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Working with RF

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gamozo:
Greetings,

I've yet to really play around with some RF stuff, and I've just started to figure stuff out. I have a simple 555 timer (I know, it's crude) pumping out a 1060Hz signal, and a small little diode receiving the signal and then it is 'amplified' (still have slight issues there) by a single transistor. I've notice loads of issues when I try to probe the circuit. The second I connect up my scope, the signal is changed. Is there any good way to make probing a bit more practical? Also, what's a good way to amplify a signal coming from an antenna?

Thanks in advance

Psi:
Try x10 on the probe, or even x100 if you have it.

gamozo:
Yeh, I have 10x, I should get some new probes some day, but I might get a new scope. I'm correct when I think that having it on 10x greatly increases the resistance, thus much less disruption in the circuit?

Time:
1 kHz is not RF.  I have a hard time believing your probe would introduce any loading to your circuit.  Maybe I am missing something here.  Impedance is the word you want, not necessarily resistance.

Mechatrommer:

--- Quote from: Time on September 26, 2011, 07:40:25 pm ---1 kHz is not RF.
--- End quote ---
i was about to say this. but i dont think i'm the right guy to say it first.

--- Quote from: gamozo on September 26, 2011, 05:22:46 pm ---small little diode receiving the signal and then it is 'amplified' (still have slight issues there) by a single transistor. I've notice loads of issues when I try to probe the circuit. The second I connect up my scope, the signal is changed. Is there any good way to make probing a bit more practical? Also, what's a good way to amplify a signal coming from an antenna?

--- End quote ---
where do you probe? at the diode or at the transistor? since this is very small signal, probing at the diode may change the amplified signal dramatically, i suspect. can you change to an opamp instead of the transistor to amplify the signal and probe at the opamp output? or what about the normal LC tank as receiver? sorry i'm no expert, cannot give you precise answer.

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