Re: [Elecraft] PROs/CONs on KPA100
On Jan 21, 2007, at 3:18 PM, Darrell Snedecor wrote: If you have the KPA100 option installed I would be interested in hearing your take on it. I'm mainly interested in the things that you found out (good and otherwise) after you installed it as opposed to what you considered before buying it. I have the KPA100. I was surprised at how easy it was to build. It went together relatively quickly, and it worked the first time. I've run the KPA100 really hard for SSB and CW contests at 100 watts. It gets quite warm, but works effectively. On 160m, it tends to draw a bit too much current from my power supply, so I'll back down to 85-90 watts. One disappointment is that the KPA100 isn't designed for 100% duty cycle. On RTTY contests, I can only run 20-30 watts without overheating the PA. I've added a supplemental cooling fan that sits on top of the KPA100 right between the transistors. With this, I can run 50 watts without problems. Bill Coleman, AA4LR, PP-ASELMail: [EMAIL PROTECTED] Quote: Not within a thousand years will man ever fly! -- Wilbur Wright, 1901 ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
RE: [Elecraft] PROs/CONs on KPA100
I don't think this is true. Before the KPA100, my K2 had no fan. Front panel control board ran with no cooling support and drift was never an issue. I run the KPA100 with an external fan which keeps the hovercraft wizzer on the back of the rig from coming to life. Again, the front panel and control board operate with no cooling. - Keith N1AS - - K2 5411.ssb.100 - -Original Message- From: Darrell Bellerive From what I understand, one of the reasons for the fan is to keep the K2 RF, front panel, and control board components at a fairly constant temperature to reduce drift, etc. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] PROs/CONs on KPA100
There is a fan accessory from Ten Tec for the Orion that is mounted on a metal bracket. It fits very nicely onto the KPA100 heatsink and is pretty quiet. You can even put a resistor in the line and drop the voltage from 12V to 5-7 V to cut down the RPM and make it almost dead quiet while still providing additional cooling at the heatsink. Lets go even better for those who like to experimentYou can put together a simple but effective water cooling system such as what is used for computer CPUs. Cut away the fins on the heatsink above where the finals are and mount a waterblock to the heatsink above the finals. This will draw the heat to the liquid that goes to a small radiator for cooling. A small pump keeps the system circulating. This should keep the small fan from having to come on at all. While this is a spur of the moment idea.it seems like it should workand well enough that you should be able to run digital modes without reduced power. Has anyone tried something like this? GL Greg AB7R On Tue, 23 Jan 2007 12:01:04 -0500 Darwin, Keith [EMAIL PROTECTED] wrote: I don't think this is true. Before the KPA100, my K2 had no fan. Front panel control board ran with no cooling support and drift was never an issue. I run the KPA100 with an external fan which keeps the hovercraft wizzer on the back of the rig from coming to life. Again, the front panel and control board operate with no cooling. - Keith N1AS - - K2 5411.ssb.100 - -Original Message- From: Darrell Bellerive From what I understand, one of the reasons for the fan is to keep the K2 RF, front panel, and control board components at a fairly constant temperature to reduce drift, etc. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] PROs/CONs on KPA100
Amateur astronomers use Peltier devices to cool the CCD on their astrocameras. The Peltier unit cools and circulating water/alcohol removes the heat. Without cutting a fin, aquarium tubing could be woven through the fins circulating cool liquid via a small pump system. These systems are small and are DIY. Then there is always liquid nitrogen. g 73 Gil NN4CW K2#3104 ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] PROs/CONs on KPA100
Then there is always liquid nitrogen. g Better check the temp specs on the finals -- might be TOO cold. Mark On 1/23/07, Gil Stacy [EMAIL PROTECTED] wrote: Amateur astronomers use Peltier devices to cool the CCD on their astrocameras. The Peltier unit cools and circulating water/alcohol removes the heat. Without cutting a fin, aquarium tubing could be woven through the fins circulating cool liquid via a small pump system. These systems are small and are DIY. Then there is always liquid nitrogen. g 73 Gil NN4CW K2#3104 ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] PROs/CONs on KPA100
G'day, Biggest con: the fan. I find it loud and distracting, and even after the KPA100 cools down to threshold temperature, the fan remains on until an event such as transmittion of CW sig. This means if the fan kicks in during high power transmit, then you go back into receive mode to listen to the other station for a while, fan remains on (loudly) forever, and I deliberately have to send a CW dit to force it to (re-evaluate temp?) and turn itself off. This potentially confuses the op on the other end who thinks I'm trying to get his attention. If it doesnt' really work that way, please correct me, but that's been my experience. Not how mine works, or as it is intended to work. This doesn't fit in with any fan mode offered in the menu. Noisy, yes, distracting, yes, however, when the heatsink cools to the threshold temp mine shuts off as described in the manual. External fans have been discussed at length for extended operation with the upside that the noisy little - your word(s) - doesn't even come on. Regards, Mike VP8NO ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] PROs/CONs on KPA100
Mike VP8NO wrote: Noisy, yes, distracting, yes, however, when the heatsink cools to the threshold temp mine shuts off as described in the manual. External fans have been discussed at length for extended operation with the upside that the noisy little - your word(s) - doesn't even come on. Is it possible that some are noisy little err things and some are not? I have mine running all the time at LO (very quiet) when my KPA100 is on, and so far it has not switched itself to HI (noisy) even during a contest. Shack ambient temperature is usually about 65 F. The heatsink gets warm but not hot. 73, Geoff GM4ESD ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
RE: [Elecraft] PROs/CONs on KPA100
I built mine in early Dec 06. Worked fine the first time. I love the way it integrates with the rig and it works just fine. The only disappointment is the fan. As others have said, it is noisy. I have a muffin fan that I set on top of the heat sink to keep the built-in whizzer fan from coming on. It works but it too generates a bit of low-level noise in the shack. Knowing what I now know, yes, I'd buy it again. CW at 12 watts is fun but sometimes that extra 80 watts makes the difference. - Keith N1AS - - K2 5411.ssb.100 - -Original Message- If you have the KPA100 option installed I would be interested in hearing your take on it. I'm mainly interested in the things that you found out (good and otherwise) after you installed it as opposed to what you considered before buying it. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] PROs/CONs on KPA100
On January 22, 2007 12:29 pm, Darwin, Keith wrote: The only disappointment is the fan. As others have said, it is noisy. From what I understand, one of the reasons for the fan is to keep the K2 RF, front panel, and control board components at a fairly constant temperature to reduce drift, etc. If the KPA100 is mounted in a separate EC2 cabinet, would the need for a fan be eliminated? What about if the KPA100 shares an EC2 with a KAT100? Or could a larger heat sink be substituted? -- Darrell Bellerive Amateur Radio Stations VA7TO and VE7CLA Grand Forks, British Columbia, Canada ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
RE: [Elecraft] PROs/CONs on KPA100
Built my KPA100 in 2002 and it's FB. Delivers 100 on 160 through 10 meters. It worked exactly as advertised and I expected. I chose the Elecraft K2 for fixed-station use so my KPA100 is built into the K2 as it was originally designed. Like the K2 itself it's had lots of heavy use with no problems. It went together easily and worked first time power was applied. Over the years I've kept mine current with the latest Elecraft updates even though it had no performance issues from the beginning. Ron AC7AC If you have the KPA100 option installed I would be interested in hearing your take on it. I'm mainly interested in the things that you found out (good and otherwise) after you installed it as opposed to what you considered before buying it. Best regards, Darrell (Formerly KB9AV and working to get it back!) ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] PROs/CONs on KPA100
If you have the KPA100 option installed I would be interested in hearing your take on it. I'm mainly interested in the things that you found out (good and otherwise) after you installed it as opposed to what you considered before buying it. Biggest pro: the entire section remains disabled (no current drain) until required by dialing up the power potentiometer. Your QRP K2 stays just that until you choose to go over 12-ish watts. Biggest con: the fan. I find it loud and distracting, and even after the KPA100 cools down to threshold temperature, the fan remains on until an event such as transmittion of CW sig. This means if the fan kicks in during high power transmit, then you go back into receive mode to listen to the other station for a while, fan remains on (loudly) forever, and I deliberately have to send a CW dit to force it to (re-evaluate temp?) and turn itself off. This potentially confuses the op on the other end who thinks I'm trying to get his attention. If it doesnt' really work that way, please correct me, but that's been my experience. That said, it's a great module. There when I need it, disabled when I don't. I sold mine very recently after MUCH deliberation. Sad to see it go but I'm doing more QRP nowadays and trying to pare down. nv1b ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
