Suggestions wanted - Your handy dandy testing station

[Mark Hammer]

Most of us have meters, and some even have scopes and other high-falutin' stuff like distortion meters.

But there are a lot of little pesky tasks that come up again and again, that either meters don't do, or do well, or do without help.  What if you could build yourself a "swiss army knife" of adjunct test functions, that sat in one chassis, and you knew that 95% of the things you want to measure/assess/rank/verify (and regularly need to do) could be done either with that chassis alone, or by sticking your meter probes into sockets for the probes and flicking a switch or two on your magic box, in conjuction with using the right sockets and settings on the box?

What would such a unit consist of or include?

Things that immediately come to mind are:

• JFET Vgs tester (for matching)
• bipolar matcher
• bipolar leakage measurement
• hfe measurement of transistors with uneven lead lengths or unusual pin spacings
• capacitance measurement of caps with leads that don't fit your meter
• audio cable continuity testing
• optimal LED current-limiting resistance
• circuit current draw

But there are likely a host of other simple-but-important tasks that you folks find yourself regularly having to rig something up temporarily to do.  Again, I'm thinking of fairly routine sorts of tasks that could be installed into one big chassis such that they don't have to be a haphazard little tool/rig that you need to dig around for or set up.  Heck, it could even be built into a box with a regulated variable supply.

So what would you add to this dream tool?

[tubegeek]

I wouldn't mind an inductance meter.

[Mark Hammer]

I assume you mean something that could hold inductors while you measure them with your meter?  Or do you mean an inductance-measuring function that incorporates signal generation?

Hmmm, that's another thing to put on thelist: simple signal generator.

[GGBB]

Diode forward voltage measurement at small currents.

Op-amp tester.  Primarily duals, but singles would be nice too (quads not necessary).

Cap leakage tester.

[arma61]

• Transitor-JFET-MOSFET-ANYFET Pins detector
• 13/64 inch Loud(?)speaker

ok a beeper would do 

[Pojo]

JFET Idss and Vp testing would be on mine. Also the hfe/leakage testing for those into the germaniums. Maybe some sort of way (socketed chamber maybe) to measure light/dark resistance of ldr's?

[Hemmel]

Following Digi2t's advice, I bought this transistor tester and it's absolutely awesome !
There's the DCA75 version that can connect via USB to a PC/MAC software but it's over twice the price of the DCA55.

This other tester seems good for testing passive components, could be good for Gord's need for Fwd Voltage testing.

[Seljer]

Something not just to test transistor hfe but whether or not it actually works at all (because my desk is littered with dead BJTs that I don't through away because I think "I'll use it as a diode!" and then they creep back into my drawer of good transistors)

I wouldn't mind an inductance meter.

I've built a simple capacitance and inductance meter with an Atmel microcontroller and a comparator chip (some PICs have the comparator already on the IC so that saves some board spacE). The issue is that it's mainly aimed at lower values (it can measure microhenries and picofarads very well but the circuit doesn't oscillate properly above 220nF or a 100mH or so)

[electrosonic]

The Peak DCA is great for bipolars but gives minimal info on jfets.

I have looked at a few people's suggestions.

I kind of like this one

http://www.edn.com/design/other/4370552/Simple-circuit-lets-you-characterize-JFETs

Keep meaning to do a board in Eagle and get it fabbed.

I have this cheap led tester - but the currents marked on the box bear little relation to what it actually sources. (which makes is sort of pointless)





Andrew.

[pappasmurfsharem]

Audio probe?

[gjcamann]

How about Cap ESR. I've always been curious about how much ESR is really in those Tayda caps.

I second diode forward voltage at low currents.

And something that can figure out a BJT, regardless of how you hook up the pins.

There's some things that do this on EBAY. Anyone have one of these or something similar?

http://www.ebay.com/itm/like/141145828986?lpid=82

[mth5044]

Voltage?

[LucifersTrip]

resistance, voltage, capacitance, tran hfe, tran leakage, tran lug identifier, opamp tester, 12A_7 tester

[R.G.]

Some simple form of oscilloscope. Laptops go obsolete, and can be had for almost nothing. Generally they can run a sound-card oscilloscope.

[digi2t]

One of my best buys of 2013 was this, an inductance/capacitance meter;



Not only does it help me determine whether caps are good or not, but has also allowed me to determine wah inductor values, some of which have been mislabeled on schematics (Schaller Bow-Yoy wah for example). Combined with my DMM, it was also key in finding that LT44 transformers could be used as suitable replacements for the TDK 4 Henry inductors for the Honey Special Fuzz clone.

Should be part of the package, IMHO.   

[amptramp]

A signal tracer so you can find where the sound goes away at the input end.

A signal injector so you can find what still works near the output end.

Curve tracer.

Tube tester.

Guitar signal simulator (could be just a recording).

RLC bridge.

Amplifier + speaker.

[MaxPower]

For me it would be an op amp tester that also gives the pin out.

[Jdansti]

>Heck, it could even be built into a box with a regulated variable supply.

So what would you add to this dream tool?

A transformer? 

Sorry-I couldn't resist! 

[gjcamann]

For tranny testing, I like something that has micro-clip leads over something with a socket. Maybe have both.

Are you trying to make something to sell or just mess around with?

Either case, if you're using an AVR platform I may be interested in helping.

[Mark Hammer]

Are you trying to make something to sell or just mess around with?

Once I get my backlog of projects done, it's something I'd like to make for myself.  No doubt it would not be the same as what others might build for themselves, if only because some of the things people want to measure can be things I don't have much regular use for, or simply don't understand well enough to do anything with the information.

I guess my general intention was to get folks thinking about what they could do to co-ordinate, in a more convenient fashion, the little electronic measurement "state-of-the-circuit" tools they often use.  It doesn't have to do everything, but it helps to canvas people and think about everything that sometimes or often needs doing, so that a practical and achievable subset can be identified and packed together.

The Swiss army knife analogy is appropriate here since it only packs in simple functions that can be reasonably well-accomplished within the form factor.  So, for some folks, a little plastic box with appropriate clips and/or sockets that lets them easily measure (with their meter) any 2 or 3-lead component of pretty much any size they normally encounter, can provide enormous bench convenience.

If someone has the diligence and generosity of spirit to plan outa layout and accompanying circuit for what they feel is a close-to-all-purpose measuring tool, I imagine many here would be much obliged - myself included - but given the likely diversity of what different folks have in mind, I can't see that anyone would come up with a be-all-and-end-all package.

Still, like I say, it's good to canvas people for what would be on such a list for them.  there may well be things on that macro list that any of us might have overlooked for our own personal list.