Making basic test equipment, need help.

[Dazza]

I would like to try to avoid using a DMM with this Zener diode tester. May be a row of LEDs? Help on how I can do this please :-\.

Any help will be appreciated.

View attachment 36196

 

[audioguru2]

Hi Dazza,
I first thought of using an LM3914 10-step LED voltage indicator, but even using two cascaded, the output resolution would be very coarse.
Perhaps a 10-bucks LCD digital voltmeter module is best.

 

[Dazza]

Hi audioguru,
I am being ambitious ;D, I'm trying to put four different types of test equipment into one unit, zener diode tester, mosfets tester, transistor tester and 555 timre tester. Not much room for a LCD ;D. If I have to I well use a DMM , although it would have been nice to not have to.

 

[steven2]

good work dazza i allmost forgot i allso posted sometime ago the 556 ic tester to in the forums. ive got the circuits to biuld the crystal tester to and others so if you need anything email me or let me know, and if ive got it, i shall supply

 

[ante1]

Dazza,

Have you got any MOSFET tester circuit, or are you building just one at a time? Here is some stuff to look at: http://www.geocities.com/yukselesen/mosfet_tester_project.htm And here is another:

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[Dazza]

This is what I have so far, I haven't checked it four mistakes, I'm not finished with it yet . I think it will be best to make them individually and as small as I can, so I can fit them into one small unit.

Ante, I did consider that circuit that you posted, but I decided that the one steven posted, would suit my needs for now. I'm only considering my needs for the task ahead for now ;D.

steven, I would like to have a look at that crystal tester circuit that you have . I may be able to fit it in their somewhere ;D. I see you are getting serious with your hydrogen experiments, it is looking good Steven 8). Be careful with using PVC, if you get over pressure or an explosion. The PVC will shatter into pieces, it will be like 100 knives flying at you , I hope you can run fast ;D. Maybe putting the unit into a Haitian bag.

Any suggestions or improvement ideas, is very welcome .

Thank you.

 

[steven2]

here it is dazza, crystal tester

View attachment 36208

 

[Dazza]

Thanks Steven, it doesn't mention the gauge wire to use, or the size of the ferrite bead ???. maybe it's not that important. I put together the transistor tester circuit, it works very well . One down 4 to go ;D.