that protection built in should not allow radios to
blow finals, but this sounds like too much of a coincidence with two
different radios blowing to not be an external intermittent connection. Try
wiggling all the cables with low power. Unfortunately, sometimes a problem
will only show up as arcing at high power. Is there another HAM near you
with a powerful amp and antenna close to yours?

Best of luck,

Mark
W7MLG

On Sat, Feb 16, 2019 at 8:50 AM <[hidden email]> wrote:

> Exact same thing happened to my K3s in October, now my KPA-1500. Yeah, So
> done here. Once repaired and confirmed working it will be up for sale.
> Going
> back to a tube amp after this.
>
> - pjd
>
> -----Original Message-----
> From: [hidden email] <[hidden email]>
> On
> Behalf Of Paul Baldock
> Sent: Saturday, February 16, 2019 10:28 AM
> To: [hidden email]; [hidden email]
> Subject: Re: [Elecraft] KPA-1500 failed!
>
> It sounds like one of the output devices have failed. Half power out is
> usually the indicator. A number here have reported this happening.
> It would be nice to know why this problem is occurring and if Elecraft are
> working on a fix.
>
> - Paul
>
> At 07:10 AM 2/16/2019, [hidden email] wrote:
> >I talked to Peter on the phone. He has no bias current when amp is
> >transmitting with no power applied (key on SSB without talking. He is
> >reading 54 volts and has tried power cycling amp from power supply
> >switch and reseated all cables. Definitely BAD distortion on SSB (we
> >are close enough to hear each other). Looks like one RF device let
> >loose and it is dragging down the bias voltage. That is my guess.
> >
> >Dave wo2x
> >
> >
> >-----Original Message-----
> >From: [hidden email]
> ><[hidden email]> On Behalf Of Wes
> >Sent: Saturday, February 16, 2019 9:49 AM
> >To: [hidden email]
> >Subject: Re: [Elecraft] KPA-1500 failed!
> >
> >I think a two-tone test is the best evaluation tool.. The generator is
> >built into the K3 if you have another receiver that you can use to
> >listen to the amp output. I use an SDR-IQ which is a very nice tool
> >for this but any other SDR would do.
> >
> >Sorry for your pain.
> >
> >Wes N7WS
> >
> >On 2/16/2019 7:28 AM, [hidden email] wrote:
> > > I was operating in the ARRL-CW contest this morning and on 20m, with
> > > a
> > > 1.2:1 SWR on the Yagi, all of a sudden I saw my power drop to about
> > > 450-500W with about 40W in. Worked a few stations but not as easily
> > > as when I turned everything on this morning. Switched over to phone
> > and made a few contacts.
> > > Audio is fine barefoot with 100W out of the K3s-which suffered blown
> > > finals itself during CQWW SSB last fall, but with the amp in I got
> > > reports that my audio was badly distorted.
> > >
> > > Before I send it in, is there anything I should look at or any
> > > diagnostics I can easily perform? For the cost of this, I'd have
> > > thought protection would have kicked in to prevent anything untoward
> > > from happening. I'm in complete disbelief, to be honest.
> > >
> > > ---------------------------------------------
> > > 73 and Good DX
> > > Peter, W2IRT
> > >
> >
> >______________________________________________________________
> >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]
>

Dave wo2x

Re: KPA-1500 failed!

His radio blew one final while driving the KPA1500 in the fall.

Now his amp blew one LDMOS.

I’ve been to Peter’s house and used a TDR to check all of his antennas, cabling, and switching. Cable connectors replaced last year.

I agree it is good idea to check everything again. Looking at the amp fault log today did not show signs of anything arcing

Dave wo2x

Sent from my waxed string and tin cans.

> On Feb 16, 2019, at 11:01 AM, Mark Goldberg <[hidden email]> wrote:
>
> It's been said there are no coincidences. Have you checked your coaxes / connectors? I agree that protection built in should not allow radios to blow finals, but this sounds like too much of a coincidence with two different radios blowing to not be an external intermittent connection. Try wiggling all the cables with low power. Unfortunately, sometimes a problem will only show up as arcing at high power. Is there another HAM near you with a powerful amp and antenna close to yours?
>
> Best of luck,
>
> Mark
> W7MLG
>
>
>> On Sat, Feb 16, 2019 at 8:50 AM <[hidden email]> wrote:
>> Exact same thing happened to my K3s in October, now my KPA-1500. Yeah, So
>> done here. Once repaired and confirmed working it will be up for sale. Going
>> back to a tube amp after this.
>>
>> - pjd
>>
>> -----Original Message-----
>> From: [hidden email] <[hidden email]> On
>> Behalf Of Paul Baldock
>> Sent: Saturday, February 16, 2019 10:28 AM
>> To: [hidden email]; [hidden email]
>> Subject: Re: [Elecraft] KPA-1500 failed!
>>
>> It sounds like one of the output devices have failed. Half power out is
>> usually the indicator. A number here have reported this happening.
>> It would be nice to know why this problem is occurring and if Elecraft are
>> working on a fix.
>>
>> - Paul
>>
>> At 07:10 AM 2/16/2019, [hidden email] wrote:
>> >I talked to Peter on the phone. He has no bias current when amp is
>> >transmitting with no power applied (key on SSB without talking. He is
>> >reading 54 volts and has tried power cycling amp from power supply
>> >switch and reseated all cables. Definitely BAD distortion on SSB (we
>> >are close enough to hear each other). Looks like one RF device let
>> >loose and it is dragging down the bias voltage. That is my guess.
>> >
>> >Dave wo2x
>> >
>> >
>> >-----Original Message-----
>> >From: [hidden email]
>> ><[hidden email]> On Behalf Of Wes
>> >Sent: Saturday, February 16, 2019 9:49 AM
>> >To: [hidden email]
>> >Subject: Re: [Elecraft] KPA-1500 failed!
>> >
>> >I think a two-tone test is the best evaluation tool.. The generator is
>> >built into the K3 if you have another receiver that you can use to
>> >listen to the amp output. I use an SDR-IQ which is a very nice tool
>> >for this but any other SDR would do.
>> >
>> >Sorry for your pain.
>> >
>> >Wes N7WS
>> >
>> >On 2/16/2019 7:28 AM, [hidden email] wrote:
>> > > I was operating in the ARRL-CW contest this morning and on 20m, with
>> > > a
>> > > 1.2:1 SWR on the Yagi, all of a sudden I saw my power drop to about
>> > > 450-500W with about 40W in. Worked a few stations but not as easily
>> > > as when I turned everything on this morning. Switched over to phone
>> > and made a few contacts.
>> > > Audio is fine barefoot with 100W out of the K3s-which suffered blown
>> > > finals itself during CQWW SSB last fall, but with the amp in I got
>> > > reports that my audio was badly distorted.
>> > >
>> > > Before I send it in, is there anything I should look at or any
>> > > diagnostics I can easily perform? For the cost of this, I'd have
>> > > thought protection would have kicked in to prevent anything untoward
>> > > from happening. I'm in complete disbelief, to be honest.
>> > >
>> > > ---------------------------------------------
>> > > 73 and Good DX
>> > > Peter, W2IRT
>> > >
>> >
>> >______________________________________________________________
>> >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]

Wes Stewart-2

Re: KPA-1500 failed!

In reply to this post by Mark Goldberg

Unfortunately, you're wrong. My K3S has failed multiple times. Fortunately, my
KPA500 has not. I'm not in the market for a KPA1500.

Wes N7WS

On 2/16/2019 9:01 AM, Mark Goldberg wrote:

> It's been said there are no coincidences. Have you checked your coaxes /
> connectors? I agree that protection built in should not allow radios to
> blow finals, but this sounds like too much of a coincidence with two
> different radios blowing to not be an external intermittent connection. Try
> wiggling all the cables with low power. Unfortunately, sometimes a problem
> will only show up as arcing at high power. Is there another HAM near you
> with a powerful amp and antenna close to yours?
>
> Best of luck,
>
> Mark
> W7MLG
>
>
> On Sat, Feb 16, 2019 at 8:50 AM <[hidden email]> wrote:
>
>> Exact same thing happened to my K3s in October, now my KPA-1500. Yeah, So
>> done here. Once repaired and confirmed working it will be up for sale.
>> Going
>> back to a tube amp after this.
>>
>> - pjd
>>
>> -----Original Message-----
>> From: [hidden email] <[hidden email]>
>> On
>> Behalf Of Paul Baldock
>> Sent: Saturday, February 16, 2019 10:28 AM
>> To: [hidden email]; [hidden email]
>> Subject: Re: [Elecraft] KPA-1500 failed!
>>
>> It sounds like one of the output devices have failed. Half power out is
>> usually the indicator. A number here have reported this happening.
>> It would be nice to know why this problem is occurring and if Elecraft are
>> working on a fix.
>>
>> - Paul
>>
>> At 07:10 AM 2/16/2019, [hidden email] wrote:
>>> I talked to Peter on the phone. He has no bias current when amp is
>>> transmitting with no power applied (key on SSB without talking. He is
>>> reading 54 volts and has tried power cycling amp from power supply
>>> switch and reseated all cables. Definitely BAD distortion on SSB (we
>>> are close enough to hear each other). Looks like one RF device let
>>> loose and it is dragging down the bias voltage. That is my guess.
>>>
>>> Dave wo2x
>>>
>>>
>>> -----Original Message-----
>>> From: [hidden email]
>>> <[hidden email]> On Behalf Of Wes
>>> Sent: Saturday, February 16, 2019 9:49 AM
>>> To: [hidden email]
>>> Subject: Re: [Elecraft] KPA-1500 failed!
>>>
>>> I think a two-tone test is the best evaluation tool.. The generator is
>>> built into the K3 if you have another receiver that you can use to
>>> listen to the amp output. I use an SDR-IQ which is a very nice tool
>>> for this but any other SDR would do.
>>>
>>> Sorry for your pain.
>>>
>>> Wes N7WS
>>>
>>> On 2/16/2019 7:28 AM, [hidden email] wrote:
>>>> I was operating in the ARRL-CW contest this morning and on 20m, with
>>>> a
>>>> 1.2:1 SWR on the Yagi, all of a sudden I saw my power drop to about
>>>> 450-500W with about 40W in. Worked a few stations but not as easily
>>>> as when I turned everything on this morning. Switched over to phone
>>> and made a few contacts.
>>>> Audio is fine barefoot with 100W out of the K3s-which suffered blown
>>>> finals itself during CQWW SSB last fall, but with the amp in I got
>>>> reports that my audio was badly distorted.
>>>>
>>>> Before I send it in, is there anything I should look at or any
>>>> diagnostics I can easily perform? For the cost of this, I'd have
>>>> thought protection would have kicked in to prevent anything untoward
>>>> from happening. I'm in complete disbelief, to be honest.
>>>>
>>>> ---------------------------------------------
>>>> 73 and Good DX
>>>> Peter, W2IRT
>>>>

Bob McGraw - K4TAX

Re: KPA-1500 failed!

In reply to this post by Dave wo2x

Do not trust PL-259 connectors installed only "finger tight". Today many
of those PL-259 connectors "look good" but are really poor quality
connectors.    ALWAYS snug the PL-259's with a pair of 4" channel lock
pliers.   You'd be amazed how many strange issues will go away.

Not saying this is or was the cause of failure, but I've seen it and
experienced it too many times.

Also, for other reasons, I run the ALC from my KPA500 to my K3S.
Again, another issue of concern resolved.

73

Bob, K4TAX

On 2/16/2019 10:13 AM, Dave wrote:

> His radio blew one final while driving the KPA1500 in the fall.
>
> Now his amp blew one LDMOS.
>
> I’ve been to Peter’s house and used a TDR to check all of his antennas, cabling, and switching. Cable connectors replaced last year.
>
> I agree it is good idea to check everything again. Looking at the amp fault log today did not show signs of anything arcing
>
> Dave wo2x
>
> Sent from my waxed string and tin cans.
>
>> On Feb 16, 2019, at 11:01 AM, Mark Goldberg <[hidden email]> wrote:
>>
>> It's been said there are no coincidences. Have you checked your coaxes / connectors? I agree that protection built in should not allow radios to blow finals, but this sounds like too much of a coincidence with two different radios blowing to not be an external intermittent connection. Try wiggling all the cables with low power. Unfortunately, sometimes a problem will only show up as arcing at high power. Is there another HAM near you with a powerful amp and antenna close to yours?
>>
>> Best of luck,
>>
>> Mark
>> W7MLG
>>
>>
>>> On Sat, Feb 16, 2019 at 8:50 AM <[hidden email]> wrote:
>>> Exact same thing happened to my K3s in October, now my KPA-1500. Yeah, So
>>> done here. Once repaired and confirmed working it will be up for sale. Going
>>> back to a tube amp after this.
>>>
>>> - pjd
>>>
>>> -----Original Message-----
>>> From: [hidden email] <[hidden email]> On
>>> Behalf Of Paul Baldock
>>> Sent: Saturday, February 16, 2019 10:28 AM
>>> To: [hidden email]; [hidden email]
>>> Subject: Re: [Elecraft] KPA-1500 failed!
>>>
>>> It sounds like one of the output devices have failed. Half power out is
>>> usually the indicator. A number here have reported this happening.
>>> It would be nice to know why this problem is occurring and if Elecraft are
>>> working on a fix.
>>>
>>> - Paul
>>>
>>> At 07:10 AM 2/16/2019, [hidden email] wrote:
>>>> I talked to Peter on the phone. He has no bias current when amp is
>>>> transmitting with no power applied (key on SSB without talking. He is
>>>> reading 54 volts and has tried power cycling amp from power supply
>>>> switch and reseated all cables. Definitely BAD distortion on SSB (we
>>>> are close enough to hear each other). Looks like one RF device let
>>>> loose and it is dragging down the bias voltage. That is my guess.
>>>>
>>>> Dave wo2x
>>>>
>>>>
>>>> -----Original Message-----
>>>> From: [hidden email]
>>>> <[hidden email]> On Behalf Of Wes
>>>> Sent: Saturday, February 16, 2019 9:49 AM
>>>> To: [hidden email]
>>>> Subject: Re: [Elecraft] KPA-1500 failed!
>>>>
>>>> I think a two-tone test is the best evaluation tool.. The generator is
>>>> built into the K3 if you have another receiver that you can use to
>>>> listen to the amp output. I use an SDR-IQ which is a very nice tool
>>>> for this but any other SDR would do.
>>>>
>>>> Sorry for your pain.
>>>>
>>>> Wes N7WS
>>>>
>>>> On 2/16/2019 7:28 AM, [hidden email] wrote:
>>>>> I was operating in the ARRL-CW contest this morning and on 20m, with
>>>>> a
>>>>> 1.2:1 SWR on the Yagi, all of a sudden I saw my power drop to about
>>>>> 450-500W with about 40W in. Worked a few stations but not as easily
>>>>> as when I turned everything on this morning. Switched over to phone
>>>> and made a few contacts.
>>>>> Audio is fine barefoot with 100W out of the K3s-which suffered blown
>>>>> finals itself during CQWW SSB last fall, but with the amp in I got
>>>>> reports that my audio was badly distorted.
>>>>>
>>>>> Before I send it in, is there anything I should look at or any
>>>>> diagnostics I can easily perform? For the cost of this, I'd have
>>>>> thought protection would have kicked in to prevent anything untoward
>>>>> from happening. I'm in complete disbelief, to be honest.
>>>>>
>>>>> ---------------------------------------------
>>>>> 73 and Good DX
>>>>> Peter, W2IRT
>>>>>
>>>> ______________________________________________________________
>>>> 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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>>>> 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]
>>>
>>> ______________________________________________________________
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>>> Help: http://mailman.qth.net/mmfaq.htm
>>> Post: mailto:[hidden email]
>>>
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> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
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>
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Eric Swartz - WA6HHQ

Re: KPA-1500 failed!

Administrator

In reply to this post by Peter W2IRT

Hi Peter,

I'm sorry to hear about this failure and deeply apologize for the problem.

I'll follow up with another email to you to diagnose what actually happened.

In any case we'll deal with it quickly and get your amp repaired asap.

Eric
elecraft.com
_..._

> On Feb 16, 2019, at 6:28 AM, <[hidden email]> <[hidden email]> wrote:
>
> I was operating in the ARRL-CW contest this morning and on 20m, with a 1.2:1
> SWR on the Yagi, all of a sudden I saw my power drop to about 450-500W with
> about 40W in. Worked a few stations but not as easily as when I turned
> everything on this morning. Switched over to phone and made a few contacts.
> Audio is fine barefoot with 100W out of the K3s-which suffered blown finals
> itself during CQWW SSB last fall, but with the amp in I got reports that my
> audio was badly distorted.
>
> Before I send it in, is there anything I should look at or any diagnostics I
> can easily perform? For the cost of this, I'd have thought protection would
> have kicked in to prevent anything untoward from happening. I'm in complete
> disbelief, to be honest.
>
> ---------------------------------------------
> 73 and Good DX
> Peter, W2IRT
>
>
>
> ______________________________________________________________
> 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]

Bob McGraw - K4TAX

Re: KPA3A Failure & related

In reply to this post by Wes Stewart-2

This discussion has risen its nasty head earlier. Wes and I exchanged
several private e-mails on the topic. Here is what I've learned:

My purchased new from the factory my K3S -100 in August of 2015. With it
I drove my AL-80B with 60 to 80 watts for some two years.   Absolute no
issues of concern.    In April of 2018 I purchased a new KPA500 and put
it in place of the AL-80B.   I drove the KPA500 with my K3S at 15 watts
for some 2 weeks. Then reports of "fuzzy audio" surfaced. The 2 tone
test revealed excessive IMD. I contacted Tech Support and they arranged
to send me a LPA3 and a KPA3A.   These were installed and all was well
for about one week. Then again the reports of "fuzzy audio". I
contacted Tech Support again and they said "send it in".   The service
report indicated they replaced the KPA3A with a rev E which is reported
to be more stable. An interesting comment on the Elecraft Service
report; "Due to failure of the stable rev E amp, this indicates
something in the shack.   Possible kickback from and amplifier.   It is
likely to happen again if the root cause is not found. ........"
UGH...folks, the amp is a KPA500!     >> HOUSTON - DO WE HAVE A PROBLEM?>>

In the discussions via e-mail and here on the reflector which followed,
I learned of others which experienced the same type issues. I asked
"what's the solution".   Interestingly the answer came back [I don't
recall from whom} "stay away from 15 watts". Since then I have driven
my KPA500 with 20 watts .....PLUS I have connected and engaged the ALC
from the KPA500 to my K3S. This is a menu item in the K3S. Now some
may not like the ALC connection and activation.

My thinking is that IF there are any spikes originated with the rise of
the CW signal or voice signal this may overdrive the amp.   With my P3 I
see this A LOT on SSB signals on the bands which exhibit initial ALC
overshoot. This is both on CW and SSB.    Makes me wonder what does the
input impedance of the KPA500 does when hit with a millisecond or so of
excessive drive? Not long enough to activate the attenuator or throw a
fault signal. I do know that tube amps reflect to their input the
effective tuning of the output. Could this be an issue with solid
state amps where the input impedance goes to zero thus placing in effect
short on the driving transceiver? Mind you not long enough to throw a
fault signal but........what does it do to the driving stage? I've
not measured it and am not exactly sure how to accomplish this. It may
not be the issue at all.   Perhaps some of you more technical gurus can
expound further on the topic.

I do know factually since the change to the KPA3A rev E, and I
activated the ALC between the KPA500 and my K3S the issue has not reared
its ugly head. Lets hope it doesn't.

All in all, I am VERY pleased with Elecraft Tech support and extremely
pleased with my K3S, P3, KPA500 and KAT500. A winning combination.
But I'm still walking on eggs and hoping none break.

73

Bob, K4TAX

On 2/16/2019 10:24 AM, Wes wrote:

> Unfortunately, you're wrong. My K3S has failed multiple times.
> Fortunately, my KPA500 has not. I'm not in the market for a KPA1500.
>
> Wes N7WS
>
>

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Peter W2IRT

Re: KPA-1500 failed!

In reply to this post by Bob McGraw - K4TAX

I agree with you re PL-259s. I follow best practices in this regard. Quarter-turn with channel-locks after finger tight, Amphenol 83-1SP, assembled correctly, with cables swept by a TDR.

- pjd

-----Original Message-----
From: [hidden email] <[hidden email]> On Behalf Of Bob McGraw K4TAX
Sent: Saturday, February 16, 2019 12:39 PM
To: [hidden email]; wrayplace <[hidden email]>
Subject: Re: [Elecraft] KPA-1500 failed!

Do not trust PL-259 connectors installed only "finger tight". Today many of those PL-259 connectors "look good" but are really poor quality connectors. ALWAYS snug the PL-259's with a pair of 4" channel lock pliers. You'd be amazed how many strange issues will go away.

Not saying this is or was the cause of failure, but I've seen it and experienced it too many times.

Also, for other reasons, I run the ALC from my KPA500 to my K3S. Again, another issue of concern resolved.

73

Bob, K4TAX

On 2/16/2019 10:13 AM, Dave wrote:

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Lovin' my K3S (S/N 10023)
73, Peter W2IRT

Jim Brown-10

Re: KPA-1500 failed!

In reply to this post by Bob McGraw - K4TAX

On 2/16/2019 9:39 AM, Bob McGraw K4TAX wrote:
> Do not trust PL-259 connectors installed only "finger tight". Today
> many of those PL-259 connectors "look good" but are really poor
> quality connectors.

If you live in North America, the ONLY good PL-259 connector is one that
labeled Amphenol 83-1SP. Most others are JUNK. I'm told there are some
other decent brands sold in EU.

> ALWAYS snug the PL-259's with a pair of 4" channel lock pliers.

RIGHT. And always be VERY careful about how you solder them, especially
the shield.

73, Jim K9YC

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stengrevics

Re: KPA-1500 failed!

Who uses PL-259s? They suck. I ordered my K3S with Ns and really should have specified DINs. But, that is a retrofit project for another day.

John
WA1EAZ

> On Feb 16, 2019, at 2:47 PM, Jim Brown <[hidden email]> wrote:
>
> On 2/16/2019 9:39 AM, Bob McGraw K4TAX wrote:
>> Do not trust PL-259 connectors installed only "finger tight". Today many of those PL-259 connectors "look good" but are really poor quality connectors.
>
> If you live in North America, the ONLY good PL-259 connector is one that labeled Amphenol 83-1SP. Most others are JUNK. I'm told there are some other decent brands sold in EU.
>
>> ALWAYS snug the PL-259's with a pair of 4" channel lock pliers.
>
> RIGHT. And always be VERY careful about how you solder them, especially the shield.
>
> 73, Jim K9YC
>
> ______________________________________________________________
> 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]

Wes Stewart-2

Re: KPA-1500 failed!

Thousands of people; without issue.

Wes N7WS

On 2/16/2019 1:55 PM, John Stengrevics wrote:
> Who uses PL-259s?

______________________________________________________________
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Don Wilhelm

Re: KPA3A Failure & related

In reply to this post by Bob McGraw - K4TAX

Bob and all,

I think this problem is not so much with the amplifier, but the K3/K3S.
Consider that the switchover from the low power amplifier to the KPA3 is
in the 12 to 15 watt range. That is where the LPA is generating about
all the power it can produce. Above that range, the KPA3 kicks in and
everything is "loafing along".

Oh yes, aside from that, some amplifiers do fail for various reasons -
and I think we are mixing failures of the K3/K3S with amplifier failures
in this thread.

73,
Don W3FPR

On 2/16/2019 1:43 PM, Bob McGraw K4TAX wrote:

> This discussion has risen its nasty head earlier. Wes and I exchanged
> several private e-mails on the topic. Here is what I've learned:
>
> My purchased new from the factory my K3S -100 in August of 2015. With it
> I drove my AL-80B with 60 to 80 watts for some two years.   Absolute no
> issues of concern.    In April of 2018 I purchased a new KPA500 and put
> it in place of the AL-80B.   I drove the KPA500 with my K3S at 15 watts
> for some 2 weeks. Then reports of "fuzzy audio" surfaced. The 2 tone
> test revealed excessive IMD. I contacted Tech Support and they arranged
> to send me a LPA3 and a KPA3A.   These were installed and all was well
> for about one week. Then again the reports of "fuzzy audio". I
> contacted Tech Support again and they said "send it in".   The service
> report indicated they replaced the KPA3A with a rev E which is reported
> to be more stable. An interesting comment on the Elecraft Service
> report; "Due to failure of the stable rev E amp, this indicates
> something in the shack.   Possible kickback from and amplifier.   It is
> likely to happen again if the root cause is not found. ........"
> UGH...folks, the amp is a KPA500!     >> HOUSTON - DO WE HAVE A PROBLEM?>>
>
> In the discussions via e-mail and here on the reflector which followed,
> I learned of others which experienced the same type issues. I asked
> "what's the solution".   Interestingly the answer came back [I don't
> recall from whom} "stay away from 15 watts". Since then I have driven
> my KPA500 with 20 watts .....PLUS I have connected and engaged the ALC
> from the KPA500 to my K3S. This is a menu item in the K3S. Now some
> may not like the ALC connection and activation.
>
> My thinking is that IF there are any spikes originated with the rise of
> the CW signal or voice signal this may overdrive the amp.   With my P3 I
> see this A LOT on SSB signals on the bands which exhibit initial ALC
> overshoot. This is both on CW and SSB.    Makes me wonder what does the
> input impedance of the KPA500 does when hit with a millisecond or so of
> excessive drive? Not long enough to activate the attenuator or throw a
> fault signal. I do know that tube amps reflect to their input the
> effective tuning of the output. Could this be an issue with solid
> state amps where the input impedance goes to zero thus placing in effect
> short on the driving transceiver? Mind you not long enough to throw a
> fault signal but........what does it do to the driving stage? I've
> not measured it and am not exactly sure how to accomplish this. It may
> not be the issue at all.   Perhaps some of you more technical gurus can
> expound further on the topic.
>
> I do know factually since the change to the KPA3A rev E, and I
> activated the ALC between the KPA500 and my K3S the issue has not reared
> its ugly head. Lets hope it doesn't.
>
> All in all, I am VERY pleased with Elecraft Tech support and extremely
> pleased with my K3S, P3, KPA500 and KAT500. A winning combination. But
> I'm still walking on eggs and hoping none break.
>
> 73
>
> Bob, K4TAX

Jorge Diez - CX6VM-2

Re: KPA-1500 failed!

In reply to this post by Wes Stewart-2

Guys

the problem here is not who use PL259 or what coaxial is using. I think
Peter and most of us, and mostly if you do contests, is not that, we are
using good coax and connectors over the years and no problem with other
radios or amplifiers, thats what Peter said.

If you are in a contest, you prepear your station to not fail. Robust
radios and amplifiers, not only pretty ones

Hopefully guys in USA will have this problem solved *easily*

But what about if you dont live in USA? I didnt buy Expert 1.3K amplifier
because many owners told me about it´s fail. Is very expensive and dificult
to deal with customs to take it to USA and back to Uruguay to repair it.

So, KPA1500 is a robust amplifier? Of course always will be a problem, but
is 1% or 25% of the cases?

And I dont want parts sent by Elecraft to fix it, I want an amp that not
fail

73,
Jorge
CX6VM/CW5W

El sáb., 16 feb. 2019 a las 18:20, Wes (<[hidden email]>) escribió:

> Thousands of people; without issue.
>
> Wes N7WS
>
> On 2/16/2019 1:55 PM, John Stengrevics wrote:
> > Who uses PL-259s?
>
> ______________________________________________________________
> 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]

--
73,
Jorge
CX6VM/CW5W
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Drew AF2Z

Re: KPA-1500 failed!

In reply to this post by Peter W2IRT

FWIW, I use NO-OX-ID contact grease on my PL259 connectors. This allows
very tight snugging by hand, no need of wrenching.

During lightning season I frequently connect/disconnect my rig and tuner
cables. The fine film of lube on the connector threads makes a big
difference. Without it? A real PITA, not to mention wear and tear on the
the SO-239's.

73,
Drew
AF2Z

On 02/16/19 14:08, Peter Dougherty wrote:

> I agree with you re PL-259s. I follow best practices in this regard. Quarter-turn with channel-locks after finger tight, Amphenol 83-1SP, assembled correctly, with cables swept by a TDR.
>
> - pjd
>
> -----Original Message-----
> From: [hidden email] <[hidden email]> On Behalf Of Bob McGraw K4TAX
> Sent: Saturday, February 16, 2019 12:39 PM
> To: [hidden email]; wrayplace <[hidden email]>
> Subject: Re: [Elecraft] KPA-1500 failed!
>
> Do not trust PL-259 connectors installed only "finger tight". Today many of those PL-259 connectors "look good" but are really poor quality connectors. ALWAYS snug the PL-259's with a pair of 4" channel lock pliers. You'd be amazed how many strange issues will go away.
>
> Not saying this is or was the cause of failure, but I've seen it and experienced it too many times.
>
> Also, for other reasons, I run the ALC from my KPA500 to my K3S. Again, another issue of concern resolved.
>
> 73
>
> Bob, K4TAX
>
>
> On 2/16/2019 10:13 AM, Dave wrote:
>> His radio blew one final while driving the KPA1500 in the fall.
>>
>> Now his amp blew one LDMOS.
>>
>> I’ve been to Peter’s house and used a TDR to check all of his antennas, cabling, and switching. Cable connectors replaced last year.
>>
>> I agree it is good idea to check everything again. Looking at the amp fault log today did not show signs of anything arcing
>>
>> Dave wo2x
>>
>> Sent from my waxed string and tin cans.
>>
>>> On Feb 16, 2019, at 11:01 AM, Mark Goldberg <[hidden email]> wrote:
>>>
>>> It's been said there are no coincidences. Have you checked your coaxes / connectors? I agree that protection built in should not allow radios to blow finals, but this sounds like too much of a coincidence with two different radios blowing to not be an external intermittent connection. Try wiggling all the cables with low power. Unfortunately, sometimes a problem will only show up as arcing at high power. Is there another HAM near you with a powerful amp and antenna close to yours?
>>>
>>> Best of luck,
>>>
>>> Mark
>>> W7MLG
>>>
>>>
>>>> On Sat, Feb 16, 2019 at 8:50 AM <[hidden email]> wrote:
>>>> Exact same thing happened to my K3s in October, now my KPA-1500. Yeah, So
>>>> done here. Once repaired and confirmed working it will be up for sale. Going
>>>> back to a tube amp after this.
>>>>
>>>> - pjd
>>>>
>>>> -----Original Message-----
>>>> From: [hidden email] <[hidden email]> On
>>>> Behalf Of Paul Baldock
>>>> Sent: Saturday, February 16, 2019 10:28 AM
>>>> To: [hidden email]; [hidden email]
>>>> Subject: Re: [Elecraft] KPA-1500 failed!
>>>>
>>>> It sounds like one of the output devices have failed. Half power out is
>>>> usually the indicator. A number here have reported this happening.
>>>> It would be nice to know why this problem is occurring and if Elecraft are
>>>> working on a fix.
>>>>
>>>> - Paul
>>>>
>>>> At 07:10 AM 2/16/2019, [hidden email] wrote:
>>>>> I talked to Peter on the phone. He has no bias current when amp is
>>>>> transmitting with no power applied (key on SSB without talking. He is
>>>>> reading 54 volts and has tried power cycling amp from power supply
>>>>> switch and reseated all cables. Definitely BAD distortion on SSB (we
>>>>> are close enough to hear each other). Looks like one RF device let
>>>>> loose and it is dragging down the bias voltage. That is my guess.
>>>>>
>>>>> Dave wo2x
>>>>>
>>>>>
>>>>> -----Original Message-----
>>>>> From: [hidden email]
>>>>> <[hidden email]> On Behalf Of Wes
>>>>> Sent: Saturday, February 16, 2019 9:49 AM
>>>>> To: [hidden email]
>>>>> Subject: Re: [Elecraft] KPA-1500 failed!
>>>>>
>>>>> I think a two-tone test is the best evaluation tool.. The generator is
>>>>> built into the K3 if you have another receiver that you can use to
>>>>> listen to the amp output. I use an SDR-IQ which is a very nice tool
>>>>> for this but any other SDR would do.
>>>>>
>>>>> Sorry for your pain.
>>>>>
>>>>> Wes N7WS
>>>>>
>>>>> On 2/16/2019 7:28 AM, [hidden email] wrote:
>>>>>> I was operating in the ARRL-CW contest this morning and on 20m, with
>>>>>> a
>>>>>> 1.2:1 SWR on the Yagi, all of a sudden I saw my power drop to about
>>>>>> 450-500W with about 40W in. Worked a few stations but not as easily
>>>>>> as when I turned everything on this morning. Switched over to phone
>>>>> and made a few contacts.
>>>>>> Audio is fine barefoot with 100W out of the K3s-which suffered blown
>>>>>> finals itself during CQWW SSB last fall, but with the amp in I got
>>>>>> reports that my audio was badly distorted.
>>>>>>
>>>>>> Before I send it in, is there anything I should look at or any
>>>>>> diagnostics I can easily perform? For the cost of this, I'd have
>>>>>> thought protection would have kicked in to prevent anything untoward
>>>>>> from happening. I'm in complete disbelief, to be honest.
>>>>>>
>>>>>> ---------------------------------------------
>>>>>> 73 and Good DX
>>>>>> Peter, W2IRT
>>>>>>
>>>>> ______________________________________________________________
>>>>> Elecraft mailing list
>>>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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ke9uw

Re: KPA-1500 failed!

I never wrench. I just wiggle the connector as I tighten it and it tightens down into the v grooves tightly. Almost have to use a pliers to unscrew it.

Chuck Hawley
[hidden email]

Amateur Radio, KE9UW
aka Jack, BMW Motorcycles

________________________________
From: [hidden email] <[hidden email]> on behalf of Drew AF2Z <[hidden email]>
Sent: Saturday, February 16, 2019 5:07 PM
To: [hidden email]
Subject: Re: [Elecraft] KPA-1500 failed!

FWIW, I use NO-OX-ID contact grease on my PL259 connectors. This allows
very tight snugging by hand, no need of wrenching.

During lightning season I frequently connect/disconnect my rig and tuner
cables. The fine film of lube on the connector threads makes a big
difference. Without it? A real PITA, not to mention wear and tear on the
the SO-239's.

73,
Drew
AF2Z

On 02/16/19 14:08, Peter Dougherty wrote:

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Chuck, KE9UW

john@kk9a.com

Re: KPA-1500 failed!

In reply to this post by Peter W2IRT

Amphenol 83-1SP connectors are great however I have a number of Andrew
44ASP, L44P and L45P connectors in my system and I also consider to be very
high quality UHF connectors.

John KK9A

Jim Brown jim at audiosystemsgroup.com

If you live in North America, the ONLY good PL-259 connector is one that
labeled Amphenol 83-1SP. Most others are JUNK. I'm told there are some
other decent brands sold in EU.

73, Jim K9YC

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