Hello...

I would like to contribute 6 projects to this site, and I am looking for some ideas from you as to what to submit. Please tell me what you would build and what you wouldn't. Or if you have some original ideas that you would like to see brought to life then please share them with me.

Limitations:

• Under USD 100 in parts to purchase
• Battery powered
• CMOS 4000 ICs
• Common Linear ICs such as LM358
• Common BJTs such as 2N2222
• Common diodes such as 1N4007
• Microcontrollers 16F628 and 16F887
• mikroC Language
• Single sided PCBs
• Monochrome artwork

Thanx!

 

Microcontroller based IC tester, something I want to build but I have trouble with code..

 

Microcontroller based IC tester, something I want to build but I have trouble with code..

Arh what an excellent idea! So something to test common CMOS 4000 ICs?

 

Ok so project 1 of 6 is CMOS 4000 IC tester. I need 5 more guys...

 

Arh what an excellent idea! So something to test common CMOS 4000 ICs?

4000 series / 7400 series. some op-amps can work with single rail voltage, so possibly 5v rail can be used to power them up.
Besides IC, 7-segment LED displays can also be used.
All of that can be controlled by microcontroller, and if you leave instructions on how to modify the program for other IC's, then all you have to do is make it work for few of them and rest can be programmed by the user.

 

This is blue-sky, but perhaps a "learn mode" could be supported to add new parts to the machine's repertoire -plug in a known good chip and press the "learn" button.

 

Capacitance and ESR tester for capacitors.
Must measure ESR to 1 mOhm. Must test 100 pF to 10,000 uF

Transistor tester.

Light meter

Duty cycle and frequency counter.

IR emitter angle of half intensity
Photo transistor angle of half intensity

 

This is blue-sky, but perhaps a "learn mode" could be supported to add new parts to the machine's repertoire -plug in a known good chip and press the "learn" button.

HP or Fluke or somebody made something like that in the 1980's. As I remember, they did some sort of a checksum on a single signal. I sure wish I could remember what the called it...

 

This is blue-sky, but perhaps a "learn mode" could be supported to add new parts to the machine's repertoire -plug in a known good chip and press the "learn" button.

That's an high-tech solution there Dick. I cannot see the software solution for it off the top of my head though. Would it be an analogue system? I did build what is called an signature checker many years back. This is an diagnostics tool whereas you hook up leads to a part of an working board and compare the readout to the leads that are hooked up to an faulty board.

What I did have in mind was to make it specifically for CMOS 4000 digital chips. The PIC's firmware would be hardcoded with protocols for each chip. For example... say an 4017 decade counter chip was inserted, then the rough pseudo code for this C function would be:

1. Apply VDD to pin (n)
2. GND to pin (n)
3. Reset pin(n)
4. Toggle clock input pin (n)
5. Check output Q(n) for logic high
6. Loop back to #4 for (9) cycles
7. All outputs swung from low to high one at at time? Fall through...
8. LCD to show "Chip Identified as CD4107"

So with a few dozen chips hardcoded with protocols the firmware would scan through them until it found an logical match.

 

HP or Fluke or somebody made something like that in the 1980's. As I remember, they did some sort of a checksum on a single signal. I sure wish I could remember what the called it...

Ah ha. Found it:
http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1977-05.pdf

 

A better CMOS logic probe with indicators for Hi, Lo, open & pulse. Front end may use LM339 comparators.

Would be nice if able to show frequency on a 4 digit led display (up to 20 MHz) and duty cycles of the signal measured. Duty cycle would be displayed with just the On-Cycle of 0%-99% should be enough. Design with 16F628A or 16F886 (28p PIC) would be fine.

Allen

 

A better CMOS logic probe with indicators for Hi, Lo, open & pulse. Front end may use LM339 comparators.

Would be nice if able to show frequency on a 4 digit led display (up to 20 MHz) and duty cycles of the signal measured. Duty cycle would be displayed with just the On-Cycle of 0%-99% should be enough. Design with 16F628A or 16F886 (28p PIC) would be fine.

Allen

Nice idea

I did a super probe years ago for a magazine, but it was never published. It did not show frequency or duty cycle though. It did however have memory to store the high and low readings that it measured, and plugged into an computer for upload of acquisition data.

 

I would go for an ESR meter

 

I would go for an ESR meter

In Australia they sold thousands as KITs at Dick Smith Electronics two decades ago. I build one.

 

I would go for an ESR meter

I just got my ESR meter from here...
http://www.banggood.com/DIY-Meter-T...ESR-Inductance-Resistor-NPN-PNP-p-929603.html

It comes in kit form and uses ATmega328 mcu. Quite a good value for money.

Allen

 

In Australia they sold thousands as KITs at Dick Smith Electronics two decades ago. I build one.

Yes, I have a few issues of Electronics Australia in the 70s or 80s. I made the DIGI tester which included 4 bit LED display, a clock generator with selector switch for different frequencies. And 2 buttons for generating Low to High and High to Low pulses.

Not sure if there was a kit for it..

Allen

 

All been done before. The ESR meter. The IC tester. The cap meter. The super logic probe.

*bangs head against wall for original never done before ideas*