[time-nuts] huntron tracker advice & troubleshooting withoutschematic advise

[phil]

----- Original Message ----- 
From: "Patrick" <optomatic at rogers.com>
To: "Discussion of precise time and frequency measurement" 
<time-nuts at febo.com>
Sent: Tuesday, November 25, 2008 7:39 PM
Subject: [time-nuts] huntron tracker advice & troubleshooting 
withoutschematic advise


> Hi Everyone
>
> I have consistently had success repairing laboratory instruments(my
> small business) when I have a schematic and I have consistently failed
> without one, lots of opportunities are slipping threw my fingers.
>
> I want to invest in tools that will help me troubleshoot without a
> schematic. I was thinking about getting a Huntron tracker. Has anyone
> had any experience with one? Could you feedback?
>
> Are there other tools that have helped you fix circuit boards without a
> schematic?
>
> Thanks in advance-Patrick

Patrick,
We have used that technique of quick troubleshooting some components off an 
on for forty years, long before the "Huntron tracker came about.

I first saw an article about that method in a service bulletin from Sylvania 
back in the mid 60's.
If you have an x-y scope or a scope that has and external horizontal input 
with variable gain, a small external circuit in addition to the scope will 
do the same thing as the Huntron tracker. This would give you the ability to 
play with it without spending any money.

The circuit consists of a transformer with 3 to 6 volts out, a few 
resistors, diode or two and a switch. If needed I could find the original 
schematic, but doing a google on it turned up a couple of links, noted 
below.

Inexpensive Curve Tracer
http://www.fisica.ucn.cl/sochifi/actas/pdf/A039.pdf
http://groups.google.com/group/rec.audio.tubes/browse_thread/thread/384a37553565e87b

As others have noted in this thread, it doesn't fix anything but can be 
useful in "some" applications. It will quickly identify a short or open and 
with experience, identify most defective "discreet" semiconductors. In the 
case of complex IC's, I doubt it would be much use. If you research the 
Huntron tracker display results, you will see the patterns displayed in 
various semiconductor situations.

As a general rule, servicing electronics, or about anything is simply a 
logic and deduction process. Basic knowledge of the components, theory of 
operation, and of the circuit under test is still necessary.

Phil