I recently purchased a BK Precision 2120 and some new probs, im trying to calibrate the probes but i dont appear to be getting the 0.2V square wave no matter what settings i select. Is there anything else i can use to test to see if it is functioning? I have hooked it to a 12v PS and it appears to work with it jumping about 2.5 divisions then back down to zero again, ive also hooked it to a music signal and jumps around as i expect it would, does that mean that my 0.2v P-P just deosnt operate or does it mean something more serious?
COnnect your test point to the input of an amp. If the test signal is present it will come out the amplifier speaker.
Hook a test wire to the .2v terminal and touch the other end of the wire to the center pin of the probe jack - no probe connected for this. That eliminates the probe itself if the problem remains.
If you touch the probe to a DC voltage, and the trace jumps up then settles back down to zero, that is a sign of a series cap, which is what make AC coupling. If you set the vertical for DC coupling and a couple volts per division, and touch the probe to the terminals of a 9v battery, the trace should move a couple divisions and stay there.
Hook a test wire to the .2v terminal and touch the other end of the wire to the center pin of the probe jack - no probe connected for this. That eliminates the probe itself if the problem remains.
If you touch the probe to a DC voltage, and the trace jumps up then settles back down to zero, that is a sign of a series cap, which is what make AC coupling. If you set the vertical for DC coupling and a couple volts per division, and touch the probe to the terminals of a 9v battery, the trace should move a couple divisions and stay there.
Havent tried the amp yet.
used a wire from .2V to center of probe jack, after a few turns of the dial i get 2 lines of dashes but cant bring the speed down to make much out of it, it could be a square wave but no vertical lines connecting them together.
If i touch probe to 12 volts DC the display jumps about 2 1/2 division and stays there as long as i hold it
Also the Auto trigger was set without my knowledge but it didnt change much.
used a wire from .2V to center of probe jack, after a few turns of the dial i get 2 lines of dashes but cant bring the speed down to make much out of it, it could be a square wave but no vertical lines connecting them together.
If i touch probe to 12 volts DC the display jumps about 2 1/2 division and stays there as long as i hold it
Also the Auto trigger was set without my knowledge but it didnt change much.
ON a clean square wave, a lot of scopes don;t show much vertical line.
Your sweep trigger can probably be set to channel 1 or channel 2 or AC line freq. Make sure it is set to the channel you are using to see the square wave, otherwise the sweep won't sync and the waveform display will race along horizontally.
Set your horizontal sweep to 1msec/div/ That should put a 1kHz square wave at one cycle per division. Then turn the sync level control back and forth to see if a stable setting appears.
Is your probe set to X1 or X10? X10 shrinks the vertical by a factor of 10. If 12v moves 2-1/2 divisions, at the same settings, think how tiny would be a .2v signal. I get about 0.04 division. 12v is 60 times the size of 0.2v. Turn up the vertical on the channel.
Your sweep trigger can probably be set to channel 1 or channel 2 or AC line freq. Make sure it is set to the channel you are using to see the square wave, otherwise the sweep won't sync and the waveform display will race along horizontally.
Set your horizontal sweep to 1msec/div/ That should put a 1kHz square wave at one cycle per division. Then turn the sync level control back and forth to see if a stable setting appears.
Is your probe set to X1 or X10? X10 shrinks the vertical by a factor of 10. If 12v moves 2-1/2 divisions, at the same settings, think how tiny would be a .2v signal. I get about 0.04 division. 12v is 60 times the size of 0.2v. Turn up the vertical on the channel.
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