Ed, I would also recommend doing the power calibration on 40 meters - it is a good compromise. There \is some variation in the response of the diodes with respect to frequency, and also, if you are using an oscilloscope to measure the RF voltage, the bandwidth of the 'scope can cause some "confusion" - if your 'scope (and probe) is rated at 35 MHz, the vertical response will be down 3 dB at 35 MHz. The use of a 'scope rated at 35 MHz can be used for RF voltage measurements at 7 MHz, but using it at 14 MHz, expect that the RF voltage shown by the scope will be less than the actual RF voltage. Do not even think of using a hunk of coax attached to the 'scope to measure RF voltages with any accuracy - a 10X probe is mandatory to keep the 'scope from loading the device to be measured (in this case, the transmitter output).
73, Don W3FPR On 8/13/2011 7:53 PM, EMD wrote: > Thanks Don, > > I will give that a try. Should I use the RF probe that I made or just use > the DMM probes? > > 73, > Ed ke7hga > > -- > View this message in context: > http://elecraft.365791.n2.nabble.com/KAT2-Bridge-null-adjustment-tp6683608p6684038.html > Sent from the Elecraft mailing list archive at Nabble.com. > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
