Alan, while I do not own a W2 it would seem that the pickup coils in the sensor could be reduced in turns by the correct amount to lower the coupling loss loss by 3 dB. Would not the rest of the W2 work correctly at the 3 dB (or whatever you choose) lower power level?
Michael Blake - K9JRI > On Nov 20, 2015, at 12:07 PM, Alan <[email protected]> wrote: > > I just tested it. The maximum you can set the W2 calibration value to is > 650. (Using the ">" and "+" RS-232 commands) That causes the wattmeter to > read about 60% high on my W2. So with the W2 set to read 2000W full scale, > the actual full scale would be about 1250W. > > Or you could go in the other direction. The minimum calibration value is > 350, which causes the power to read about 47% (on my unit). With the W2 set > to read 200W full scale it would actually be about 425W full scale. > > Alan N1AL > > > On 11/20/2015 07:15 AM, Cliff Frescura wrote: >> I find the scaling awkward as well. My W2 is placed on the input side of my >> KPA500 and it seems that dividing the scale by two might do the trick. I've >> not looked at the schematic, but wonder if it could be tricked by a resistor >> divider in the sensor line. >> >> 73, >> >> Cliff K3LL >> >> -----Original Message----- >> From: Elecraft [mailto:[email protected]] On Behalf Of Don >> Wilhelm >> Sent: Friday, November 20, 2015 5:55 AM >> To: Scott Townley; [email protected] >> Subject: Re: [Elecraft] Rescaling the W2? >> >> Scott, >> >> I believe that would require a new sensor and firmware to support it. >> Popular scales on wattmeters are 200 watts and 2000 watts full scale, so you >> are not going to get much better with another brand product. >> The W2 used with its utility program can give you more resolution, but then >> using the Utility when mobile would not be advisable. >> >> 73, >> Don W3FPR >> >> On 11/20/2015 8:32 AM, Scott Townley wrote: >>> I know the W2 can be "dialed in" to match one's personal standard, >>> but...can it be completely rescaled? >>> I use the K3/KPA500/W2 mobile, and the KPA500 is mounted in my pickup >>> bed so the W2 is the only system meter available at the operating >>> position. However, the 2's scaling doesn't give me much display >>> dynamic range...the KPA500 will only light 5 of the 17 LEDs at full >>> power. >>> It would be far more useful for me to have the meter scaled to 600W >>> say...then the 15th LED would be 450W. Even scaling it to 1000W would >>> give me more than half the display range. >>> >>> >> >> ______________________________________________________________ >> 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] >> > ______________________________________________________________ > 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]
