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  #1  
Old 01-02-2021, 10:03 PM
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Kevin Kuehn Kevin Kuehn is offline
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Hey you did good. Seems to be working really well, and it's quite sensitive. That will be very interesting once you get outdoors away from all the modern rf noise sources. If you have a scope with a DC coupling you can monitor the AVC voltage line and watch the trace move up and down as you change the tuning.
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Old 01-03-2021, 08:15 PM
vortalexfan vortalexfan is offline
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Originally Posted by Kevin Kuehn View Post
Hey you did good. Seems to be working really well, and it's quite sensitive. That will be very interesting once you get outdoors away from all the modern rf noise sources. If you have a scope with a DC coupling you can monitor the AVC voltage line and watch the trace move up and down as you change the tuning.
Yes I do have an oscilloscope, and I think it does have DC Coupling but I'm not sure, the 'scope I have is a Tektronix Model 453 that is a Hybrid (part solid state part Nuvistor Tube powered).

How do I know if the 'scope I have has DC Coupling?
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Old 01-03-2021, 08:18 PM
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Originally Posted by vortalexfan View Post
Yes I do have an oscilloscope, and I think it does have DC Coupling but I'm not sure, the 'scope I have is a Tektronix Model 453 that is a Hybrid (part solid state part Nuvistor Tube powered).

How do I know if the 'scope I have has DC Coupling?
You don't need a scope for this - a DC voltmeter will work.
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Old 01-03-2021, 08:44 PM
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Tis true but it's more fun watching the scope trace in a dimly lite room. Plus it's a great way to get comfortable working all those intimidating controls. Most modern scopes have a AC-DC coupling switch near each channel input.
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Old 01-03-2021, 09:26 PM
vortalexfan vortalexfan is offline
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Originally Posted by Kevin Kuehn View Post
Tis true but it's more fun watching the scope trace in a dimly lite room. Plus it's a great way to get comfortable working all those intimidating controls. Most modern scopes have a AC-DC coupling switch near each channel input.
Yes, I just looked at the front panel on mine and it does have a switch for selecting different coupling options including DC.

My Oscilloscope has 3 different probes 2 of them say 10x 100MHz 13pF 10MΩ 2 meter, and the 3rd one says 10x 10pF 10MΩ 2 meter, does anyone know what that's referring to?

See picture below.
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File Type: jpg Tektronix Oscilloscope.jpg (51.6 KB, 8 views)
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Old 01-03-2021, 10:19 PM
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Kevin Kuehn Kevin Kuehn is offline
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My Oscilloscope has 3 different probes 2 of them say 10x 100MHz 13pF 10MΩ 2 meter, and the 3rd one says 10x 10pF 10MΩ 2 meter, does anyone know what that's referring to?
10x means it's a divide by 10 probe. So if you're measuring 10v it will look like 1v per division on the screen. Some scopes have both 1x and 10x positions marked on the volts per division selector. 10X also loads the measured signal less than 1X. The 13 and 10pf are the probes internal capacitance. Those aren't too critical until you're looking at square wave shapes. There's generally a capacitance matching trimmer for each channel input. You may have a calibration square wave terminal on the front panel you can connect the probe to and then you adjust the capacitance trimmer for that channel so the waveshape has square edges. 10M is the probes impedance.

[edit] Actually it's more likely the input capacitance trimmer is in the probe housing. You do have a 1kh calibration signal on the front panel left side.

Last edited by Kevin Kuehn; 01-03-2021 at 10:48 PM. Reason: Added info
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Old 01-03-2021, 11:12 PM
vortalexfan vortalexfan is offline
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Originally Posted by Kevin Kuehn View Post
10x means it's a divide by 10 probe. So if you're measuring 10v it will look like 1v per division on the screen. Some scopes have both 1x and 10x positions marked on the volts per division selector. 10X also loads the measured signal less than 1X. The 13 and 10pf are the probes internal capacitance. Those aren't too critical until you're looking at square wave shapes. There's generally a capacitance matching trimmer for each channel input. You may have a calibration square wave terminal on the front panel you can connect the probe to and then you adjust the capacitance trimmer for that channel so the waveshape has square edges. 10M is the probes impedance.

[edit] Actually it's more likely the input capacitance trimmer is in the probe housing. You do have a 1kh calibration signal on the front panel left side.
Can this 'scope be used to calibrate a signal generator, or a frequency counter?
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