How about 80 watts instead. Won't make a noticeable difference on the receive end.
Even better, get rid of all the Yaesu and Icom "Clackers" with their VERY poor CW performance. You can have the best class A amplifier in the world, but garbage in will always equal garbage out. I am ashamed at our "leaders" at the ARRL for not petitioning the FCC for better specs. The technology is there, they all use it in their business radios that have a better spec. Oh, I forgot, follow the money and take the advertising monies from these clackers Jim W6AIM -----Original Message----- From: Elecraft [mailto:[email protected]] On Behalf Of Don Wilhelm Sent: Thursday, October 29, 2015 7:41 AM To: frank; [email protected] Subject: Re: [Elecraft] IMD and supply voltage Frank, I think the "issue" is one of some hams wanting to make what is good already into something better. If you look closely you should discover that this is a situation common to *all* 100 watt class amplifiers that are supposed to run on a nominal '12 volt' supply. That voltage level is chosen because it is common for vehicle batteries, so most transceivers are designed around that voltage - the K3S is just one of those. Using an increased voltage power supply will drastically reduce the transmit IMD, and that is true for all those 100 watt class amplifiers. Bottom line is that I don't think it will be "fixed" in the K3S - I don't think it can be fixed in any of the 100 watt class solid state amplifiers. So the thing to do is to run the power supply voltage up to near 15 volts (but not above), and do not operate with "all knobs to the right". Many hams seen to want to squeeze all the power output that they can from a transceiver, so you will put a cleaner signal on the air if you set the power to 100 watts rather than trying to squeeze that last 20 extra watts out of an amplifier. 73, Don W3FPR On 10/29/2015 11:09 AM, frank wrote: > This subject keeps cropping up. Is this a serious issue ? > > I have heard that IMD improves by 10db with a one volt increase in supply voltage. Is this really the case or just a measurement error? 10db is a large difference. One volt is a small variation. > > What is the minimum acceptable IMD? How linear does the amp need to be? If 36db is better than 26db is 100db even better or just overkill? > > Are other solid state amplifier products similarly effected? > > What is the IMD performance of the K3S at 10 watts over a supply voltage variation from 11 volts to 14.7 volts? I ask because I believe those ten watts are generated by Dmos devices as well. Do these devices only misbehave with varying supply voltage at higher (100w) power levels and lower supply voltages? > > Should I wait to purchase a K3S until this issue is resolved? (Assuming this is a valid issue) > > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
