Hi Alan, That's good news! Glad you went for a walk and had a revelation, I think I need a little longer walk perhaps! I'm still having problems but gathering good data for help I hope. I have enabled my modules and filters but still no received broadcast, WWV time signal or Ham traffic. Hence I have not done the Reference Oscillator Calibration and not able to do the Wattmeter adjustment although I do get a 14.050 Mhz 15mv RF signal (and a 7.050 Mhz signal at 60mv-only a 20 Mhz 'scope) at the proper respective frequencies when TUNE is pressed but VFO A has no effect on the output signal according to the oscilloscope. Am emailing [email protected] and hope they find, as you say, that they can cure my 'Stupid' :-)
I'm confused as to getting these messages on the Elecraft Reflector, I hope this one makes it. 73, Tom NB5Q On Sat, Dec 16, 2017 at 6:56 PM, Don Wilhelm <[email protected]> wrote: > Tom, > > The K3 wattmeter calibration is different than the K3 Utility TX gain > calibration. > > Do the wattmeter calibration as indicated in the manual, and then you can > do the TX Gain calibration from K3 Utility. > > 73, > Don W3FPR > > On 12/16/2017 8:33 PM, Tom Norris wrote: > >> OK on the scope frequency response, I will use that info when I look at >> that tomorrow (too late now, in the house with XYL) Just C >> urious >> >> if the K3 Utility Transmitter Gain >> Calibration >> (pg >> 52) >> rel >> ies >> on the K3 power >> watt >> meter reading responding correctly (after manual Wattmeter >> calibration on pg 52). Could this explain the failure of the K3 Utility >> Transmitter Gain Calibration try earlier. >> >> Thanks, Tom NB5Q >> >> On Dec 16, 2017 5:55 PM, "Don Wilhelm" <[email protected] <mailto: >> [email protected]>> wrote: >> >> Tom, >> >> If your 'scope is rated at 20 MHz, that is the 3dB point for the >> vertical amplifier. It will show only 1/2 of the actual amplitude >> at 20 MHz. Use a frequency that is 1/3 or less of the 'scope >> rating to get an accurate vertical voltage response - i.e. use 7 >> MHz or below. >> >> I trust a 100MHz scope only to 30MHz for correct vertical >> amplitude, and the 10X probes must be rated for 100 MHz and above >> for that situation to be accurate. A 1X probe or a piece of coax >> used as a probe may not produce an accurate indication of the RF >> voltage. >> >> 73, >> Don W3FPR >> >> On 12/16/2017 7:38 PM, Tom Norris wrote: >> >> Thanks Don, I will look at the signal with a 20 Mhz scope and >> see what the voltage is during xmt. Since I did not see any >> K3S display change while making adjustment with VFO A knob or >> hear any signal increase in the Omni D I was thinking I'm not >> affecting the power adjustment of the K3S. >> Thanks, Tom NB5Q >> >> On Dec 16, 2017 5:29 PM, "Don Wilhelm" <[email protected] >> <mailto:[email protected]> <mailto:[email protected] >> >> <mailto:[email protected]>>> wrote: >> >> Tom, >> >> Have you checked that external wattmeter at 5 watts? >> Many wattmeters when on the 200 watt range may not show any >> significant output until you get to 10 or 20 watts. >> >> Use the 20 watt range on the wattmeter - and do not really >> trust >> it at the 5 watt level. The diodes in many wattmeters are a >> potential problem and may not register anything unless the >> power >> is 10 watts and above. The exception is QRP wattmeters with op >> amps and compensating diodes. >> >> If you have access to a 'scope with a 10X probe, that is more >> accurate. >> Set the scope to read the RF voltage and connect it across the >> dummy load. If your dummy load does not allow access to >> the coax >> center conductor, use a Tee adapter to access the center >> conductor. >> The RF peak to peak voltage for 5 watts is 44.7 volts. >> >> Bottom line - do not trust your instruments (wattmeter in this >> case) until it is proven trustworthy at the power level >> involved. >> >> 73, >> Don W3FPR >> >> >> On 12/16/2017 6:20 PM, Tom Norris wrote: >> >> Newly assembled working great so far. >> At the Owners Manual Calibration Procedures pg 52 >> (Fred Cady >> book Elecraft >> K3S and P3 referred me to Owners Manual for some >> Calibrations >> after going >> through Configuring the K3S pg 26...) >> Wattmeter: >> Both CONFIG:TUN PWR and PWR SET to NOR (KPA3A not >> installed >> yet, all covers >> on. >> Low-Power (5 W) W mtr calibration >> On 20 meter band at 14.050 >> On a 1kw Cantenna 50 ohm dummy load (ch'd w/ Ohm meter) >> Set power to 5.0 watts on K3S with Pwr knob >> Go to CONFIG WMTR LP showing >> Press TUNE (hear signal on Omni D) but does not >> register on >> ext W Mtr and >> cannot vary output with VFO A knob (which is the >> instructed >> 'Parameter' >> adjustment knob I assume?) >> Ext W Mtr is working ok with Omni D output >> >> >> >> > ______________________________________________________________ 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]
