Spa Computer Help

[DaJMasta]

And it's sort of off topic and very much a matter of preference, but even if you think a logic probe is an essential tool for your kit that you want a quality version of..... if there aren't any available and you just need to check oscillation, a basic circuit and a breadboard will do just fine.

And honestly, if I've gotten to the point that I need to know if the oscillator is working right, I'd much rather see the waveform on the scope and getting a probe out of the drawer takes about as much time as booting up the scope.  I've had access to a logic analyzer since I was a kid (my dad was into electronics too), but I never bought one for myself.  A simple circuit, a multimeter with an AC mode or a duty cycle readout, or a scope or other simple digitizer all will suffice and it's very rare that I want to see only the binary signal on a single bit (logic analyzer isn't worth it then) and don't care about the waveform, so I haven't found the need for it.


Anyways, it's neither here nor there, in a pinch (it sounds like the OP is in one of sorts) building the circuit to check basic operation is an option.  If you then choose to have and use a logic probe, go right ahead.  Even a spare micro would do in this case, just reading off a pin and displaying it over a serial port would give you a good idea if there's activity.

[vortex_690]

Hi all

Look what i found

Next question how to use it

[Armadillo]

Great find. Can it be turned ON?

its a dual trace 25Mhz scope.

Transistorized.

But make sure its working safe before you poke the board.   

[vortex_690]

Hi all

I finally got my logic probe from china

Should I have on ttl or cmos

where should I test and I have connected the the power to the 5v line and a neg

[Armadillo]

Hi all

I finally got my logic probe from china

Should I have on ttl or cmos

where should I test and I have connected the the power to the 5v line and a neg

Slide to pulze mode,
Slide to TTL
Probe the tip onto Pin 10, you should see blinking Hi and Low [or both lighted because too fast].
The last time you measured Pin 10, it was close to 5V, so I reckon only Hi lighted if you have not changed the resonator.

[vortex_690]

As soon i make contact with pin one light flashes then nothing...I have changed the blue resonator

[Armadillo]

As soon i make contact with pin one light flashes then nothing...I have changed the blue resonator

Touch the probe tip to 5v, red lighted.
Touch the probe to the ground, Green lighted.
Touch the probe to Pin 10?

Please be specific, there is the Red Led, Green led, Yellow LED on the probe, which one lighted?
nothing, do you mean, non of the LED lighted?
What Pin did you measured?
Measure Pin 10 with a volt meter, how many volt is on Pin 10?

Be careful of the positive and negative crocodile clips, they can bridged onto other circuit pins nearby. I changed mine to the claw type instead of crocodile clip.

[vortex_690]

Hi Guys

Ok when I touch the probe tip to the 5v ,ground or pin 10 I get a single yellow light flash once then no light


the pin 10 has 4.96v

[Armadillo]

Hi Guys

Ok when I touch the probe tip to the 5v ,ground or pin 10 I get a single yellow light flash once then no light


the pin 10 has 4.96v

I don't understand what is "no light" when the photo shows the yellow light is lighted up.? this usually indicate oscillation.



if you touch the 5v, you should see Red light



If you touch the Gnd, you should see Green light.



And if you use your finger to touch the tip, all should light up, red, green and yellow.

If you cannot get it, check your power supply connection and voltage. If still cannot, then return the probe to ebay.

Do update your profile so that the community can know where you are from.

[vortex_690]

The single yellow led on the probe lights up only for 1 second as soon as i make contact but then goes off then nothing

Would the 5 volt source be enough or would i need to use a 12v

If i touch my finger to the probe the yellow light comes on and flickers like a heart beat or something

[Armadillo]

The single yellow led on the probe lights up only for 1 second as soon as i make contact but then goes off then nothing

Would the 5 volt source be enough or would i need to use a 12v

If i touch my finger to the probe the yellow light comes on and flickers like a heart beat or something

5 volt is enough for TTL circuit [this circuit].
If you touch with your finger the RED and the GREEN should also be lighted with the Yellow. Right? Is the RED and the GREEN LEDs working? Try touching to 5volt and then Gnd.