I have a multimeter that has a sign on it, but I don't know what I can measure with it.
It looks like a small square wave:
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I have the EM393B multimeter.
I know it's not for: volts (alternating and direct), amps, ohms, diodes and continuity.
See page 14 of the Users Manual - it puts it in the "test signal" output mode.
Thanks for the help!
What will the test signal output do?
Will it send out a signal or measure signals?
If it sends out a signal, why would you want a multimeter to do so
and signal will it send out?
The user manual says:
The output voltage is approx. 5 volts p-p with 50k impedance.
So will it give 5 volts or a signal with max 5 volts?
What does the p-p mean?(Per pin?)
Thanks for the help:)
Floris
p-p (or pp) means peak-to-peak. So voltage difference between the lowest level and the highest level of the output signal.
An output will never measure (except maybe for the current that is drawn from it). It's an added feature that in principle does not belong in a multimeter; but it can be useful; alternative is to add a far more expensive signal generator to your equipment.
It generates s square wave, like the once popular "signal injector"
A contemporary circuit would use a 74HC14 - it is an indication of just how "antique" that this concept is, that I cannot find such a circuit on Google!
The concept of a square wave is that it has essentially unlimited harmonics (depending on its "squareness"), so that whilst oscillating in the audio spectrum, it will generate a signal for radio receivers up to perhaps hundreds of Megahertz.
That meter is unusual in several ways, not the least of which is that it has the 10A test port on the right hand side - most I've come across locate this feature on the left hand side, away from the normal voltage input.
I was only commenting on units I'd come across 
But if you want to be picky, would you trust those leads at 1000V DC :o
Context.
The meter first cited only claims 250 V. It is not a Fluke.
I was making a simple comment of observation with respect to the OP input - it was your good self who decided to go off on a tangent by illustrating a meter to counter my observation.
Let's politely considered the matter closed
Paul__B:
It generates s square wave, like the once popular "signal injector"
It's been a LONG time since I've seen this oscillator circuit.
I last used something similar to regenerate horizontal sync pulses from 1980's era "scrambled" TV signals.
The sync pulses were AM modulated on the sound carrier and they were short (needed to be pulse stretched to the width of the horizontal sync pulse... including both "porches".
The scrambling method was to level shift the sync pulses up into the video range so that the TV couldn't lock onto it, but receiving the timing pulses off the sound carrier, then stretching them to the right length, then applying them to the video to DC shift it back to normal is what made it work.
I made a lot of $$$ on those boards back in the day.......
Well, that's the game, isn't it?
One side makes it difficult to use, so they can make more money selling a crippled service, the other makes money making it work again.
In Phoenix, AZ, UHF channel 15 was scrambled by suppressing the sync pulse with a sine wave after 7pm, when it became OnTV, a pay service.
HBO and Showtime were broadcast on about 2.15GHz from South Mountain, one in the clear, the other scrambled the same way OnTV was.
I made a few descramblers and microwave downconverters. I had fun making a variety of 2GHz antennas.
Ah, reminiscing ...
When life was analog and comparatively simple.
polymorph:
In Phoenix, AZ, UHF channel 15 was scrambled by suppressing the sync pulse with a sine wave after 7pm, when it became OnTV, a pay service.HBO and Showtime were broadcast on about 2.15GHz from South Mountain, one in the clear, the other scrambled the same way OnTV was.
I made a few descramblers and microwave downconverters. I had fun making a variety of 2GHz antennas.
Yeah, we had that too (different cable provider).
The sine wave was AM modulated on the sound carrier and it had to be amplified and fed to a resonant L/C circuit (resonant at 15734 Hz) and then the coil slug was adjusted to get the sine wave PHASE to match with the scrambling sine wave applied to the video (180 degrees out of phase, of course), PLUS an amplitude adjustment to properly null it out.
I preferred the digital version (the level shifted horizontal sync pulses with the reconstruction pulses AM modulated on the sound carrier). All you needed was to detect the pulses, then stretch them to be as wide as the "scrambling" pulses and add them to the video.
Actually, the correction signal was added to the video at the RF level! There was a T-pad inline with the cable RF path and a diode switch (dynamic impedance) to either RF ground or RF float the bottom of the T pad which, in effect, AM modulated the RF signal and removed the scrambling pulses.
Ah the good old days when things were simple and you could get away with a few things here and there. Not so easy anymore.....
Watch Dave ranting on cheap Chinese Multimeters
