Re: Tracing receive signal for low signal
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Oscilloscope probes may have high impedance ..try measureing the dc resistance of the probes ..in both x1 and x10 positions ..really best to 'somehow' try to match the output impedance of the rf generator to the input impedance of the circuit under test
use a dc blocking capicitor (.01 uF is fine) between the rf generator and the circuit under test ..You will need to tune the rf gen for max output thru the filter ..may not be exactly 11.997 or whatever mhz ...depends on the crystals and the caps in the filter
On Friday, January 11, 2019, 5:56:14 PM PST, Dave Space <davesspacebar@...> wrote:
Hmm..I am rather new to this... I'm using the oscilloscope probes for both the signal generator input (set to 1x) at tp17 and oscilloscope probe at tp20 also set to 1x (as I believe I should be able to see the ~1khz or so signal at that point right? In the MHZ range I'd have to have it switched to 10x but figured I'm looking for low frequency 1x gives more granular voltage down to 2mv) I tried using a small cap but I think it offset the voltage... might have to try it again with that ac coupled maybe.
On Fri, Jan 11, 2019 at 05:37 PM, Bob Lunsford wrote:
The type tip/cable you use on the tp may also be a factor.