Elecraft

KPA1500 Fan Noise - Not An Issue

Classic

List

Threaded

15 messages Options

Don Butler

KPA1500 Fan Noise - Not An Issue

A post this afternoon refered to KPA1500 fan noise as an "issue" that might
need to be addressed. I personally think that is an unfair suggestion.
Fan noise with this amplifier is NOT an issue to me. I have made previous
comments and have also posted a video on this thread, and if I have given
the impression that fan noise is a problem in my shack I apologize, because
that is simply not the case.

Quite frankly, I think all the hubbub about KPA1500 fan noise is a huge
overreaction. The reality is that the fans will NEVER be required in most
operating situations. I've had my amplifier for three months now, and it
has gotten many hours of use. Typically, with the amp idling in standby as
I tune and complete occasional short CW QSOs, the fans NEVER do kick on.
And if they do they will rarely rise above Level 2. Levels 3, 4 and 5 may
be required during very heavy duty only, and, at least at my station, I
cannot foresee that happening more than 1 or 2 percent of the time. I have
manually selected level 3 on just two occasions, and have never had to use
levels 4 or 5. I personally believe that folks out there are fretting
over fan noise that may never occur.

IMHO the KPA1500 is a great amp. Amps are going to get hot. The more an
amp is put into transmit mode the hotter it's going to get. So it has to
be cooled. There's no free lunch. When my amp does get hot enough to
require speed level 3 or above I will simply put on my earphones and
continue to operate (I use earphones most of the time anyhow). As I
mentioned above, in the three months that I have owned this amplifier, I
have manually switched to level 3 just two times (once while CQing for hours
while running in a CW contest and once when I spent about 30 minutes chasing
a DX station in a major CW pileup).

To me, increased fan cooling capability is one of the KPA1500's uniquely
great features. Yes, the fans create noise, but they also rapidly cool the
heat sink (probably better than any other amplifier out there). But folks
seem to be more concerned about this noise thing when (I think) they should
really be appreciating the KPA1500's superior cooling capabilities.

I think we should get over this fixation on noise and just enjoy our
amplifiers.

As far as I'm concerned fan noise is NOT as issue with the KPA1500.

Don, N5LZ
KPA1500 S/N 45

______________________________________________________________
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: KPA1500 Fan Noise - Not An Issue

Thanks for your report. I am a future owner. Paid for it and am awaiting delivery. As a FT of KPA500, I cannot imagine the 1500 would be any less and in fact appears to be much more... as it should given the additional technology.

73,
Bill
K9YEQ

https://wrj-tech.com/

-----Original Message-----
From: [hidden email] <[hidden email]> On Behalf Of Don Butler
Sent: Sunday, June 3, 2018 6:33 PM
To: [hidden email]
Subject: [Elecraft] KPA1500 Fan Noise - Not An Issue

A post this afternoon refered to KPA1500 fan noise as an "issue" that might
need to be addressed. I personally think that is an unfair suggestion.
Fan noise with this amplifier is NOT an issue to me. I have made previous
comments and have also posted a video on this thread, and if I have given the impression that fan noise is a problem in my shack I apologize, because that is simply not the case.

Quite frankly, I think all the hubbub about KPA1500 fan noise is a huge overreaction. The reality is that the fans will NEVER be required in most
operating situations. I've had my amplifier for three months now, and it
has gotten many hours of use. Typically, with the amp idling in standby as
I tune and complete occasional short CW QSOs, the fans NEVER do kick on.
And if they do they will rarely rise above Level 2. Levels 3, 4 and 5 may
be required during very heavy duty only, and, at least at my station, I
cannot foresee that happening more than 1 or 2 percent of the time. I have
manually selected level 3 on just two occasions, and have never had to use
levels 4 or 5. I personally believe that folks out there are fretting
over fan noise that may never occur.

IMHO the KPA1500 is a great amp. Amps are going to get hot. The more an
amp is put into transmit mode the hotter it's going to get. So it has to
be cooled. There's no free lunch. When my amp does get hot enough to
require speed level 3 or above I will simply put on my earphones and continue to operate (I use earphones most of the time anyhow). As I mentioned above, in the three months that I have owned this amplifier, I have manually switched to level 3 just two times (once while CQing for hours while running in a CW contest and once when I spent about 30 minutes chasing a DX station in a major CW pileup).

To me, increased fan cooling capability is one of the KPA1500's uniquely great features. Yes, the fans create noise, but they also rapidly cool the
heat sink (probably better than any other amplifier out there). But folks
seem to be more concerned about this noise thing when (I think) they should really be appreciating the KPA1500's superior cooling capabilities.

I think we should get over this fixation on noise and just enjoy our amplifiers.

As far as I'm concerned fan noise is NOT as issue with the KPA1500.

Don, N5LZ
KPA1500 S/N 45

______________________________________________________________
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: KPA1500 Fan Noise - Not An Issue

In reply to this post by Don Butler

Well said, Don, and I agree. Its not an issue with me either. Even though its my first solid state amp I realize the need to cool it. They're already up to suggestingwater cooling. I think we need to talk about hydrogen cooling, something the radio room on the Enterprise from Star Trek might have, hi.
The future firmware change might ease some of the "issues" some may have. Even with that change I will still manually set the fan speed to 2 or maybe 3 duringheavy contesting depending on the situation at the time. I still prefer tube amps like my Acom 2000a but am glad I bought and own the kpa1500.

BillK3WJV

On Sunday, June 3, 2018, 7:36:52 PM EDT, Don Butler <[hidden email]> wrote:

A post this afternoon refered to KPA1500 fan noise as an "issue" that might
need to be addressed. I personally think that is an unfair suggestion.
Fan noise with this amplifier is NOT an issue to me. I have made previous
comments and have also posted a video on this thread, and if I have given
the impression that fan noise is a problem in my shack I apologize, because
that is simply not the case.

Quite frankly, I think all the hubbub about KPA1500 fan noise is a huge
overreaction. The reality is that the fans will NEVER be required in most
operating situations. I've had my amplifier for three months now, and it
has gotten many hours of use. Typically, with the amp idling in standby as
I tune and complete occasional short CW QSOs, the fans NEVER do kick on.
And if they do they will rarely rise above Level 2. Levels 3, 4 and 5 may
be required during very heavy duty only, and, at least at my station, I
cannot foresee that happening more than 1 or 2 percent of the time. I have
manually selected level 3 on just two occasions, and have never had to use
levels 4 or 5. I personally believe that folks out there are fretting
over fan noise that may never occur.

IMHO the KPA1500 is a great amp. Amps are going to get hot. The more an
amp is put into transmit mode the hotter it's going to get. So it has to
be cooled. There's no free lunch. When my amp does get hot enough to
require speed level 3 or above I will simply put on my earphones and
continue to operate (I use earphones most of the time anyhow). As I
mentioned above, in the three months that I have owned this amplifier, I
have manually switched to level 3 just two times (once while CQing for hours
while running in a CW contest and once when I spent about 30 minutes chasing
a DX station in a major CW pileup).

To me, increased fan cooling capability is one of the KPA1500's uniquely
great features. Yes, the fans create noise, but they also rapidly cool the
heat sink (probably better than any other amplifier out there). But folks
seem to be more concerned about this noise thing when (I think) they should
really be appreciating the KPA1500's superior cooling capabilities.

I think we should get over this fixation on noise and just enjoy our
amplifiers.

As far as I'm concerned fan noise is NOT as issue with the KPA1500.

Don, N5LZ
KPA1500 S/N 45

______________________________________________________________
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]

Richard Thorne-4

Re: KPA1500 Fan Noise - Not An Issue

In reply to this post by Don Butler

Don,

Thanks for the updated information. It's quite helpful.

For those of you that don't think that fan noise is a potential problem,
you need to understand my point of view on this.

I've tried very hard to get a good clean noise free signal to my speaker
or head phones.. This starts with a good antenna system followed by a
good ground system and chokes as needed to reduce any induced noise into
the system. i still have work do in this area.

It doesn't make much sense to get the above done, only to have the audio
portion of the signal interfered with.

So before I lay down significant $ for another device, I want to find
out all the pro's and con's for that device so I don't later regret the
decision.

In my case I'm not interested in getting a set of headphones (that
includes a boom mic) that clamps on to my head that causes discomfort.
If I'm going to use a set of headphones it will continue to be the
Yamaha CM-500. The mic is outstanding and it's the most comfortable
headset I've ever used. I use the headset for cw and ssb, but I prefer
to use my external speakers for RTTY with the volume low.

While I'm not all that interested in remoting the amp, I may end up
going this direction. I have the room to build a sound proofing wall
that can be located between my operating desk and external wall to the
shack where my entrance panel is. This may be a good option, if needed,
in order to have a quality piece of equipment in my shack.
I've spent time on my antenna system to mitigate noise, I may have to do
the same thing on the audio side.

So the folks who don't mind the extra fan noise (if in deed it exists)
fine, but understand where some of us are coming from that don't want to
deal with the noise (if in deed it exists).

At this time I'm still looking forward to taking delivery of the
KPA-1500 in the very near future.

Rich - N5ZC

On 6/3/2018 6:33 PM, Don Butler wrote:

> A post this afternoon refered to KPA1500 fan noise as an "issue" that might
> need to be addressed. I personally think that is an unfair suggestion.
> Fan noise with this amplifier is NOT an issue to me. I have made previous
> comments and have also posted a video on this thread, and if I have given
> the impression that fan noise is a problem in my shack I apologize, because
> that is simply not the case.
>
> Quite frankly, I think all the hubbub about KPA1500 fan noise is a huge
> overreaction. The reality is that the fans will NEVER be required in most
> operating situations. I've had my amplifier for three months now, and it
> has gotten many hours of use. Typically, with the amp idling in standby as
> I tune and complete occasional short CW QSOs, the fans NEVER do kick on.
> And if they do they will rarely rise above Level 2. Levels 3, 4 and 5 may
> be required during very heavy duty only, and, at least at my station, I
> cannot foresee that happening more than 1 or 2 percent of the time. I have
> manually selected level 3 on just two occasions, and have never had to use
> levels 4 or 5. I personally believe that folks out there are fretting
> over fan noise that may never occur.
>
> IMHO the KPA1500 is a great amp. Amps are going to get hot. The more an
> amp is put into transmit mode the hotter it's going to get. So it has to
> be cooled. There's no free lunch. When my amp does get hot enough to
> require speed level 3 or above I will simply put on my earphones and
> continue to operate (I use earphones most of the time anyhow). As I
> mentioned above, in the three months that I have owned this amplifier, I
> have manually switched to level 3 just two times (once while CQing for hours
> while running in a CW contest and once when I spent about 30 minutes chasing
> a DX station in a major CW pileup).
>
> To me, increased fan cooling capability is one of the KPA1500's uniquely
> great features. Yes, the fans create noise, but they also rapidly cool the
> heat sink (probably better than any other amplifier out there). But folks
> seem to be more concerned about this noise thing when (I think) they should
> really be appreciating the KPA1500's superior cooling capabilities.
>
> I think we should get over this fixation on noise and just enjoy our
> amplifiers.
>
> As far as I'm concerned fan noise is NOT as issue with the KPA1500.
>
> Don, N5LZ
> KPA1500 S/N 45
>
> ______________________________________________________________
> 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: KPA1500 Fan Noise - Not An Issue

Room acoustics play a big part of the "how loud" factor. Absorptive
materials applied to the walls an ceiling of a room, specially small
rooms, do reduce the build up of sound / noise emitted from fans and
blowers.

73

Bob, K4TAX

On 6/4/2018 10:04 AM, Richard Thorne wrote:

> Don,
>
> Thanks for the updated information. It's quite helpful.
>
> For those of you that don't think that fan noise is a potential
> problem, you need to understand my point of view on this.
>
> I've tried very hard to get a good clean noise free signal to my
> speaker or head phones.. This starts with a good antenna system
> followed by a good ground system and chokes as needed to reduce any
> induced noise into the system. i still have work do in this area.
>
> It doesn't make much sense to get the above done, only to have the
> audio portion of the signal interfered with.
>
> So before I lay down significant $ for another device, I want to find
> out all the pro's and con's for that device so I don't later regret
> the decision.
>
> In my case I'm not interested in getting a set of headphones (that
> includes a boom mic) that clamps on to my head that causes
> discomfort. If I'm going to use a set of headphones it will continue
> to be the Yamaha CM-500. The mic is outstanding and it's the most
> comfortable headset I've ever used. I use the headset for cw and ssb,
> but I prefer to use my external speakers for RTTY with the volume low.
>
> While I'm not all that interested in remoting the amp, I may end up
> going this direction. I have the room to build a sound proofing wall
> that can be located between my operating desk and external wall to the
> shack where my entrance panel is. This may be a good option, if
> needed, in order to have a quality piece of equipment in my shack.
> I've spent time on my antenna system to mitigate noise, I may have to
> do the same thing on the audio side.
>
> So the folks who don't mind the extra fan noise (if in deed it exists)
> fine, but understand where some of us are coming from that don't want
> to deal with the noise (if in deed it exists).
>
> At this time I'm still looking forward to taking delivery of the
> KPA-1500 in the very near future.
>
> Rich - N5ZC
>
> On 6/3/2018 6:33 PM, Don Butler wrote:
>> A post this afternoon refered to KPA1500 fan noise as an "issue" that
>> might
>> need to be addressed.   I personally think that is an unfair suggestion.
>> Fan noise with this amplifier is NOT an issue to me.   I have made
>> previous
>> comments and have also posted a video on this thread, and if I have
>> given
>> the impression that fan noise is a problem in my shack I apologize,
>> because
>> that is simply not the case.
>>    Quite frankly, I think all the hubbub about KPA1500 fan noise is a
>> huge
>> overreaction. The reality is that the fans will NEVER be required in
>> most
>> operating situations.   I've had my amplifier for three months now,
>> and it
>> has gotten many hours of use.   Typically, with the amp idling in
>> standby as
>> I tune and complete occasional short CW QSOs, the fans NEVER do kick on.
>> And if they do they will rarely rise above Level 2.   Levels 3, 4
>> and 5 may
>> be required during very heavy duty only, and, at least at my station, I
>> cannot foresee that happening more than 1 or 2 percent of the time.
>> I have
>> manually selected level 3 on just two occasions, and have never had
>> to use
>> levels 4 or 5.   I personally believe that folks out there are fretting
>> over fan noise that may never occur.
>> IMHO the KPA1500 is a great amp.   Amps are going to get hot. The
>> more an
>> amp is put into transmit mode the hotter it's going to get.   So it
>> has to
>> be cooled. There's no free lunch.   When my amp does get hot enough to
>> require speed level 3 or above I will simply put on my earphones and
>> continue to operate (I use earphones most of the time anyhow). As I
>> mentioned above, in the three months that I have owned this amplifier, I
>> have manually switched to level 3 just two times (once while CQing
>> for hours
>> while running in a CW contest and once when I spent about 30 minutes
>> chasing
>> a DX station in a major CW pileup).
>> To me, increased fan cooling capability is one of the KPA1500's
>> uniquely
>> great features. Yes, the fans create noise, but they also rapidly
>> cool the
>> heat sink (probably better than any other amplifier out there).   But
>> folks
>> seem to be more concerned about this noise thing when (I think) they
>> should
>> really be appreciating the KPA1500's superior cooling capabilities.
>> I think we should get over this fixation on noise and just enjoy our
>> amplifiers.
>>
>> As far as I'm concerned fan noise is NOT as issue with the KPA1500.
>>
>> Don, N5LZ
>> KPA1500 S/N 45
>>
>> ______________________________________________________________
>> 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]

Jim Brown-10

Re: KPA1500 Fan Noise - Not An Issue

On 6/4/2018 8:34 AM, Bob McGraw K4TAX wrote:
> Room acoustics play a big part of the "how loud" factor. Absorptive
> materials applied to the walls an ceiling of a room, specially small
> rooms, do reduce the build up of sound / noise emitted from fans and
> blowers.

YES! This is excellent advice. Indeed, the first place to put absorptive
material is on wall surfaces around the amp, treating other wall
surfaces can also help a lot. Hard surfaces contain the sound, causing
it to bounce around the room. Soft surfaces absorb the sound, causing it
to die out more quickly.

Mechanical coupling of vibration to the desk increases the audibility of
noise, so it can also help to isolate the amp from the shelf it is
sitting on.

Fan noise on the transmitted signal can be minimized in several ways,
all of which are pretty simple.

First, keep the mic close to your mouth -- sound falls off by 6dB per
doubling of distance. Boom mics, like the CM500, are great for this. For
best sound quality, I try to keep the mic an inch or two above and to
the side of my mouth. The principle is to maximize speech and minimize
noise -- a simple signal to noise problem.

Second, don't turn mic gain up higher than needed, and don't overdo
compression. This is the primary cause of excessive noise on transmitted
signals.

Third, set TXEQ to emphasize the speech range and de-emphasize other
sound. My guideline EQ settings do this -- max cut of the three lower
bands, 6 dB cut of the fourth band (400 Hz), and then get reports from a
careful listener.

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]

Bob McGraw - K4TAX

Re: KPA1500 Fan Noise - Not An Issue

One of my favorite methods of sound treatment is the products in the
link following: http://www.sonex-online.com/Pro%20Audio.htm

There are many other products, and many individuals use their own
creative means to be effective in sound absorption.

73

Bob, K4TAX

On 6/4/2018 1:00 PM, Jim Brown wrote:

> On 6/4/2018 8:34 AM, Bob McGraw K4TAX wrote:
>> Room acoustics play a big part of the "how loud" factor. Absorptive
>> materials applied to the walls an ceiling of a room, specially small
>> rooms, do reduce the build up of sound / noise emitted from fans and
>> blowers.
>
> YES! This is excellent advice. Indeed, the first place to put
> absorptive material is on wall surfaces around the amp, treating other
> wall surfaces can also help a lot. Hard surfaces contain the sound,
> causing it to bounce around the room. Soft surfaces absorb the sound,
> causing it to die out more quickly.
>
> Mechanical coupling of vibration to the desk increases the audibility
> of noise, so it can also help to isolate the amp from the shelf it is
> sitting on.
>
> Fan noise on the transmitted signal can be minimized in several ways,
> all of which are pretty simple.
>
> First, keep the mic close to your mouth -- sound falls off by 6dB per
> doubling of distance. Boom mics, like the CM500, are great for this.
> For best sound quality, I try to keep the mic an inch or two above and
> to the side of my mouth. The principle is to maximize speech and
> minimize noise -- a simple signal to noise problem.
>
> Second, don't turn mic gain up higher than needed, and don't overdo
> compression. This is the primary cause of excessive noise on
> transmitted signals.
>
> Third, set TXEQ to emphasize the speech range and de-emphasize other
> sound. My guideline EQ settings do this -- max cut of the three lower
> bands, 6 dB cut of the fourth band (400 Hz), and then get reports from
> a careful listener.
>
> 73, Jim K9YC
>

Elecraft mailing list

Re: KPA1500 Fan Noise - Not An Issue

While I appreciate all of the sound proofing suggestions, the old rule keeps coming back.: " Stop the source as much possible FIRST." I hate patches......
Mel, K6KBE

From: Bob McGraw K4TAX <[hidden email]>
To: [hidden email]
Sent: Monday, June 4, 2018 2:20 PM
Subject: Re: [Elecraft] KPA1500 Fan Noise - Not An Issue

One of my favorite methods of sound treatment is the products in the
link following: http://www.sonex-online.com/Pro%20Audio.htm

There are many other products, and many individuals use their own
creative means to be effective in sound absorption.

73

Bob, K4TAX

On 6/4/2018 1:00 PM, Jim Brown wrote:

______________________________________________________________
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]

Jim Brown-10

Re: KPA1500 Fan Noise - Not An Issue

That's fine if cost is no object. Acoustics is part of the problem --
ignore it at your peril. :)

73, Jim K9YC

On 6/4/2018 3:06 PM, Mel Farrer via Elecraft wrote:
> While I appreciate all of the sound proofing suggestions, the old rule keeps coming back.: " Stop the source as much possible FIRST." I hate patches......
> Mel, K6KBE

______________________________________________________________
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: KPA1500 Fan Noise - Not An Issue

A properly damped acoustic environment will enhance the SSB voice on the
air. While a poor acoustic environment will sound like crap, and no
amount of EQ , processing or microphone will correct the undesirable
artifacts.     Give some thoughts to improving your radio room
acoustics.   Even a drape hanging on a wall or doorway makes a
difference. And if you have a window, close the drapes to make an
improvement reducing reflections from the glass.   It helps on receiving
as well by reducing reflections {just like SWR} making for less
fatiguing listening.

73

Bob, K4TAX

On 6/4/2018 6:17 PM, Jim Brown wrote:

> That's fine if cost is no object. Acoustics is part of the problem --
> ignore it at your peril. :)
>
> 73, Jim K9YC
>
> On 6/4/2018 3:06 PM, Mel Farrer via Elecraft wrote:
>> While I appreciate all of the sound proofing suggestions, the old
>> rule keeps coming back.: " Stop the source as much possible FIRST."
>> I hate patches......
>> Mel, K6KBE
>
>
> ______________________________________________________________
> 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]

Paul Baldock

Re: KPA1500 Fan Noise - Not An Issue

In reply to this post by Elecraft mailing list

Can the KPA1500 run brick down 100% duty cycle at 1500W while
maintaining the temperature in a safe range? Anybody tried it?

- Paul

______________________________________________________________
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: KPA1500 Fan Noise - Not An Issue

In reply to this post by Jim Brown-10

Oh, I was just reminded of an ounce of prevention is worth a pound of cure. I think that ratio is 16 to 1. Only issue is look carefully at the application and plan accordingly or spend a lot of time and money trying to fix it.
Mel, K6KBE

From: Jim Brown <[hidden email]>
To: [hidden email]
Sent: Monday, June 4, 2018 4:19 PM
Subject: Re: [Elecraft] KPA1500 Fan Noise - Not An Issue

That's fine if cost is no object. Acoustics is part of the problem --
ignore it at your peril. :)

73, Jim K9YC

On 6/4/2018 3:06 PM, Mel Farrer via Elecraft wrote:
> While I appreciate all of the sound proofing suggestions, the old rule keeps coming back.: " Stop the source as much possible FIRST." I hate patches......
> Mel, K6KBE

______________________________________________________________
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]

WILLIE BABER

Re: KPA1500 Fan Noise - Not An Issue

In reply to this post by Don Butler

I imagine that if enough heat can be removed fast enough KPA1500 would run key-down forever at 1500 watts output. That is why fan levels 4 and 5 are so loud, to give those five minutes on (and take five minutes off) without the amplifier overheating and forcing a hard fault. Hard faults force KPA1500 into standby, to protect itself.

If you generate excessive forward power the amp will attenuate the excessive power and warn you with a yellow LED. If you continue to demand excessive power then you will get a hard fault and what sounds like a scream, along with a red LED. This must mean STOP!

"Dave, Dave. What are you doing Dave?"

73, Will, wj9b

CWops #1085
CWA Advisor levels II and III
http://cwops.org/

--------------------------------------------
On Tue, 6/5/18, Walter Underwood <[hidden email]> wrote:

Subject: Re: [Elecraft] KPA1500 Fan Noise - Not An Issue
To: "[hidden email]" <[hidden email]>
Date: Tuesday, June 5, 2018, 1:01 AM

I would recommend reading the
specs. As I remember, it is ICAS, five minutes on, five
minutes off. But you should check for yourself.

wunder
K6WRU
Walter Underwood
CM87wj
http://observer.wunderwood.org/ (my
blog)

> On Jun 4, 2018,
at 5:06 PM, Paul Baldock <[hidden email]>
wrote:
>
> Can the
KPA1500 run brick down 100% duty cycle at 1500W while
maintaining the temperature in a safe range? Anybody tried
it?
>
> - Paul
>
>
______________________________________________________________
> 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]

Edward R Cole

Re: KPA1500 Fan Noise - Not An Issue

In reply to this post by Don Butler

Frankly I agree with Bob-K4TAX:

If you ever have chance to visit the sound booth at either a
broadcast station or recording studio, note the use of acoustic tile.

The Super-Contest station of KL7RA (sk) is lined with acoustic tile
and you note immediately how quiet the room sounds (even with radios
turned off). Not sure how many of you knew Rich Strand but he was a
radio astronomy consultant to NASA, flying world-wide to "fix" things
at remote dish sites (thus his call sign).

Since I had also worked for NASA at Goldstone and at JPL, Rich and I
had many enjoyable conversations.

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

Jim Shepherd

Re: KPA1500 Fan Noise - Not An Issue

In reply to this post by Don Butler

Just get a weekly delivery of a large container of liquid nitrogen and rig
up a way to spray it on the heatsinks... It can be very quiet, it has a
large temperature difference, so it will be efficient, and it may drive the
chips into superconducting status which will further improve the efficiency.

Jim W6US
______________________________________________________________
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]