Scope help

Thread Starter

Treeman

Joined May 22, 2014
157
Sorry. I tested this with an analog scope. You cannot get any meaningful results at 1Hz.
At such low frequency you will have to resort to a period measurement.
Time to brush up on your microprogramming skills and build a time interval meter using a microcontroller. Nice idea for an MCU project.
That's exactly as planned actually MR Chips. I don't need to brush up my skills though 10 Print Treeman, 20 Goto 10 (return but no comma right). See -I've lost nothing.
I'm waiting for parts from Les Chinoise . It sure would save a lot of time and eyesight.
Fortunately the crystals arrived last week so I can have a go dividing in binary- gulp.
 

JohnInTX

Joined Jun 26, 2012
4,787
In the old days - pre DSO/fast analog storage scope, we used persistence of vision to see slow / one shot signals.

We used a scope hood that blocked out ambient light and kept eyes stable, or you could turn off the room lights and hold still. Set the scope for triggered single trace. Let your eyes become accustomed to the dark and increase the graticule light to the minimum you can see. When you are ready, arm the trigger. The trace will persist in your vision for a second or two. First set the trigger edge on a graticule line then focus on where the next edge should be vs the graticule. Just concentrate on the trailing edge vs the grat line. You'll have to learn to find things like the trigger arm button in the dark...

It isn't optimum but it worked for me - until some knucklehead hit the power switch on the Xerox 1000 copier - all relay logic - *flash! - bright! ouch!* I do love my TDS420..

A fun ditty on the Tek555 on EDN - the scope we had at the time. Dual beam, 33MHz, fast (P5?) phosphor for photos.. definitely stylin' and 1100 watts power consumption kept the lab nice and warm too.

Have fun.
 
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JohnInTX

Joined Jun 26, 2012
4,787
What is that Huge thing John ???? :eek:
Are you really just going to serve up softballs like that?? :cool:

Yes. Well, its a TEK 555, less power supply which was about 1/2 the size of the scope, riding on the lower shelf of the cart. The 4 modules beneath the CRT are various plug-in timebases and vertical sections. This looks like dual 1A2 two-channel units for a total of 4 channels on the bottom. Dual timebases above I think.
 

dl324

Joined Mar 30, 2015
16,846
Hi,

Didn't see this suggested.

Build an oscillator with a frequency you can easily measure on your scope (1KHz or so). Connect your 1KHz oscillator to a counter (e.g. frequency counter or a couple of cascaded binary/decade counters; depending on the accuracy you want), use the pulse from your 555 as a gate. Count on the counter should be accurate to a couple counts.

If you don't have a frequency counter, you can build an inexpensive one with a dual counter (like 74*390/393 and use a BCD/Hex to 7 Seg display). That'll give you a count of 100 or 256, depending on whether you go with decade or binary counters.

If the output from your timer circuit isn't a square wave, you could run it through a flip flop to get a half frequency square wave.
 
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