Larry, I wasn't aware of a menu entry limiting power. I have seen and used "Hi Cur" for current monitoring/limiting. Can you tell me where the power limiter (and what version of firmware you see it on, perhaps I am using an earlier version.
Thanks Tom, WB2QDG k2 1103 "Today's problems are caused by yesterday's solutions" -----Original Message----- From: W3FPR - Don Wilhelm <[EMAIL PROTECTED]> To: Larry Dodson <[EMAIL PROTECTED]>; Elecraft reflector <[email protected]> Date: Sunday, September 19, 2004 9:27 AM Subject: Re: [Elecraft] Low Power ? Larry, The K2 is speced for 10 watts out on all bands with a 13.8 volt power supply, and most are capable of about 12 watts on the higher bands (10/12 meters) and 15 watts on 17 meters and below. Recall that there is a menu entry (secondary menu) that sets the power limit on 10 meters - it defaults to 10 watts. If you are checking for maximum power on that band, you may want to temporarily set that value to 15 watts. You could first try repeaking the bandpass filters - the K2 typically has more gain on 40 and 30 meters, so your low 40 meter output gives me suspicion. The most common reason for low power output is T2. T2 should be wound so that the secondary (green wire) is spread over most of the primary turns, and it should be mounted above the board by about 1/16 inch (2mm). You may want to download the latest manual and look at the illustration for T2. Also check T4 - make certain it has the proper number of turns and that it was not wound for maximum efficiency at 5 watts. Last but not least, be certain your wattmeter is correct - many are not, and be certain your dummy load is actually 50 ohms resistive on the band you are investigating. If you have a calibrated 'scope with a frequency limit of 50 MHz or more, you can check the wattmeter by observing the RF voltage across the dummy load. Power can be calculated as the square of the Peak to Peak Voltage divided by 400 for a 50 ohm load (yes, you can do all the peak to RMS conversions and arrive at the same thing - I will leave the proof to the 'student'). An RF probe can also be used to measure the RF voltage, and in that case the probe shows RMS voltage and the power is calculated as V**2/R. 73, Don W3FPR ----- Original Message ----- I wonder if my K2 (Serial # 2424 with latest mods and software) is set up correctly and would appreciate comments. Output power with CAL CURR set at 3.0 amps is as below. Increasing CAL CURR to 5 amps makes little difference. I know that the K2 is basically a 10 watt rig and I get more on some bands, but the upper bands do not achieve this. When using the K2 with my KW1000 Linear Amplifier a watt or two makes a difference. 80 Meters = 13.0 watts out 40 Meters = 10.0 watts out 30 Meters = 12.0 watts out 20 Meters = 11.0 watts out 15 Meters = 8.0 watts out 12 Meters = 9.5 watts out 10 Meters = 7.0 watts out _______________________________________________ Elecraft mailing list Post to: [email protected] 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: [email protected] 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
