Gordon Gibby <ggibby@...>
Oh what fun!
Yesterday I built a simple capacitively coupled "probe" to be used with my (1st ever!) spectrum analyzer. A series cap of 0.01/1kV, 4700 ohm resistor, and 100 ohm to ground, (should have used 50 but didn't have it) -- then coax cable to the spectrum analyzer.
Gives roughly 15 dB attenuation based on touching the tracking generator signal.
Allows me to actually SEE the oscillators and signals as I roam around the uBix. Wow, the signals are TINY all around the receiver, and most of the gain must be in the audio section....
I built this for 2 reasons: primarilly so I can do this demo for our upcoming Extra Class course, and let people SEE mixers in action and oscillators and filters. Sending in a 100kHz calibrator (harmonics every 100 kHz) shows ALL the signals heading into
the 45 MHz filter --- and then poof, only 1 left afterwards!
2nd, I have a heathkit SB-102 with local oscillator problems and this will help.
Gordon Gibby KX4Z