Anyone used one of these?

[Cursitor Doom]

Given the shortcomings of low power battery testers/meters for checking
certain components that typically run at considerably higher working
voltages where any fault may only become apparent, has anyone any
thoughts on the utility, or otherwise, of these devices?

http://www.ebay.co.uk/itm/Transistor-Diode-Curve-Tracer-Component-Tracker-
Tester-Probes-BNC-Cables-/161294643173?
hash=item258de8efe5:m:miccP4BhvzYiDpcErFn7FDw

[gghe...@gmail.com]

Never used one.. but it says octopus. I recall this curve tracer that
a navy tech showed me once. A couple of transformers and R's..

Google octopus curve tracer and maybe you'll end up building on of your own.

George H.

[Cursitor Doom]

Thanks. I wouldn't have thought there was much to these things,
especially since they rely on an external scope display. I'm just curious
as to how useful they are compared to more common test kit.

[Ralph Mowery]

"Cursitor Doom" <cu...@notformail.com> wrote in message
news:n87u5i$4lt$5...@dont-email.me...

All this ammouts to is a transformer, capacitor and resistor in a box. Just
do a search for an Octopus component tester. Years ago it was of some use
and may be today if you have a known good board and one you are testing.

Today there are much beter component testers out. For about $ 20 you can
get the circuit board of a component tester that is much beter for testing
components out of the circuit.

This ebay number is one of many of them.


291585134524

[legg]

Common commercial unit is the Huntron 'Tracker' with built-in display.
Can be of some use on production test bench, but doesn't replace
visual inspection and simple open/short or bias testing.

RL

[Cursitor Doom]

On Tue, 26 Jan 2016 10:08:48 -0500, Ralph Mowery wrote:

> This ebay number is one of many of them.
>
>
> 291585134524

Thanks Ralph.

[Cursitor Doom]

On Tue, 26 Jan 2016 10:28:21 -0500, legg wrote:


> Common commercial unit is the Huntron 'Tracker' with built-in display.
> Can be of some use on production test bench, but doesn't replace visual
> inspection and simple open/short or bias testing.
>
> RL

Nice - but a bit pricey!

[Mark Zacharias]

"Cursitor Doom" <cu...@notformail.com> wrote in message

news:n893ri$8su$4...@dont-email.me...

I keep a home made "octopus curve tracer" (two-lead type) on a dedicated
scope for the past 30+ years.

Absolutely WOULD NOT be without it.

Instantaneously find one bad amp channel out of many, very quick checks of
capacitance, inductance, resistance, diodes, fets, transistors, etc.

Once you get used to it and sort of "get it" as to what the device is
telling you, it will make you a better, faster technician.


Mark Z.

[Cursitor Doom]

On Wed, 27 Jan 2016 06:24:46 -0600, Mark Zacharias wrote:

> I keep a home made "octopus curve tracer" (two-lead type) on a
> dedicated scope for the past 30+ years.
>
> Absolutely WOULD NOT be without it.
>
> Instantaneously find one bad amp channel out of many, very quick checks
> of capacitance, inductance, resistance, diodes, fets, transistors, etc.

And it's capable of testing these components at their intended working
voltages and currents? This seems to be the main shortcoming with almost
all the small battery powered testers.

[Mark Zacharias]

"Cursitor Doom" <cu...@notformail.com> wrote in message

news:n8bch7$fo6$6...@dont-email.me...

Mine uses a 6.3v AC transformer so no attempt is made to operate devices
under load.

mz

[Cursitor Doom]

On Wed, 27 Jan 2016 20:46:54 -0600, Mark Zacharias wrote:

> Mine uses a 6.3v AC transformer so no attempt is made to operate devices
> under load.
>
> mz

But you still find that exposes every form of damage you encounter in
practice?

[Mark Zacharias]

"Cursitor Doom" <cu...@notformail.com> wrote in message

news:n8cv5k$3i4$3...@dont-email.me...

I never said "every form" but it is a powerful tool.

Like oscilloscopes.

Like multimeters.

Like an esr tester. (Even though the "curve tracer" can give a quick check
of esr in many situations.)

It's usable in-circuit and once a person is proficient with it, can VERY
often cut troubleshooting time dramatically. (Test current is
resistance-limited, depends on exact schematic of the curve tracer. There
are many variations.)

We all have our favorite tools and little tricks to help us in what we do.

This is just one more.


Mark Z.

[Mark Zacharias]

http://www.techlib.com/electronics/curvetrace.html

A sample curve tracer "octopus" schematic.

mz

[Cursitor Doom]

Thanks, Mark. I'll take a look on youtube see if I can find any tips on
how to use these under practical conditions to take in-circuit
measurements. I have more than enough scopes here with x-y/comp tester
inputs.

[legg]

Hence the jig on offer. Just add your own uncommited oscilloscope...

You won't want to hook it up and disconnect it every time you need to
switch over.

RL

[jurb...@gmail.com]

We used to make those out of a 6.3 volt transformer and a couple of resistors.

Later I figured out a neater one for caps. You need a 1 KHz square wave of 400 mV with as close to 350 ohms source impedance as possible.

I can check caps with it from about 0.47 uF all the way up. If you can manage to, have the 400 mV square wave ride on 200 mV DC and it will also automatically detect shorts.

It is way faster than any ESR meter out there, even the old Wonderbox. Once you learn how to read it that is. And it is easier to see than almost any analog or digital display.

One of these days I plan on doing a writeup on it but I want to get a bunch of pictures depicting the readings on good and bad caps of a bunch of different values.

[Cursitor Doom]

Sounds like a useful addition to any test bench. I've probably already
got a suitable transformer lying around waiting for just such a project.
Plus no shortage of "uncommitted oscilloscopes." :)