DragonMaster said:
Logic analyzers, unless they are very fancy/expensive, are good when everything is clocking right. Sometimes you need a scope so you can find clock problems that you can't find with a logic analyzer. When your logic analyzer gives you garbage but the simulator tells you it should all be working, its time to break out the o-scope and start looking for glitches that shouldn't be there.
Always get as much BW as you can afford, and get probes to match. If the probe BW isn't at least as high as the scope, you're wasting capability of the scope.
I_F
actually you don't need a wideband probe or scope to align fm receivers. you use a frequency modulated rf generator and an rf "sniffer" probe which consists of a pair of low capacitance diodes, a resistor and a couple of 100pf caps in a voltage multiplier arrangement. the output of the probe goes to the scope vertical, and the modulating voltage (sine wave or triangle wave) goes to the rf generator and the scope horizontal input with the scope in "XY" mode. the rf generator should be set up to provide about 200khz deviation. with the probe at the mixer input, you align the rf stages, and with the probe at the detector input you align the if stages. the scope gives you a response curve with the center frequency in the middle, and +/-100 khz at the edges.
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