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KPA500 max heat sink temp?

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Eric Norris-2

KPA500 max heat sink temp?

I just read in the current KPA500 Manual that max heat sink temp is 90C.
Is this true for my first-year production KPA500? I seem to remember
somethink like 75C. I cant find my old manual.

73 Eric WD6DBM
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Re: KPA500 max heat sink temp?

Hi Eric, My manual (revision B, 2011) that came with my SN 0149 says 90C maximum, page14 in the specifications. It also says drive power 30-40 watts for 500 out and I have never beed even close to that, usually 22-26 watts drive.

FYI,
Bill-AK5X

> On Jul 8, 2020, at 6:00 AM, Eric Norris <[hidden email]> wrote:
>
> I just read in the current KPA500 Manual that max heat sink temp is 90C.
> Is this true for my first-year production KPA500? I seem to remember
> somethink like 75C. I cant find my old manual.
>
> 73 Eric WD6DBM
> ______________________________________________________________
> Elecraft mailing list
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Re: KPA500 max heat sink temp?

I can confirm that KPA500 V1.00 firmware, which was the first released, had a max temperature of 90 degrees C. This has not been changed in any subsequent code.

As for the input power, the amplifier has improved over time. My original prototype KPA500 requires power in the range described (about 35 - 40 watts), while my new one (just over a year old) needs about 20 or so watts. Both are great amps!

73!
Jack, W6FB

> On Jul 8, 2020, at 1:00 PM, William Hammond via Elecraft <[hidden email]> wrote:
>
> Hi Eric, My manual (revision B, 2011) that came with my SN 0149 says 90C maximum, page14 in the specifications. It also says drive power 30-40 watts for 500 out and I have never beed even close to that, usually 22-26 watts drive.
>
> FYI,
> Bill-AK5X
>
>> On Jul 8, 2020, at 6:00 AM, Eric Norris <[hidden email]> wrote:
>>
>> I just read in the current KPA500 Manual that max heat sink temp is 90C.
>> Is this true for my first-year production KPA500? I seem to remember
>> somethink like 75C. I cant find my old manual.
>>
>> 73 Eric WD6DBM
>> ______________________________________________________________
>> 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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Eric Norris-2

Re: KPA500 max heat sink temp?

Thanks, Jack! Now the only question is, is the KPA500 a great amp, or the
greatest amp ever? I'm in the second camp.

73.5 Eric WD6DBM

On Wed, Jul 8, 2020, 1:16 PM Jack Brindle <[hidden email]> wrote:

> I can confirm that KPA500 V1.00 firmware, which was the first released,
> had a max temperature of 90 degrees C. This has not been changed in any
> subsequent code.
>
> As for the input power, the amplifier has improved over time. My original
> prototype KPA500 requires power in the range described (about 35 - 40
> watts), while my new one (just over a year old) needs about 20 or so watts.
> Both are great amps!
>
> 73!
> Jack, W6FB
>
>
> > On Jul 8, 2020, at 1:00 PM, William Hammond via Elecraft <
> [hidden email]> wrote:
> >
> > Hi Eric, My manual (revision B, 2011) that came with my SN 0149 says 90C
> maximum, page14 in the specifications. It also says drive power 30-40
> watts for 500 out and I have never beed even close to that, usually 22-26
> watts drive.
> >
> > FYI,
> > Bill-AK5X
> >
> >> On Jul 8, 2020, at 6:00 AM, Eric Norris <[hidden email]>
> wrote:
> >>
> >> I just read in the current KPA500 Manual that max heat sink temp is 90C.
> >> Is this true for my first-year production KPA500? I seem to remember
> >> somethink like 75C. I cant find my old manual.
> >>
> >> 73 Eric WD6DBM
> >> ______________________________________________________________
> >> 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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>
>

Rick Bates, NK7I

Re: KPA500 max heat sink temp?

Then you haven't used a KPA1500.

Rick NK7I

On 7/8/2020 2:11 PM, Eric Norris wrote:

> Thanks, Jack! Now the only question is, is the KPA500 a great amp, or the
> greatest amp ever? I'm in the second camp.
>
> 73.5 Eric WD6DBM
>
> On Wed, Jul 8, 2020, 1:16 PM Jack Brindle <[hidden email]> wrote:
>
>> I can confirm that KPA500 V1.00 firmware, which was the first released,
>> had a max temperature of 90 degrees C. This has not been changed in any
>> subsequent code.
>>
>> As for the input power, the amplifier has improved over time. My original
>> prototype KPA500 requires power in the range described (about 35 - 40
>> watts), while my new one (just over a year old) needs about 20 or so watts.
>> Both are great amps!
>>
>> 73!
>> Jack, W6FB
>>
>>
>>> On Jul 8, 2020, at 1:00 PM, William Hammond via Elecraft <
>> [hidden email]> wrote:
>>> Hi Eric, My manual (revision B, 2011) that came with my SN 0149 says 90C
>> maximum, page14 in the specifications. It also says drive power 30-40
>> watts for 500 out and I have never beed even close to that, usually 22-26
>> watts drive.
>>> FYI,
>>> Bill-AK5X
>>>
>>>> On Jul 8, 2020, at 6:00 AM, Eric Norris <[hidden email]>
>> wrote:
>>>> I just read in the current KPA500 Manual that max heat sink temp is 90C.
>>>> Is this true for my first-year production KPA500? I seem to remember
>>>> somethink like 75C. I cant find my old manual.
>>>>
>>>> 73 Eric WD6DBM
>>>> ______________________________________________________________
>>>> 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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>>>
>>> This list hosted by: http://www.qsl.net
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>>> Message delivered to [hidden email]
>>
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Eric Norris-2

Re: KPA500 max heat sink temp?

Actually, I have, Rick. The KPA1500 is the second greatest amplifier in
the history of the solar system. It's a BattleBot, a monster, the
doomsday legal-limit amplifier. But the KPA500 is tiny, and so quiet that
I can run it in the same room where the XYL watches TV. My cat "Bubs"
McLovin does not even stir from his dreams of taking down a Cape Buffalo
when the KPA500 hits FAN3.

73 Eric WD6DBM

On Wed, Jul 8, 2020, 2:34 PM Rick Bates, NK7I <[hidden email]> wrote:

> Then you haven't used a KPA1500.
>
> Rick NK7I
>
>
> On 7/8/2020 2:11 PM, Eric Norris wrote:
> > Thanks, Jack! Now the only question is, is the KPA500 a great amp, or
> the
> > greatest amp ever? I'm in the second camp.
> >
> > 73.5 Eric WD6DBM
> >
> > On Wed, Jul 8, 2020, 1:16 PM Jack Brindle <[hidden email]> wrote:
> >
> >> I can confirm that KPA500 V1.00 firmware, which was the first released,
> >> had a max temperature of 90 degrees C. This has not been changed in any
> >> subsequent code.
> >>
> >> As for the input power, the amplifier has improved over time. My
> original
> >> prototype KPA500 requires power in the range described (about 35 - 40
> >> watts), while my new one (just over a year old) needs about 20 or so
> watts.
> >> Both are great amps!
> >>
> >> 73!
> >> Jack, W6FB
> >>
> >>
> >>> On Jul 8, 2020, at 1:00 PM, William Hammond via Elecraft <
> >> [hidden email]> wrote:
> >>> Hi Eric, My manual (revision B, 2011) that came with my SN 0149 says
> 90C
> >> maximum, page14 in the specifications. It also says drive power 30-40
> >> watts for 500 out and I have never beed even close to that, usually
> 22-26
> >> watts drive.
> >>> FYI,
> >>> Bill-AK5X
> >>>
> >>>> On Jul 8, 2020, at 6:00 AM, Eric Norris <[hidden email]>
> >> wrote:
> >>>> I just read in the current KPA500 Manual that max heat sink temp is
> 90C.
> >>>> Is this true for my first-year production KPA500? I seem to remember
> >>>> somethink like 75C. I cant find my old manual.
> >>>>
> >>>> 73 Eric WD6DBM
> >>>> ______________________________________________________________
> >>>> 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]
>

Rick Bates, NK7I

Re: KPA500 max heat sink temp?

I have both. I've had the KPA500 much longer of course and it's nice.
Small, concise and quiet, perfect for closest stations (tight spaces).

Having the KAT500 (essentially) built into one package with the 1500
watt amp (less cabling but one less antenna port too than the KAT500)
with legal (US) limit is awesome, meaning full range from 0.1-1500 watts
out (with overhead, not straining, don't ask ;-) oops).

Since I moved to strictly resonant antennas, the KPA1500 tuner is being
used only as an antenna switch, the fan noise isn't awful (the 12V 60A
power supply fan on the other hand... wow!), but since that 240V circuit
isn't on the house generator, when the power goes out, it'll be a quick
swap to put the KPA500/KAT500 back into play. It's nice to have options.

With the KPA500, one must still use finesse, with the KPA1500, one
shouts "Mongo hungry; feed Mongo!" (movie reference). I strongly
suspect that the KPA1500 will integrate so well into the K4 it'll simply
be amazing, outstanding, <add your superlative> (I'll find out later
this summer).

Each has it's place, if we ever get out of house arrest and back to
having DXPeditions. My logbook is beginning to sound like hungry
Mongo... band slots, while tasty, do not make a meal.

73,
Rick NK7I

On 7/8/2020 5:08 PM, Eric Norris wrote:

> Actually, I have, Rick. The KPA1500 is the second greatest amplifier
> in the history of the solar system. It's a BattleBot, a monster, the
> doomsday legal-limit amplifier. But the KPA500 is tiny, and so quiet
> that I can run it in the same room where the XYL watches TV. My cat
> "Bubs" McLovin does not even stir from his dreams of taking down a
> Cape Buffalo when the KPA500 hits FAN3.
>
> 73 Eric WD6DBM
>
> On Wed, Jul 8, 2020, 2:34 PM Rick Bates, NK7I <[hidden email]
> <mailto:[hidden email]>> wrote:
>
> Then you haven't used a KPA1500.
>
> Rick NK7I
>
>
> On 7/8/2020 2:11 PM, Eric Norris wrote:
> > Thanks, Jack! Now the only question is, is the KPA500 a great
> amp, or the
> > greatest amp ever? I'm in the second camp.
> >
> > 73.5 Eric WD6DBM
> >
> > On Wed, Jul 8, 2020, 1:16 PM Jack Brindle <[hidden email]
> <mailto:[hidden email]>> wrote:
> >
> >> I can confirm that KPA500 V1.00 firmware, which was the first
> released,
> >> had a max temperature of 90 degrees C. This has not been
> changed in any
> >> subsequent code.
> >>
> >> As for the input power, the amplifier has improved over time.
> My original
> >> prototype KPA500 requires power in the range described (about
> 35 - 40
> >> watts), while my new one (just over a year old) needs about 20
> or so watts.
> >> Both are great amps!
> >>
> >> 73!
> >> Jack, W6FB
> >>
> >>
> >>> On Jul 8, 2020, at 1:00 PM, William Hammond via Elecraft <
> >> [hidden email] <mailto:[hidden email]>> wrote:
> >>> Hi Eric, My manual (revision B, 2011) that came with my SN
> 0149 says 90C
> >> maximum, page14 in the specifications. It also says drive
> power 30-40
> >> watts for 500 out and I have never beed even close to that,
> usually 22-26
> >> watts drive.
> >>> FYI,
> >>> Bill-AK5X
> >>>
> >>>> On Jul 8, 2020, at 6:00 AM, Eric Norris
> <[hidden email] <mailto:[hidden email]>>
> >> wrote:
> >>>> I just read in the current KPA500 Manual that max heat sink
> temp is 90C.
> >>>> Is this true for my first-year production KPA500? I seem to
> remember
> >>>> somethink like 75C. I cant find my old manual.
> >>>>
> >>>> 73 Eric WD6DBM
> >>>> ______________________________________________________________
> >>>> Elecraft mailing list
> >>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> >>>> Help: http://mailman.qth.net/mmfaq.htm
> >>>> Post: mailto:[hidden email]
> <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] <mailto:[hidden email]>
> >>> ______________________________________________________________
> >>> Elecraft mailing list
> >>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> >>> Help: http://mailman.qth.net/mmfaq.htm
> >>> Post: mailto:[hidden email]
> <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]
> <mailto:[hidden email]>
> >>
> > ______________________________________________________________
> > Elecraft mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/elecraft
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: mailto:[hidden email]
> <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]
> <mailto:[hidden email]>
> ______________________________________________________________
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>

Edward R Cole

Re: KPA500 max heat sink temp?

In reply to this post by Eric Norris-2

Not a burning need, but I could see buying a KPA500 some day.

I have the K3/10 and KX3 which are both 12w output and drive my
KXPA100, nicely. It has the KXAT100 tuner.

If I decided to have high power on HF that might also mean an upgrade
in HF yagi (20-10m). I have an aged Hygain TH3mk4 which needs the
antenna tuner to match. Its the old trap design so might opt for a
SteppIR or a log-periodic, both of which need no tuning. 6-dBi gain
would be adequate, non-contester or DXer on HF.

Side Note to 6m ops: I am now monitoring 50.313 FT8, daily (with PSK
Reporter enabled).

73, Ed - KL7UW
http://www.kl7uw.com
Dubus-NA Business mail:
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