Superscan PI

[ZOUjiarui]

The machine has a pit, I found the problem, I want to rebuild it.

pcb

[ZOUjiarui]

The machine has a pit, I found the problem, I want to rebuild it.

[ZOUjiarui]

I'll measure it carefully until I find a mistake.

[eclipse]

What circuit do you use? If you just solder parts on the board and call for help is not a good idea. No one would be able to help you with this.
Provide more information about the circuit you're using /schematic not PCB/.
After that verify +5V and -5V as starters. Measure the TX signal on mosfet gate /no coil connected/.
Next steps would be preamp out, integrator out /then SAT which is a bit more specific stage to Eric Foster's designs/ but lets see first things first.

[Qiaozhi]

Hello, a master told me as long as the adjustment 709 next to the 100K resistor, you can give me more explanation, thank you!

There's no point trying to fix the problem using guesswork. You should have built the detector in stages, and tested each stage before moving on to the next one. The only solution for you now to is follow a logical fault finding approach as outlined by Carl.

If you really don't understand correct fault finding procedures, then you should seek first-hand help from a friend who does, as it will be enormously difficult for anyone here to assist you remotely.

[ZOUjiarui]

Generic PI Debugging:

1. Make sure all the power supplies have proper voltage. Especially if you have a charge pump.

2. Check all pulse timings to make sure they are correct. Not just edges, but also levels.

3. Measure the TX waveform (be careful not to overdrive the probe or scope); verify turn-on and flyback.

4. Measure output of preamp; verify correct waveform.

5. Check demod output(s); they should be steady and approximately mid-voltage without a target. Wave a target and they should respond.

6. From there it depends on the design, but mostly check the following SAT, gain, threshold, and audio stages.

Hello, a master told me as long as the adjustment 709 next to the 100K resistor, you can give me more explanation, thank you!

[Carl-NC]

Generic PI Debugging:

1. Make sure all the power supplies have proper voltage. Especially if you have a charge pump.

2. Check all pulse timings to make sure they are correct. Not just edges, but also levels.

3. Measure the TX waveform (be careful not to overdrive the probe or scope); verify turn-on and flyback.

4. Measure output of preamp; verify correct waveform.

5. Check demod output(s); they should be steady and approximately mid-voltage without a target. Wave a target and they should respond.

6. From there it depends on the design, but mostly check the following SAT, gain, threshold, and audio stages.

[ZOUjiarui]

I would like to ask the master, whether it needs outdoor debugging? It makes a sound, but these are the only two positions that can change the sound. Thank you

[ZOUjiarui]

[ZOUjiarui]

Do you have an oscilloscope? Do you understand electronics?

I am an electronics enthusiast and a novice metal detector maker. I have a small oscilloscope. Do you want to set the frequency of a coil to 500hz? Thank you

[Carl-NC]

Hello, I made it, I can't debug it, can you help me?

Do you have an oscilloscope? Do you understand electronics?

[ZOUjiarui]

specs

The settings for the Superscan are as follows -

TX pulse width 500uS

TX pulse frequency 86 pulses per second.

Sample pulse delay 60 - 150uS, adjusted by reject control.

Delay for second sample pulse 1100uS

Sample pulse widths 45uS.

The coil inductance should be 500uH for TX and RX, with a TX resistance of 1.5 ohms, including the cable.

Because of the low pulse rate and wide spacing between 1st and 2nd sample pulses, the unit can be affected by low frequency rf signals and power line noise. The MK2 version has a TX frequency control that can often counteract this. Also the integrator TC is adjustable (response speed) - slower smooths out the noise more.

For best signal on any object, the TX pulse width should be about the same as the decay time of the object signal. A large copper pan could have a decay time considerably longer than 500uS and not give as good a range as a similar size object of less conductive metal.

Ground signals from iron mineralised ground will be strong with a single TX/RX coil, but the Superscan was also designed to use separate TX and RX coils. An outer TX with and inner RX of half the diameter will give much less ground response. Also you can lay a big 10m x 10m TX coil on the ground, and search within it with a 0.5 or 1m RX.

Eric.

Hello, I made it, I can't debug it, can you help me?

[loukilouk]

Ok my friend, thank you!!!

[kt315]

Eric Foster's HD was crashed, all files were lost in moment. absolutely all. he did not archive the files. no PCB, no schematics,
no diagrams. just ITMD is stayed like a monument of basalt. strong and hardest. on centuries.

ANATLOY

[loukilouk]

Nothing?
Nothing?