OT/gloat: I got an oscilloscope!

That's great. You will be able to do a million of new things with an oscilloscope.

Does your scope have a "beam find" button? Try pressing it.

also, try rotating the right to left indicator marked as

Hook up your probe to Ch1. Adjust the voltage(upper left knob, with red center) to appropriate division(200mv or 1V). Touch the probe to one of the metal terminals(dont' worry about the GND clip). You will need to adjust the time divisions to something appropriate. I would assume that the test terminals are going to generate a 1khz squarewave(just my experience). If that is the case, an appropriate time division would be 1ms.

Based on the previous, this should yield you a nice squarewave displayed on the screen. If you don't see anything, play with the offset knob(little knob to the left of voltage div knob). The offset may be set such that the signal is shifted off the screen.

Repeat for ch2.

Enough to get you started at least.

JW

Try:

how to use an oscilloscope

for your search term.

No, but you can burn the screen. Best bet really would be to find a copy of The Art of Electronics - still in print, best textbook I've ever had.

In "single shot" mode, that the thing has triggered, and will need to be reset. Not a very useful mode without a scope camera or digitizer; you want one of the modes that keeps retriggering (try "auto", for starters _ I can't read the controls on your photo, and don't have the same model, but it sounds like you are in single-shot mode, since you see one blip).

Handy for checking operation, actually. Clip the probe tip to one of them and see if your can get it to show a square wave (which is what should be coming off those points) of the appropriate magnitude.

And, you probably won't. They tricked the scope in some manner to get that picture. It is a 2-channel scope, so you mostly should only get 2 lines. Start simple. Set it for chan A only, and display to A sweep only, and sweep mode to auto. You should get one horizontal line. Connect a probe from the A input to one of the little metal rings under the Time/Div knob. Those are the calibrator outputs. By setting the right Volts/Div and Time/Div you should get either 2 horizontal lines or a square wave. The right settings of the trig source and

That indicates that the A or B sweep has found something to trigger on.

Those are the calibrator outputs. You have a choice of a 200 mV and a 1 V peak-to-peak square wave, usually at ~1 KHz. These are used to check the calibration of the vertical amplifier, and also to compensate the R/C compensation of the probe to accurately display square waveshapes.

Jon

My first scope I bought costed DM 1750.- (that would be about USD 900.-) Had to work 2 month for it.

I knew why I wanted it!

Dump the scope, you are not worth it.

Nick

The other two lines could be for measuring voltage. I have these on my oscilloscope. i could adjust, say, one line to mark the lowest position of the curve, and another the highest, and the scope would tell me what I need to find out the voltage amplitude. Just a guess, I only owned tektronix scopes.

Or more likely the delayed sweep. My Tek 2235 is a

The COS6100M is a solid state 5 channel, twelve trace, 100Mhz bandwith, general purpose oscilloscope. This model was actually made for the US military. Nonetheless I am sending you the manual for it in a .pdf file.

Thanks, Steve

I have a 475 and 2245.

And your point is?

I also have a 465, 485, an HP 54602B, a 7854, and probably the neatest analog scope ever made, a dual-beam 7844. With the right plugins, two complete, independent scopes in one box. Not to mention 8 channels of 100mhz plugins for my HP

I may not have a Monarch EE in the garage, but I do have a fine collection of vintage scopes.

Whoo hoo! I have oscillatory scopage! Thanks!

According to B.B. :

It looks like a nice one -- and rather closely patterened after the Tektronix 'scopes.

That is because it is not triggered. The photo angle makes it difficult to tell what the settings of the vertically-moving lever switches are. Is one of the positions on the lower-right one labeled "auto" or perhaps "free run"? If so, that is where it should be set. Otherwise, it may be on the trigger level pots. (The two at the top and bottom just to the right of the screen.) Look for a position on them (perhaps fully CCW) labeled "auto".

In any case, the "Trig'd" LED should be on when you have that setting right. It may be holding off to the left of the screen, waiting for a trigger.

Also -- look for a label on a control called "beam finder". That will show you if the traces are above or below the screen by squishing them into the visible area of the screen. You can adjust them by turning the "position" pots on the left edge of the front panel.

And I don't think that it should be displaying four traces with only two inputs, so I expect that the calibration signals are connected on the back to inputs on the back to give the trace as shown.

I think that it is working, based on your description, and just needs some of the pots set right.

You're unlikely to blow yourself (or it) up by just playing with the controls.

That is short for "Triggered". The scope holds the beam to the left of screen and blanked until it receives a trigger event (usually based on the input signal). Then it runs the beams across, resets, and waits for the next trigger.

Check that the two concentric knobs to the right are locked together. Typically, to release them, you pull the smaller one, and then it can be rotated separately. This is used for delayed sweeps, for which I don't have enough time to explain tonight.

Those are the "calibrator" outputs. You hook a scope probe to one or the other (setting the volts/division switch appropriately on the input channel to which it is connected), and it produces a square wave to allow you to verify that it is working, that the display is the right height for the voltage, and to adjust the probe (there should be one or two screwdriver adjustments in the plug) to optimize the risetime. As you adjust it, you should see the shape of the corners of the square-wave changing. You adjust them to get the squarest display which you can -- with the overshoot minimized, but the rounding of the corner also minimized.

Good Luck, DoN.

Coming down the pipe now. Thanks! Finally, email that isn't trying to make my penis larger either though photography or chemistry! I'm on dialup, so it'll take a good chunk of time to get it all, but from all of the tips in the group I've managed to get the square wave calibration thing going on the screen. Any ideas on where to get additional probes?

Sounds like you have a scope, and quite cheaply at that.

They might cost more than your scope with 1 probe did...

Electronics swap meet/ham radio club meeting/etc.

For low-tech, low frequency stuff (probably applicable, but who knows) you can make a crude probe from a chunk of coax with the right connector, an alligator clip or two, and a bit of heat shrink tubing.

Ugh. I have had VERY bad experiences with all off-brand probes. Most last about 2 weeks in light use. I have some very expensive Tek probes that I was lucky enough to get, and they have lasted over

Jon

I agree. Get Tek probes, new or old, even if you don't have a Tek scope.

Agilent (nee HP) and LeCroy probes may be OK, but I have never used them.

Joe Gwinn

Especially hamfests -- and sometimes eBay.

Yep -- except that you left out one other limitation -- you can't use the probes at higher voltages -- probably even at 120V -- you want a 10X probe for that. For logic levels, the coax and BNC connector will work -- but you are likely to have distortion at the fast-rising edges of square waves.

Enjoy, DoN.

You ought to start a thread in an appropriate forum such as...

sci.electronics.equipment or sci.electronics.repair

Or talk to an owner...

I suspect there is info on the probe - and there are many different ones out there. Might try a Tek and see what it does - likely it is only bandwidth - and some probes calibrate that!

Martin Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH, NRA Life NRA Second Amendment Task Force Charter Founder

B.B. wrote: