Last post by jvthorsley - September 19, 2023, 02:59:32 PM
Good writeup Curtis just goes to show the hazards of charged up Capacitors on a circuit board. To test for this hazard the ESR Capacitance Meter from Peak Electronic Design Ltd will attempt to discharge the voltage up to 50 Volts and warn the user if voltage is higher. But manually discharging capacitors first is recommended.
Another hazard running my ProTrack + Scanner with work station 4.3 I found that switching off my old Weller Solder Iron, that's the one with 24 Volts A.C. supply transformer would cause some very peculiar results on Workstation. One obvious thing was the trace was displayed in a very distorted form. Fixed this by installing a transient suppressor across the mains input.
Last post by admin - September 19, 2023, 07:46:56 AM
We have seen a minor surge in the number of Tracker repairs where the main board has been damaged by a voltage applied through the probes. Maybe this is a good time to revisit the topic by sharing Quick Tip #21 from the Huntron website.
Quick Tip #21: Protecting your Huntron Tracker The most common reason a Huntron Tracker comes to the factory for repair is because it was subjected to a voltage or current surge through the front panel probes. Sometimes the damage is minimal and other times quite severe. Huntron Trackers do have front end protection that is triggered when a voltage higher than 20Vpk is applied through the probes. When the over-voltage protection circuit is triggered the channel and range relays are set to an open state in an attempt to protect the Tracker. In most situations this protection functions quite well but in cases where the applied voltage is lower but the current available is high then the Tracker is at risk. This is usually the case when a charged capacitor is tested. The voltage potential may be low but when the capacitor is probed then it discharges through the Tracker. Damage can occur if the Tracker is set to a low resistance such as 10 ohms and in most cases the repair involves replacing damaged range resistors and relays. In cases where a live circuit is tested with a Tracker the damage can be much worse. Users have told us that they have multiple sets of leads going to different instruments on their bench. When going to test a live circuit they accidentally grab the wrong probes, the Tracker probes in this case. We have seen upwards of 220V applied to a Tracker with predictable results as shown in the images below. Severe damage to the main Tracker PCB can result and in many cases requires the PCB to be replaced.
Exploded electronic components
What can you do to protect your Tracker? Establish a set test procedure that reduces or eliminates the possibility of applying an external voltage to your Tracker. - Disconnect any external power sources from the unit or circuit board under test. This can especially apply to Access Prober users who are automating power-on test measurements (i.e. DMM and oscilloscope). - Disconnect the board under test from other boards or power supplies in the assembly to help isolate it and reduce the risk from external voltages. - ALWAYS safely discharge large capacitors on the circuit board under test before using your Tracker. - If you have multiple test instruments on your bench find a way to distinguish which probes go where. Maybe have unique marks or colors. - Disable or disconnect batteries or "super caps" that may be on the circuit board. This will also help in getting more stable signatures.
Prevention is the key to keeping your Tracker safe and avoiding expensive repairs.
Contact Huntron Technical Support with any questions.
Last post by Al1234 - September 07, 2023, 08:59:53 PM
oh ok, short finding. I got it. thank you . Back to the main subject, the Shortrack, correct me if i am wrong, but I think the connector for the lead is a Mini XLR 3 Pin Female Solder Connector, part number RT3FC-B.
Last post by jvthorsley - September 06, 2023, 10:01:35 AM
The Polar Toneohm 950 is very useful for finding shorts. The ProTrack will tell you there's a shorts across a power line. And the Toneohm 950 will tell you which of the many decoupling capacitors is the cause of the problem. You can even put probes at the four corners of a circuit board and close in and locate a short across bus plane. I don't think I'm upsetting Curtis here as Polar no longer manufacture the Toneohm 950. But they do still supply the Probes. And just to show how old the 950 is it uses a Z80 Zilog microprocessor. But this does not detract from its usefulness in the workshop. The i-prober 520 is very useful for working on switch-mode power supplies and no danger of shorting things out with a current probe. Sorry Curtis gone off-piste a bit here!!
Last post by Al1234 - September 05, 2023, 05:52:00 PM
Package arrived, got the shortrack. it turns on. but there is no battery compartment. it probably needs to get opened up. No leads either and anyone knows what type of connector is that on the board, please?
Jvthorsley, Thanks. this may be going off the subject for this thread but. I looked up the i-prober 520. I like it. looks like this one measures amp! I will put it in my wish list. I am very curious how do you mean Polar toneohm 950 is a useful companion with ProTrack? how and what do you use it for, while diagnosing?
Last post by jvthorsley - September 01, 2023, 03:38:18 PM
The Polar Toneohm 950 makes a very useful companion to the Huntron ProTrack. I was lucky to get one through Ebay from Florida with all the Probes. Thurlby Thander Instruments also make a current Probe under the name i-Prober 520 current Probe. But the Polar is far more flexible to use.