I'm new to this forum so hi all! Someone recommended me this place to ask about oscilloscopes and electronic stuff.
I got this old Hitachi V-151B 15Mhz, 1 channel analog oscilloscope for learning purposes and to use it on my old 8-bit computer collection.
I know very basic electronics, I've made some circuits before, I've repaired some stuff, etc.
After playing for a couple of days with the scope I was able to learn how to use it, how to calibrate and what most of the knobs do.
It came with a user manual and a probe.
After reading it, I was able to make a couple of adjustments internally, for example, it wasn't displaying the voltage correctly, on the .5 calibration point it was displaying about 4.6v. After following the adjustment procedure in the manual it nows displays the voltage right. I've tested some batteries and it's working fine.
Now the thing is that I have 2 more adjustments that I can't make, the manual doesn't say anything about these adjustments.
1-Probe compensation.
2- Frequency/period not displaying right.
For the probe compensation I've tried the little trimmer in the probe, but I'm not able to make the flat part of the square totally flat, there's always over or under compensation, I've made a video showing this.
For the frequency/period problem, for example, when I try the 0.5v 1khz calibration signal, if I made the calculation it gives me 1111 Hertz.
I've also tried a phone app with a signal generator set to 1khz but the reading/calculation gives me the same thing.
Now, I'm not sure how accurate this oscilloscope is, but I think that's too much inacuracy right?
Also I'm not sure how reliable these signal generator app really is, but the calibration point on the scope isn't accurate then?
I'm sure that adjusting some of the internal pots I'll be able to calibrate it better, but I'm not sure what to touch. (I'm aware of the high voltages inside)
Any guidance will be very appreciated!!