Re: [Elecraft] KPA-500 fan noise
For that very reason I tend to not share much of the things I have developed, modified, invented etc. I've gotten to the point my time is more valuable than trying to explain it. I'll just be quiet about the rest of the fun stuff I have working here ;) From: Wes (N7WS) w...@triconet.org To: elecraft@mailman.qth.net Sent: Wednesday, June 4, 2014 2:04 PM Subject: Re: [Elecraft] KPA-500 fan noise You mean the responses from the intrepid ham experimenters who have historically torn into their gear to improve it or the hand wringers who worship in the house of Elecraft? Those are rhetorical questions, we both know the answer:-) Wes N7WS Homebrewing since 1958 On 6/3/2014 7:11 PM, Harry Yingst via Elecraft wrote: Some of the responses here really make me shake my head. Have fun. I learned long ago to not live in fear __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to hlyin...@yahoo.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA-500 fan noise
And I just say what could possibly go wrong? Lol Sent from my Cricket smartphone Original message From: Jim Brown j...@audiosystemsgroup.com Date: 06/03/2014 21:43 (GMT-06:00) To: elecraft@mailman.qth.net Subject: Re: [Elecraft] KPA-500 fan noise On 6/3/2014 7:11 PM, Harry Yingst via Elecraft wrote: I learned long ago to not live in fear I learned long ago that many problems are far more complex than they appear. 73, Jim K9YC __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to w...@gt.rr.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA-500 fan noise
You mean the responses from the intrepid ham experimenters who have historically torn into their gear to improve it or the hand wringers who worship in the house of Elecraft? Those are rhetorical questions, we both know the answer:-) Wes N7WS Homebrewing since 1958 On 6/3/2014 7:11 PM, Harry Yingst via Elecraft wrote: Some of the responses here really make me shake my head. Have fun. I learned long ago to not live in fear __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA-500 fan noise
I would tend to believe that replacing the cheap fans with higher quality fans would be a improvement in design. If the K3 cannot handle what little extra current draw the fans have then I would certainly question the well engineered aspect of it. As in any product cost is a factor and I'm sure Elecraft has to weigh the cost associated with various parts. For many the noise will not bother them for others it will so for the ones who do find the additional noise bothersome they can simply swap out the fans for a higher quality fan and enjoy the reduction in fan noise. To my ears (and I'm partially deaf from when I was in the Navy) the stock fans in the K3 had a grating sound that added to the background noise. Replacing the fans was a worthwhile improvement and made copy easier. I'm not afraid of improving a design where there is room for improvement. From: Jim Brown j...@audiosystemsgroup.com To: elecraft@mailman.qth.net Sent: Monday, June 2, 2014 11:16 AM Subject: Re: [Elecraft] KPA-500 fan noise On 6/2/2014 7:56 AM, AG0N-3055 wrote: You could always try replacing the fan with a quieter fan. I would consider that myself, but only with one recommended by the good people at Elecraft. It is generally a bad idea to try to re-engineer a product, especially one that is well designed. In this case, I would consider it a really bad idea. 73, Jim K9YC __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to hlyin...@yahoo.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA-500 fan noise
I've never heard any of the fans (K3 or KPA500) except when I shut down the KPA500 for a short time. So I need no criteria :-) 73, Phil W7OX On 6/2/14, 7:55 PM, Richard L Diddams, Sr. wrote: My comment is not to K6GPW, but to the continuously number of postings regarding Fan Noise. 1) Would someone measure (quantify) the objectionable noise (using a sound meter) and report their dB findings. 2) Determine a sound level (measurement) that is acceptable (based upon normal ears). 3) Describe how / where the amplifier is located; possibly the amplifier is in a position where sound is reverberating off a wall, metal file cabinet, wooden or plastic shelf, (possibly the amplifier enclosure itself), etc.. 4) What is the noise specification of the fan in the amplifier provided by the manufacturer - is it being exceeded. 5) How loud is too loud - my ears or your ears? 6) Is there an industry standard for reference in measuring the KPA500 noise? Someone who is/are audio experts can provide a methodology on how to properly measure (fan) noise. Baseline fan noise must be measured in an environment where other artifacts are not influencing (amplifying) the real sound level and away from the operating station to obtain a true level of the fan noise. The measurement methodology must be capable of being duplicated by others with results within instrument accuracies. Next repeat measurements with the amplifier in the operating position. At least, at this time, one would know if there is an increase in fan noise level, if the noise increases, it probably isn't the fan. Possibly a simple solution to those with sensitive ears is placing sound absorbing material between the wall and amplifier, or a baffle above the amplifier slanting towards sound absorbing material. Or lastly, just suck it up and live with the noise. It very well could be, the artifact of undesirable fan noise can, only be resolved by usage of headphones or sell your amplifier - if the price is right, I'll buy yours! hi BTW, my KPA500 does not have an objectionable fan noise. I didn't use the word loud or soft: because I do not know what the definition of loud or soft may be! If I could borrow a noise meter, I'd measure my amplifier and let everyone what a desirable noise level should be! hi Owner of K1, K2, K3, KPA500, KAT500 and several other pieces of Elecraft products. 73, Dick - W7QHE/4 === Message: 9 Date: Mon, 02 Jun 2014 08:28:28 -0700 From: Fred Jensen k6...@foothill.net mailto:k6...@foothill.net To: elecraft@mailman.qth.net mailto:elecraft@mailman.qth.net Subject: Re: [Elecraft] KPA-500 fan noise Our Beverage Central is located in my shack. I was contemplating putting a heat exchanger on the KAP500 PA's and routing cold water from the drink fridge through it. I guess that would class as re-engineering? Haven't figured out how to get the plumbing out of the fridge, however. 73, Fred K6DGW - Northern California Contest Club - CU in the 2014 Cal QSO Party 4-5 Oct 2014 - www.cqp.org http://www.cqp.org/ On 6/2/2014 8:16 AM, Jim Brown wrote: On 6/2/2014 7:56 AM, AG0N-3055 wrote: You could always try replacing the fan with a quieter fan. I would consider that myself, but only with one recommended by the good people at Elecraft. It is generally a bad idea to try to re-engineer a product, especially one that is well designed. In thiscase, I would consider it a really bad idea. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA-500 fan noise
Hooray! BTW, what is the replacement fan you used in your K3? Wes N7WS On 6/3/2014 7:19 AM, Harry Yingst via Elecraft wrote: I would tend to believe that replacing the cheap fans with higher quality fans would be a improvement in design. If the K3 cannot handle what little extra current draw the fans have then I would certainly question the well engineered aspect of it. As in any product cost is a factor and I'm sure Elecraft has to weigh the cost associated with various parts. For many the noise will not bother them for others it will so for the ones who do find the additional noise bothersome they can simply swap out the fans for a higher quality fan and enjoy the reduction in fan noise. To my ears (and I'm partially deaf from when I was in the Navy) the stock fans in the K3 had a grating sound that added to the background noise. Replacing the fans was a worthwhile improvement and made copy easier. I'm not afraid of improving a design where there is room for improvement. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA-500 fan noise
I rag chew - long winded rag chew - and have never been insulted by the fan noises from the K3 or the KPA500. The noisiest they ever get is when I turn the KPA500 off - as it drains the power supply down. Certainly nothing like my previous tube type amp - providing over the air fan noise. The fan is set to NOR. My K-Line is on a computer desk like set of shelves - open to the back and about 18 inches from the wall. Perhaps the spacing to the wall has something to do with my lack of fan noise - also providing uncluttered fresh air for cooling. Bill W2BLC K-Line __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA-500 fan noise
On 6/3/2014 7:19 AM, Harry Yingst via Elecraft wrote: Replacing the fans was a worthwhile improvement and made copy easier. Something does not compute. The fan in my KPA500 is pretty quiet on RX, and only gets loud during long transmissions, continuing for a short time (a few seconds) after that. How does a fan that is noisy only on TX make copy difficult on RX? Another thing that doesn't compute is that a lot of the noise I'm hearing is air flow. Perhaps the replacement fan is running slower, which would reduce air flow, which would reduce cooling. Again, I would approach all of this with great caution. Cooling of power devices is as important an element of the design of amplifier as any of the rest of the circuitry. I think it's a mistake to think that we hear the fan because it's a cheap or inferior one. We hear it because it's working. 73, Jim K9YC __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA-500 fan noise
As I stated I do Not have a KPA500 It is in the future plans but I need to get some antenna work done first. As I stated I replaced the Fans in my K3 I went with the Noctua brand because they are known for making a quality fan that is very quiet. New Fan: Noctua NF-A6x25 FLX Airflow: 17 cfm (29.2 m3h converted to cfm) Noise: 19.3db Speed: 3000 RPM (at 12 v) Static Pressure: 2.18 mm Current: 120 mA (.12 A) Original Fan: UTEC AT6015L-12L2B-ND2 Airflow: 15.4 cmf at 24.8db Noise 24.8 Speed 3000 RPM (at 12v) Static Pressure: 2.21mm Current 100 mA Yes I hear the air rushing but not the bearings From: Jim Brown j...@audiosystemsgroup.com To: elecraft@mailman.qth.net Sent: Tuesday, June 3, 2014 2:21 PM Subject: Re: [Elecraft] KPA-500 fan noise On 6/3/2014 7:19 AM, Harry Yingst via Elecraft wrote: Replacing the fans was a worthwhile improvement and made copy easier. Something does not compute. The fan in my KPA500 is pretty quiet on RX, and only gets loud during long transmissions, continuing for a short time (a few seconds) after that. How does a fan that is noisy only on TX make copy difficult on RX? Another thing that doesn't compute is that a lot of the noise I'm hearing is air flow. Perhaps the replacement fan is running slower, which would reduce air flow, which would reduce cooling. Again, I would approach all of this with great caution. Cooling of power devices is as important an element of the design of amplifier as any of the rest of the circuitry. I think it's a mistake to think that we hear the fan because it's a cheap or inferior one. We hear it because it's working. 73, Jim K9YC __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to hlyin...@yahoo.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA-500 fan noise
Do you have the full design parameters for the KPA500 cooling, air flow required at specific temperatures to protect the MOSFETs, current and voltage capable of being delivered by the KPA500 circuits to the fan at each of 3 fan speeds? I certainly do not have those parameters. That information would be required to make any intelligent swap of the fan. I would not know what parameters would qualify a fan to be of higher quality than what is in there already- Greater air flow usually means more noise, and could mean more current draw. A lower fan speed would be less noisy, but would likely reduce the air flow and cause greater heating of the MOSFETs. I do not think changing the fan would be a task to be taken lightly, there are too many factors at play. Sending the KPA500 back to Elecraft because the 'new improved' fan needed more current than the KPA500 could supply, or sending it back to change the PA sandwich after installing a slower fan (or one with a lower blade pitch) that was more quiet, but failed to move enough air could become an expensive task. 73, Don W3FPR On 6/3/2014 10:19 AM, Harry Yingst via Elecraft wrote: I would tend to believe that replacing the cheap fans with higher quality fans would be a improvement in design. If the K3 cannot handle what little extra current draw the fans have then I would certainly question the well engineered aspect of it. As in any product cost is a factor and I'm sure Elecraft has to weigh the cost associated with various parts. For many the noise will not bother them for others it will so for the ones who do find the additional noise bothersome they can simply swap out the fans for a higher quality fan and enjoy the reduction in fan noise. To my ears (and I'm partially deaf from when I was in the Navy) the stock fans in the K3 had a grating sound that added to the background noise. Replacing the fans was a worthwhile improvement and made copy easier. I'm not afraid of improving a design where there is room for improvement. From: Jim Brown j...@audiosystemsgroup.com To: elecraft@mailman.qth.net Sent: Monday, June 2, 2014 11:16 AM Subject: Re: [Elecraft] KPA-500 fan noise On 6/2/2014 7:56 AM, AG0N-3055 wrote: You could always try replacing the fan with a quieter fan. I would consider that myself, but only with one recommended by the good people at Elecraft. It is generally a bad idea to try to re-engineer a product, especially one that is well designed. In this case, I would consider it a really bad idea. 73, Jim K9YC __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to hlyin...@yahoo.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to w3...@embarqmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA-500 fan noise
Some of the responses here really make me shake my head. Have fun. I learned long ago to not live in fear From: Don Wilhelm w3...@embarqmail.com To: elecraft@mailman.qth.net Sent: Tuesday, June 3, 2014 5:20 PM Subject: Re: [Elecraft] KPA-500 fan noise Do you have the full design parameters for the KPA500 cooling, air flow required at specific temperatures to protect the MOSFETs, current and voltage capable of being delivered by the KPA500 circuits to the fan at each of 3 fan speeds? I certainly do not have those parameters. That information would be required to make any intelligent swap of the fan. I would not know what parameters would qualify a fan to be of higher quality than what is in there already- Greater air flow usually means more noise, and could mean more current draw. A lower fan speed would be less noisy, but would likely reduce the air flow and cause greater heating of the MOSFETs. I do not think changing the fan would be a task to be taken lightly, there are too many factors at play. Sending the KPA500 back to Elecraft because the 'new improved' fan needed more current than the KPA500 could supply, or sending it back to change the PA sandwich after installing a slower fan (or one with a lower blade pitch) that was more quiet, but failed to move enough air could become an expensive task. 73, Don W3FPR On 6/3/2014 10:19 AM, Harry Yingst via Elecraft wrote: I would tend to believe that replacing the cheap fans with higher quality fans would be a improvement in design. If the K3 cannot handle what little extra current draw the fans have then I would certainly question the well engineered aspect of it. As in any product cost is a factor and I'm sure Elecraft has to weigh the cost associated with various parts. For many the noise will not bother them for others it will so for the ones who do find the additional noise bothersome they can simply swap out the fans for a higher quality fan and enjoy the reduction in fan noise. To my ears (and I'm partially deaf from when I was in the Navy) the stock fans in the K3 had a grating sound that added to the background noise. Replacing the fans was a worthwhile improvement and made copy easier. I'm not afraid of improving a design where there is room for improvement. From: Jim Brown j...@audiosystemsgroup.com To: elecraft@mailman.qth.net Sent: Monday, June 2, 2014 11:16 AM Subject: Re: [Elecraft] KPA-500 fan noise On 6/2/2014 7:56 AM, AG0N-3055 wrote: You could always try replacing the fan with a quieter fan. I would consider that myself, but only with one recommended by the good people at Elecraft. It is generally a bad idea to try to re-engineer a product, especially one that is well designed. In this case, I would consider it a really bad idea. 73, Jim K9YC __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to hlyin...@yahoo.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to w3...@embarqmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to hlyin...@yahoo.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA-500 fan noise
Harry, Harry, I didn't see this this email until just now -- it got stuck in my spam filter. The subject line says KPA-500, so that's what I was talking about. From what you've written here, it does, indeed, sound like you/ve done a pretty good engineering job. 73, Jim K9YC On 6/3/2014 12:17 PM, Harry Yingst wrote: As I stated I do Not have a KPA500 It is in the future plans but I need to get some antenna work done first. As I stated I replaced the Fans in my K3 I went with the Noctua brand because they are known for making a quality fan that is very quiet. New Fan: Noctua NF-A6x25 FLX Airflow: 17 cfm (29.2 m3h converted to cfm) Noise: 19.3db Speed: 3000 RPM (at 12 v) Static Pressure: 2.18 mm Current: 120 mA (.12 A) Original Fan: UTEC AT6015L-12L2B-ND2 Airflow: 15.4 cmf at 24.8db Noise 24.8 Speed 3000 RPM (at 12v) Static Pressure: 2.21mm Current 100 mA Yes I hear the air rushing but not the bearings *From:* Jim Brown j...@audiosystemsgroup.com *To:* elecraft@mailman.qth.net *Sent:* Tuesday, June 3, 2014 2:21 PM *Subject:* Re: [Elecraft] KPA-500 fan noise On 6/3/2014 7:19 AM, Harry Yingst via Elecraft wrote: Replacing the fans was a worthwhile improvement and made copy easier. Something does not compute. The fan in my KPA500 is pretty quiet on RX, and only gets loud during long transmissions, continuing for a short time (a few seconds) after that. How does a fan that is noisy only on TX make copy difficult on RX? Another thing that doesn't compute is that a lot of the noise I'm hearing is air flow. Perhaps the replacement fan is running slower, which would reduce air flow, which would reduce cooling. Again, I would approach all of this with great caution. Cooling of power devices is as important an element of the design of amplifier as any of the rest of the circuitry. I think it's a mistake to think that we hear the fan because it's a cheap or inferior one. We hear it because it's working. 73, Jim K9YC __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net http://www.qsl.net/ Please help support this email list: http://www.qsl.net/donate.html Message delivered to hlyin...@yahoo.com mailto:hlyin...@yahoo.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA-500 fan noise
Thanks to all who replied. If I did not have to cut a hole in the sheet rock, I would install a dryer vent!! I think I will try setting the fan to a minimum speed as suggested and see how that works out keeping the air moving all the time. 73s Jim, W4ATK __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA-500 fan noise
You could always try replacing the fan with a quieter fan. I do not have the KPA500 (Yet) but I did replace both the Fans on The K3 with Fans from Noctua. They are a lot quieter, The only downside is the color of the Fans, but not a big deal since they are in the back From: Jim Rogers jim.w4...@gmail.com To: elecraft@mailman.qth.net Sent: Monday, June 2, 2014 7:26 AM Subject: Re: [Elecraft] KPA-500 fan noise Thanks to all who replied. If I did not have to cut a hole in the sheet rock, I would install a dryer vent!! I think I will try setting the fan to a minimum speed as suggested and see how that works out keeping the air moving all the time. 73s Jim, W4ATK __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to hlyin...@yahoo.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA-500 fan noise
On Mon, 2 Jun 2014 06:05:22 -0700 (PDT), Harry Yingst via Elecraft wrote: You could always try replacing the fan with a quieter fan. I would consider that myself, but only with one recommended by the good people at Elecraft. The fan in the KPA is VERY loud when it hits the last two speeds. Warp and Turbo Warp would wake my wife in the next room if she was a light sleeper, although I virtually never get it up that warm. It was just my short excursion on 6M FM that really got it up there fast. My issue isn't with the fan operation, although I wish it would come on just a bit earlier than it does. My issue is with the sound level out of this particular fan. It's a screaming banshee when it gets up there at speed. It's a very raw sound, not the sound of air moving, but of a high speed motor. My only hesitation with putting a different fan in it would be compatibility with the speed control circuitry. I just won't do it, especially under warranty, without Elecraft's recommendation and blessing. They've got a good product and I want to keep it that way. Typing this up raised my curiosity and I went to the shack and ran a control test into my Bird load. I set my rig at 10W on 52.525 FM, which gives me 200W output. With manual fan control, I made sure the amp was cooled to 33C as a starting point, and then set the fan back to NORmal setting. I keyed the rig on FM at the (unmeasured) 10W setting, and sat back to see what it did. It took 75 seconds to reach 70C. At which point, the fan is at 5, a rather noisy speed. It seemed to level out at 77-78C for a bit and then went to 80C at 4:50 minutes. I ended the test at that point. At 80, the fan went to 6, the highest speed, screaming away. With this test, I'm confident that it would probably handle anything I would ever do to it in normal operation, especially given the fact that I'm not dumb enough to do that test at 500W output. :o) I think the fan does a pretty good job, but do wish it was quieter. I never hit those higher speeds, except in test conditions like this. My normal use has it hitting 70C only on the rarest of occasions. Gary -- http://ag0n.net 3055: http://ag0n.net/irlp/3055 NodeOp Help Page: http://ag0n.net/irlp __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA-500 fan noise
On 6/2/2014 7:56 AM, AG0N-3055 wrote: You could always try replacing the fan with a quieter fan. I would consider that myself, but only with one recommended by the good people at Elecraft. It is generally a bad idea to try to re-engineer a product, especially one that is well designed. In this case, I would consider it a really bad idea. 73, Jim K9YC __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA-500 fan noise
Our Beverage Central is located in my shack. I was contemplating putting a heat exchanger on the KAP500 PA's and routing cold water from the drink fridge through it. I guess that would class as re-engineering? Haven't figured out how to get the plumbing out of the fridge, however. 73, Fred K6DGW - Northern California Contest Club - CU in the 2014 Cal QSO Party 4-5 Oct 2014 - www.cqp.org On 6/2/2014 8:16 AM, Jim Brown wrote: On 6/2/2014 7:56 AM, AG0N-3055 wrote: You could always try replacing the fan with a quieter fan. I would consider that myself, but only with one recommended by the good people at Elecraft. It is generally a bad idea to try to re-engineer a product, especially one that is well designed. In this case, I would consider it a really bad idea. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA-500 fan noise
I would hate to think what would happen if a water line breaks. Why not duct the air from a portable AC unit to the KPA-500. Then when the ducting breaks you won't have water all over the place... just cool air. Seriously folks, any chance the exhaust air from the KPA is being fed back into the air intake for the KPA? That will heat things up in a hurry. Maybe outside air (depending where you live) ducted to the KPA would keep things cooler. Failing that just empty the contents of the beverage cooler into your stomach and after a while the whole room will be spinning. The fans will be still running but you won't notice. 73 Fred, AE6QL -Original Message- From: Fred Jensen k6...@foothill.net Sent: Jun 2, 2014 8:28 AM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] KPA-500 fan noise Our Beverage Central is located in my shack. I was contemplating putting a heat exchanger on the KAP500 PA's and routing cold water from the drink fridge through it. I guess that would class as re-engineering? Haven't figured out how to get the plumbing out of the fridge, however. 73, Fred K6DGW - Northern California Contest Club - CU in the 2014 Cal QSO Party 4-5 Oct 2014 - www.cqp.org On 6/2/2014 8:16 AM, Jim Brown wrote: On 6/2/2014 7:56 AM, AG0N-3055 wrote: You could always try replacing the fan with a quieter fan. I would consider that myself, but only with one recommended by the good people at Elecraft. It is generally a bad idea to try to re-engineer a product, especially one that is well designed. In this case, I would consider it a really bad idea. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to fptowns...@earthlink.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA-500 fan noise
you guys add one of these less strain on the fan and ur ears Bob K3DJC http://en.wikipedia.org/wiki/Thermoelectric_cooling n Mon, 2 Jun 2014 08:46:45 -0700 (GMT-07:00) Fred Townsend fptowns...@earthlink.net writes: I would hate to think what would happen if a water line breaks. Why not duct the air from a portable AC unit to the KPA-500. Then when the ducting breaks you won't have water all over the place... just cool air. Seriously folks, any chance the exhaust air from the KPA is being fed back into the air intake for the KPA? That will heat things up in a hurry. Maybe outside air (depending where you live) ducted to the KPA would keep things cooler. Failing that just empty the contents of the beverage cooler into your stomach and after a while the whole room will be spinning. The fans will be still running but you won't notice. 73 Fred, AE6QL -Original Message- From: Fred Jensen k6...@foothill.net Sent: Jun 2, 2014 8:28 AM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] KPA-500 fan noise Our Beverage Central is located in my shack. I was contemplating putting a heat exchanger on the KAP500 PA's and routing cold water from the drink fridge through it. I guess that would class as re-engineering? Haven't figured out how to get the plumbing out of the fridge, however. 73, Fred K6DGW - Northern California Contest Club - CU in the 2014 Cal QSO Party 4-5 Oct 2014 - www.cqp.org On 6/2/2014 8:16 AM, Jim Brown wrote: On 6/2/2014 7:56 AM, AG0N-3055 wrote: You could always try replacing the fan with a quieter fan. I would consider that myself, but only with one recommended by the good people at Elecraft. It is generally a bad idea to try to re-engineer a product, especially one that is well designed. In this case, I would consider it a really bad idea. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to fptowns...@earthlink.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to riese-k3...@juno.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA-500 fan noise
If you set fan speed to Level 1 in the first place, it will run continuously and avoid wide temperature variations. I can work pileups in RTTY at 500W and the fan goes into Level 2 on rare occasions and for a short time only. IMHO, the NORmal setting is not the best one. Level 1 (constant) is very quiet and a better choice to protect the Mosfets. 73 Richard - HB9ANM __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA-500 fan noise
How would that work Bob? Actually Peltier junctions do not create cold. They move heat and then the distance the heat is moved is less than a quarter inch and you end up with more heat than you started with. BTW you need a heat sink for the back side of the Peltier. Back to square one. You can get more cooling from an ice cube. 73 Fred, AE6QL -Original Message- From: riese-k3...@juno.com Sent: Jun 2, 2014 9:29 AM To: fptowns...@earthlink.net Cc: k6...@foothill.net, elecraft@mailman.qth.net Subject: Re: [Elecraft] KPA-500 fan noise you guys add one of these less strain on the fan and ur ears Bob K3DJC http://en.wikipedia.org/wiki/Thermoelectric_cooling n Mon, 2 Jun 2014 08:46:45 -0700 (GMT-07:00) Fred Townsend fptowns...@earthlink.net writes: I would hate to think what would happen if a water line breaks. Why not duct the air from a portable AC unit to the KPA-500. Then when the ducting breaks you won't have water all over the place... just cool air. Seriously folks, any chance the exhaust air from the KPA is being fed back into the air intake for the KPA? That will heat things up in a hurry. Maybe outside air (depending where you live) ducted to the KPA would keep things cooler. Failing that just empty the contents of the beverage cooler into your stomach and after a while the whole room will be spinning. The fans will be still running but you won't notice. 73 Fred, AE6QL -Original Message- From: Fred Jensen k6...@foothill.net Sent: Jun 2, 2014 8:28 AM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] KPA-500 fan noise Our Beverage Central is located in my shack. I was contemplating putting a heat exchanger on the KAP500 PA's and routing cold water from the drink fridge through it. I guess that would class as re-engineering? Haven't figured out how to get the plumbing out of the fridge, however. 73, Fred K6DGW - Northern California Contest Club - CU in the 2014 Cal QSO Party 4-5 Oct 2014 - www.cqp.org On 6/2/2014 8:16 AM, Jim Brown wrote: On 6/2/2014 7:56 AM, AG0N-3055 wrote: You could always try replacing the fan with a quieter fan. I would consider that myself, but only with one recommended by the good people at Elecraft. It is generally a bad idea to try to re-engineer a product, especially one that is well designed. In this case, I would consider it a really bad idea. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to fptowns...@earthlink.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to riese-k3...@juno.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA-500 fan noise
__ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA-500 fan noise
Let's end this thread for now, since the original poster has had his query answered. (And in the interest of keeping list volume under control.) 73, Eric List moderator elecraft.com On 6/2/2014 10:21 AM, Fred Townsend wrote: How would that work Bob? Actually Peltier junctions do not create cold. They move heat and then the distance the heat is moved is less than a quarter inch and you end up with more heat than you started with. BTW you need a heat sink for the back side of the Peltier. Back to square one. You can get more cooling from an ice cube. 73 Fred, AE6QL __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA-500 fan noise
My comment is not to K6GPW, but to the continuously number of postings regarding Fan Noise. 1) Would someone measure (quantify) the objectionable noise (using a sound meter) and report their dB findings. 2) Determine a sound level (measurement) that is acceptable (based upon normal ears). 3) Describe how / where the amplifier is located; possibly the amplifier is in a position where sound is reverberating off a wall, metal file cabinet, wooden or plastic shelf, (possibly the amplifier enclosure itself), etc.. 4) What is the noise specification of the fan in the amplifier provided by the manufacturer - is it being exceeded. 5) How loud is too loud - my ears or your ears? 6) Is there an industry standard for reference in measuring the KPA500 noise? Someone who is/are audio experts can provide a methodology on how to properly measure (fan) noise. Baseline fan noise must be measured in an environment where other artifacts are not influencing (amplifying) the real sound level and away from the operating station to obtain a true level of the fan noise. The measurement methodology must be capable of being duplicated by others with results within instrument accuracies. Next repeat measurements with the amplifier in the operating position. At least, at this time, one would know if there is an increase in fan noise level, if the noise increases, it probably isn't the fan. Possibly a simple solution to those with sensitive ears is placing sound absorbing material between the wall and amplifier, or a baffle above the amplifier slanting towards sound absorbing material. Or lastly, just suck it up and live with the noise. It very well could be, the artifact of undesirable fan noise can, only be resolved by usage of headphones or sell your amplifier - if the price is right, I'll buy yours! hi BTW, my KPA500 does not have an objectionable fan noise. I didn't use the word loud or soft: because I do not know what the definition of loud or soft may be! If I could borrow a noise meter, I'd measure my amplifier and let everyone what a desirable noise level should be! hi Owner of K1, K2, K3, KPA500, KAT500 and several other pieces of Elecraft products. 73, Dick - W7QHE/4 === Message: 9 Date: Mon, 02 Jun 2014 08:28:28 -0700 From: Fred Jensen k6...@foothill.net mailto:k6...@foothill.net To: elecraft@mailman.qth.net mailto:elecraft@mailman.qth.net Subject: Re: [Elecraft] KPA-500 fan noise Our Beverage Central is located in my shack. I was contemplating putting a heat exchanger on the KAP500 PA's and routing cold water from the drink fridge through it. I guess that would class as re-engineering? Haven't figured out how to get the plumbing out of the fridge, however. 73, Fred K6DGW - Northern California Contest Club - CU in the 2014 Cal QSO Party 4-5 Oct 2014 - www.cqp.org http://www.cqp.org/ On 6/2/2014 8:16 AM, Jim Brown wrote: On 6/2/2014 7:56 AM, AG0N-3055 wrote: You could always try replacing the fan with a quieter fan. I would consider that myself, but only with one recommended by the good people at Elecraft. It is generally a bad idea to try to re-engineer a product, especially one that is well designed. In thiscase, I would consider it a really bad idea. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA-500 fan noise
On 6/2/2014 7:55 PM, Richard L Diddams, Sr. wrote: My comment is not to K6GPW, but to the continuously number of postings regarding Fan Noise. Far more than necessary, IMO. Dick, the fan speed is adjusted by the control system based on temperature of the output devices, which you can monitor from the front panel. The fan speed gradually increases as the temperature passes lower temperature thresholds, but it really kicks into high gear at about 71 degrees C. If you want to hear what this sounds like, put a brick on the key and crank the amp to rated power for a minute or so. Depending on ambient and air flow in your shack, you'll hear it kick in, and if you have the instrumentation to do so, can measure it yourself. My fan kicks in roughly 40-45 seconds into a keydown transmission on 6M, and very occasionally, briefly, when I'm RTTY contesting, calling CQ near the end of the contest with few responses. In normal contesting, where you're sitting on a frequency and running stations at several a minute, the duty cycle is low enough that the high fan speed rarely kicks in. Could the noise level be reduced by some design advice from a good acoustic consultant? Sure. I can recommend several who work on making HVAC systems in theaters and concert halls dead quiet. How much cost would you like to add to your KPA500? The sound pressure level at that high is nothing more than annoying, certainly nothing to be alarmed about from a hearing damage point of view, and it's a lot less annoying if you're wearing cans. And for keydown modes like AM, FM, PSK, and RTTY, there's even a side benefit -- when the fan speeds up, you've probably been going on too long about nothing, so it works to prevent you from boring the other member(s) of the QSO. 73, Jim K9YC __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
[Elecraft] KPA-500 fan noise
I have been running some RTTY on 17M and FSK-441 on 6M meteor scatter, both of which have full period signals for 30 seconds or so. I have reduced power to 250W, but by the end of a transmissions the fan has gone to 747 short field take off mode at about 71C. Am I missing something here or is this normal? JIm, W4ATK __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA-500 fan noise
Am I missing something here or is this normal? Sounds normal for mine. I've recently had mine on 52.525 in an FM QSO. I ended up at about 250W with short transmissions. That didn't surprise me much at all, because my KPA seems to produce quite a bit of heat on six meters anyway. Hit the dummy load and do some continuous carrier testing and see how long it takes to hit high speed. It won't take long. That's one screaming fan. By the way, you can sample those speeds just by going to the menu and changing the fan control setting. That menu item sets the minimum speed the fan will run (auto = off when below threshold). One thing you might try is to set the fan to the first or second speed (not auto) when you're operating those modes. That let's the fan run all the time at the speed you set, which allows it to cool in receive mode when it might normally kick down to the off mode until you key the next time. Don't miss understand, the fan control menu sets the MINIMUM speed the fan runs. It still kicks up faster for warmer operation. Gary -- Web: http://ag0n.net NodeOp Page: http://ag0n.net/irlp Node 3055: http://ag0n.net/irlp/3055 __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA-500 fan noise
On 6/1/2014 5:59 PM, AG0N-3055 wrote: Sounds normal for mine. Yes, quite normal. The KPA500 is very well protected, while still allowing as much power output as possible. I do lots of RTTY contesting on HF, and JT65 on several bands, including 6M. Depending on the ambient temperature in the shack, the fan kicks into high gear after about 40 seconds, but the power remains at maximum. I ran a beta KPA500 for a RTTY contest weekend, with instructions to run it with all the lights lit. I did, with no issues, and that's how I've always run it. BTW -- with many classes of power amps, greatest dissipation is not at full power, but at some lower power level, and it is my understanding this is true with the KPA500. So backing off TX power probably isn't necessary, and if it is, the KPA500 will do it on its own. 73, Jim K9YC __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
[Elecraft] KPA 500 Fan Noise
Rich, You did not specify if your were on SSB or CW. There is no problem when on SSB. The real issue is when on CW or RTTY. The constant cycling and roar of the last fan speed is very unnerving. Toby W4CAk __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] KPA 500 Fan Noise
Noise canceling headphones might help. I got some for when our ARES/RACES group works events like parades. I found them useful for airplane trips. In my shack I have to deal with noise from refrigerators, washing machines, driers and dishwashers. They help there too. Cheers - Bill, AE6JV --- Bill Frantz| gets() remains as a monument | Periwinkle (408)356-8506 | to C's continuing support of | 16345 Englewood Ave www.pwpconsult.com | buffer overruns. | Los Gatos, CA 95032 __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] KPA 500 Fan Noise
Don, Feel free to share it here. 73, Eric www.elecraft.com _..._ On Nov 6, 2012, at 2:34 PM, donehrl...@q.com donehrl...@q.com wrote: Toby, I am far more sensitive to fan noise than most folks and have spent a lot of time making my KPA500 much quieter by modifying it and by other means. This topic is probably not of interest to most on this list because, compared to most amps, the KPA500 is NOT loud (and many have said it is much quieter). Contact me off list and I will be happy to share my experience with you. Don K7FJ __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
[Elecraft] KPA 500 Fan Noise
I have had the amp now about a year. The cooling fan is just fine when using SSB, but when on cw and running a while at full output, the fan comes on and sounds like it is going to take off from the table. It is really loud I have the fan speed set to 1, but wonder what others are doing to quieten the fan a little bit, or what fan speed you have the amp set to. OR WHATEVER Toby W4CAK __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] KPA 500 Fan Noise
Toby, I am far more sensitive to fan noise than most folks and have spent a lot of time making my KPA500 much quieter by modifying it and by other means. This topic is probably not of interest to most on this list because, compared to most amps, the KPA500 is NOT loud (and many have said it is much quieter). Contact me off list and I will be happy to share my experience with you. Don K7FJ I have had the amp now about a year. The cooling fan is just fine when using SSB, but when on cw and running a while at full output, the fan comes on and sounds like it is going to take off from the table. It is really loud I have the fan speed set to 1, but wonder what others are doing to quieten the fan a little bit, or what fan speed you have the amp set to. OR WHATEVER Toby W4CAK __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] KPA 500 Fan Noise
Actually, I for one would like to know how you did it. Just because a select few don't care some of us do. Please share with us all. 73, Tim Herrick, KQ8M Charter Member North Coast Contesters k...@kq8m.com AR-Cluster V6 kq8m.no-ip.org User Ports: 23, 7373 with local skimmer, 7374 without local skimmer Server Ports: V6 3607, V4 Active 3605, V4 Passive 3606 -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of donehrl...@q.com Sent: Tuesday, November 06, 2012 5:34 PM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] KPA 500 Fan Noise Toby, I am far more sensitive to fan noise than most folks and have spent a lot of time making my KPA500 much quieter by modifying it and by other means. This topic is probably not of interest to most on this list because, compared to most amps, the KPA500 is NOT loud (and many have said it is much quieter). Contact me off list and I will be happy to share my experience with you. Don K7FJ I have had the amp now about a year. The cooling fan is just fine when using SSB, but when on cw and running a while at full output, the fan comes on and sounds like it is going to take off from the table. It is really loud I have the fan speed set to 1, but wonder what others are doing to quieten the fan a little bit, or what fan speed you have the amp set to. OR WHATEVER Toby W4CAK __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] KPA 500 Fan Noise and cooling performance
Folks, this thread is drifting too far afield. Let's end the general fan discussion at this time. In the future, please resist the urge to post on OT threads like this when there are already a lot of responses in a short period, like this one. While OT threads are allowed, we ask that people resist the urge to prolong them, in the interest of improving the list signal to noise level. 73, Eric Elecraft List Manager and moderator www.elecraft.com _..._ On Jun 19, 2012, at 9:46 PM, Ron D'Eau Claire r...@cobi.biz wrote: ABSOLUTELY! My HP mini-tower has what is called a whisper quiet fan and it is very quiet. It certainly does not interfere with conversation, even when carried on across our open office between desks ten feet apart. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] KPA 500 Fan Noise and cooling performance
I put a big fan (140x140mm) on top louvers for cooling, air injected into it, and temperature drops, sin is not available a quiet fan (like computers) ... maybe in the future ... rodolfo IK4VFD - Original Message - From: donehrl...@q.com To: elecraft@mailman.qth.net Sent: Monday, June 18, 2012 8:11 PM Subject: [Elecraft] KPA 500 Fan Noise and cooling performance On 6/18/2012 4:42 AM, David Robertson wrote: ( ... a long message I won't include here where he improved amplifier cooling by tightening heatsink/right panel screws and used heatsink compound.) I operate my KPA500 with the fan speed set to #1 continuously which delays the increase in the increase in fan speed once the amplifier starts putting out power. My amplifier did not exceed 58 deg C after 10 minutes at 500 watts carrier output into a dummy load and it stabilized at about 60 degrees in a 25 degree C room. My right panel to heatsink screws (the ones under the handle) were all tight and that explains why my experience was better than was Dave's originally before he tightened his heatsink screws and added heatsink compound. I then added heatsink compound to the mating surface between my heatsink and the right side panel. There was no difference in cooling performance at all. I just wanted to know .. and now I do .. and so do you. The KPA500 fan is as quiet as any muffin fan ought to be but it was still annoying to me. That is not an amplifier fault .. it is just that I have good hearing and I prefer a *very quiet shack. For those who may be like me in that regard here is how I reduced the normal fan noise of my amplifier. In my amplifier much of the fan noise was actually coming from the sheet metal of the amplifier structure which was being excited by the vibration of the fan which is rigidly attached to the amplifier structure so that fan vibration was communicated to the structure which then resonated and amplified the fan noise. When I removed the fan and held it loosely in my hand while it was running I could feel the light high frequency 'buzz' produced by the rotating magnetic field of the fan and also, crucially, the lower frequency throb caused by a slight weight imbalance in the rotor. I used a small piece of sticky pad (normally used to mount components to a chassis, etc) and placed this very small weight at various points on the rotor blades until, by trial and error, found the 'sweet' spot which resulted in greatly reduced throb. That reduced fan noise considerably. Then, to reduce transmission of fan vibration to the amplifier structure even further, I mounted the fan loosely to the back of the amplifier using soft quarter-inch cushions between the fan and the amplifier. I used light wire to do the actual attachment instead of the long screws that are standard. The overall effect is considerably less fan noise and I am very happy about that. The fan mounting is fragile and not to be recommended if the amplifier is to be moved very much but in my installation it is just fine. By the way, I carefully compared cooling performance before and after the fan mounting modification and found no difference at all. I also noticed during my testing that the direction of airflow makes no difference. Don K7FJ __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Nessun virus nel messaggio in arrivo. Controllato da AVG - www.avg.com Versione: 9.0.930 / Database dei virus: 2433.1.1/5079 - Data di rilascio: 06/19/12 08:49:00 __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] KPA 500 Fan Noise and cooling performance
Computers quiet? Obviously have not heard mine. I have tried to get after-market fans that were advertised as quiet, but no luck. Even some that others swore were much quieter. Apparently that which actually makes a fan quiet is not part of quality control. I've seen two fans of the same model number that simply don't look the same. Go figure. I've given up. Until I can go into a store and somehow listen to the exact one I'm buying, I don't believe any of the advertising. 73, Guy. On Tue, Jun 19, 2012 at 1:39 PM, rodolfo rodo...@tin.it wrote: I put a big fan (140x140mm) on top louvers for cooling, air injected into it, and temperature drops, sin is not available a quiet fan (like computers) ... maybe in the future ... rodolfo IK4VFD - Original Message - From: donehrl...@q.com To: elecraft@mailman.qth.net Sent: Monday, June 18, 2012 8:11 PM Subject: [Elecraft] KPA 500 Fan Noise and cooling performance On 6/18/2012 4:42 AM, David Robertson wrote: ( ... a long message I won't include here where he improved amplifier cooling by tightening heatsink/right panel screws and used heatsink compound.) I operate my KPA500 with the fan speed set to #1 continuously which delays the increase in the increase in fan speed once the amplifier starts putting out power. My amplifier did not exceed 58 deg C after 10 minutes at 500 watts carrier output into a dummy load and it stabilized at about 60 degrees in a 25 degree C room. My right panel to heatsink screws (the ones under the handle) were all tight and that explains why my experience was better than was Dave's originally before he tightened his heatsink screws and added heatsink compound. I then added heatsink compound to the mating surface between my heatsink and the right side panel. There was no difference in cooling performance at all. I just wanted to know .. and now I do .. and so do you. The KPA500 fan is as quiet as any muffin fan ought to be but it was still annoying to me. That is not an amplifier fault .. it is just that I have good hearing and I prefer a *very quiet shack. For those who may be like me in that regard here is how I reduced the normal fan noise of my amplifier. In my amplifier much of the fan noise was actually coming from the sheet metal of the amplifier structure which was being excited by the vibration of the fan which is rigidly attached to the amplifier structure so that fan vibration was communicated to the structure which then resonated and amplified the fan noise. When I removed the fan and held it loosely in my hand while it was running I could feel the light high frequency 'buzz' produced by the rotating magnetic field of the fan and also, crucially, the lower frequency throb caused by a slight weight imbalance in the rotor. I used a small piece of sticky pad (normally used to mount components to a chassis, etc) and placed this very small weight at various points on the rotor blades until, by trial and error, found the 'sweet' spot which resulted in greatly reduced throb. That reduced fan noise considerably. Then, to reduce transmission of fan vibration to the amplifier structure even further, I mounted the fan loosely to the back of the amplifier using soft quarter-inch cushions between the fan and the amplifier. I used light wire to do the actual attachment instead of the long screws that are standard. The overall effect is considerably less fan noise and I am very happy about that. The fan mounting is fragile and not to be recommended if the amplifier is to be moved very much but in my installation it is just fine. By the way, I carefully compared cooling performance before and after the fan mounting modification and found no difference at all. I also noticed during my testing that the direction of airflow makes no difference. Don K7FJ __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Nessun virus nel messaggio in arrivo. Controllato da AVG - www.avg.com Versione: 9.0.930 / Database dei virus: 2433.1.1/5079 - Data di rilascio: 06/19/12 08:49:00 __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html __ Elecraft mailing list Home: http://mailman.qth.net/mailman
Re: [Elecraft] KPA 500 Fan Noise and cooling performance
On Tue, Jun 19, 2012 at 1:26 PM, Guy Olinger K2AV olin...@bellsouth.netwrote: ...I have tried to get after-market fans that were advertised as quiet, but no luck... === Agreed. I recently built a tower computer and put in a neat-looking 18 cm. fan in the top of the case. Because it is so huge and runs at low RPM, it is a little quieter than my previous computer, and it does have the advantage of emitting an eerie red glow from its LED-illuminated clear plastic blades. However, it is just another failed experiment in my attempt to find a quiet fan. I read somewhere that Apple has a neat fan design in its newest machines. It is balanced but the blades are various different sizes, which apparently creates a spectrum of audio resonances instead of a single hum. However, I've never heard one in real life so I can't attest that it works. Tony KT0NY -- http://www.isb.edu/faculty/facultydir.aspx?ddlFaculty=352 __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] KPA 500 Fan Noise and cooling performance
Solution - the Dyson blade less fan. Hihi On Jun 19, 2012 1:41 PM, Tony Estep estept...@gmail.com wrote: On Tue, Jun 19, 2012 at 1:26 PM, Guy Olinger K2AV olin...@bellsouth.net wrote: ...I have tried to get after-market fans that were advertised as quiet, but no luck... === Agreed. I recently built a tower computer and put in a neat-looking 18 cm. fan in the top of the case. Because it is so huge and runs at low RPM, it is a little quieter than my previous computer, and it does have the advantage of emitting an eerie red glow from its LED-illuminated clear plastic blades. However, it is just another failed experiment in my attempt to find a quiet fan. I read somewhere that Apple has a neat fan design in its newest machines. It is balanced but the blades are various different sizes, which apparently creates a spectrum of audio resonances instead of a single hum. However, I've never heard one in real life so I can't attest that it works. Tony KT0NY -- http://www.isb.edu/faculty/facultydir.aspx?ddlFaculty=352 __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] KPA 500 Fan Noise and cooling performance
My solution was to buy a Mac Mini, which is as quiet as a church mouse. 73, Scott, N9AA On 6/19/12 2:43 PM, Gerald Manthey wrote: Solution - the Dyson blade less fan. Hihi __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] KPA 500 Fan Noise and cooling performance
Has anyone every operated one of those in close proximity to an HF rig? We built such fans in College way back in the 1950's and they were a bad of an RFI generator as any Tesla coil or Van De Graaf generator in the lab! After all, they work by electrostatic discharge. Ron AC7AC -Original Message- Solution - the Dyson blade less fan. Hihi On Jun 19, 2012 1:41 PM, Tony Estep estept...@gmail.com wrote: __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] KPA 500 Fan Noise and cooling performance
I could be wrong, but I think that the Dyson bladeless fan has, in its base, a regular ol' fan, with blades. As I understand it, that fan blows air out of holes in the trailing edge of the circular airfoil. Aerodynamic effects cause a larger volume of air to be dragged through the airfoil than the fan itself is pushing through the little holes. If that's so, it ought to be no worse a generator of RFI than any other fan. 73, Wayne Conrad KF7QGA On 06/19/12 12:24, Ron D'Eau Claire wrote: Has anyone every operated one of those in close proximity to an HF rig? We built such fans in College way back in the 1950's and they were a bad of an RFI generator as any Tesla coil or Van De Graaf generator in the lab! After all, they work by electrostatic discharge. Ron AC7AC -Original Message- Solution - the Dyson blade less fan. Hihi On Jun 19, 2012 1:41 PM, Tony Estepestept...@gmail.com wrote: __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] KPA 500 Fan Noise and cooling performance
On 6/19/2012 11:26 AM, Guy Olinger K2AV wrote: Computers quiet? Obviously have not heard mine. I have tried to get after-market fans that were advertised as quiet, but no luck. For a long time, I've been buying only top line Thinkpads (laptops), and they're pretty quiet. Back when I was buying tower computers for my office, I replaced the power supplies with Silencer models made by PC Power and Cooling. They're also very well built supplies. pcpower.com 73, Jim K9YC __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] KPA 500 Fan Noise and cooling performance
It would be interesting and perhaps not good in the shack if this were the case but these are not electrostatic. they are nothing more than a fancy venturi to amplify air flow Air enters the base of the unit through a “mixed flow impeller” a fancy name for a turbo like fan. and is forced out of a slot. The slot runs around the inside of the ring-shaped fan body, across a “aircraft wing shape” and then outward into the room. In short, it sucks air in through the base and blows it out of a very thin slot in the inside of the ring-shaped upper body drawing additional air though it. On 6/19/2012 3:24 PM, Ron D'Eau Claire wrote: Has anyone every operated one of those in close proximity to an HF rig? We built such fans in College way back in the 1950's and they were a bad of an RFI generator as any Tesla coil or Van De Graaf generator in the lab! After all, they work by electrostatic discharge. Ron AC7AC -Original Message- Solution - the Dyson blade less fan. Hihi On Jun 19, 2012 1:41 PM, Tony Estepestept...@gmail.com wrote: __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] KPA 500 Fan Noise and cooling performance
ABSOLUTELY! My HP mini-tower has what is called a whisper quiet fan and it is very quiet. It certainly does not interfere with conversation, even when carried on across our open office between desks ten feet apart. And yet, when I power down the machine at the end of the day, the sudden quiet is priceless. It's a sudden cessation of audio pressure removed the moment it stops. That background something one grows used to and learns to ignore, but it's neither desirable or pleasant. Like anything that increases stress, learning to ignore it does not mean it is no longer causing harm. 73, Ron AC7AC -Original Message- Computers quiet? Obviously have not heard mine. I have tried to get after-market fans that were advertised as quiet, but no luck. Even some that others swore were much quieter. Apparently that which actually makes a fan quiet is not part of quality control. I've seen two fans of the same model number that simply don't look the same. Go figure. I've given up. Until I can go into a store and somehow listen to the exact one I'm buying, I don't believe any of the advertising. 73, Guy. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
[Elecraft] KPA 500 Fan Noise and cooling performance
On 6/18/2012 4:42 AM, David Robertson wrote: ( ... a long message I won't include here where he improved amplifier cooling by tightening heatsink/right panel screws and used heatsink compound.) I operate my KPA500 with the fan speed set to #1 continuously which delays the increase in the increase in fan speed once the amplifier starts putting out power. My amplifier did not exceed 58 deg C after 10 minutes at 500 watts carrier output into a dummy load and it stabilized at about 60 degrees in a 25 degree C room. My right panel to heatsink screws (the ones under the handle) were all tight and that explains why my experience was better than was Dave's originally before he tightened his heatsink screws and added heatsink compound. I then added heatsink compound to the mating surface between my heatsink and the right side panel. There was no difference in cooling performance at all. I just wanted to know .. and now I do .. and so do you. The KPA500 fan is as quiet as any muffin fan ought to be but it was still annoying to me. That is not an amplifier fault .. it is just that I have good hearing and I prefer a *very quiet shack. For those who may be like me in that regard here is how I reduced the normal fan noise of my amplifier. In my amplifier much of the fan noise was actually coming from the sheet metal of the amplifier structure which was being excited by the vibration of the fan which is rigidly attached to the amplifier structure so that fan vibration was communicated to the structure which then resonated and amplified the fan noise. When I removed the fan and held it loosely in my hand while it was running I could feel the light high frequency 'buzz' produced by the rotating magnetic field of the fan and also, crucially, the lower frequency throb caused by a slight weight imbalance in the rotor. I used a small piece of sticky pad (normally used to mount components to a chassis, etc) and placed this very small weight at various points on the rotor blades until, by trial and error, found the 'sweet' spot which resulted in greatly reduced throb. That reduced fan noise considerably. Then, to reduce transmission of fan vibration to the amplifier structure even further, I mounted the fan loosely to the back of the amplifier using soft quarter-inch cushions between the fan and the amplifier. I used light wire to do the actual attachment instead of the long screws that are standard. The overall effect is considerably less fan noise and I am very happy about that. The fan mounting is fragile and not to be recommended if the amplifier is to be moved very much but in my installation it is just fine. By the way, I carefully compared cooling performance before and after the fan mounting modification and found no difference at all. I also noticed during my testing that the direction of airflow makes no difference. Don K7FJ __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
