Troubleshooting Tips
    

Some preliminary comments...
The kits supported here (K108, K145, K190, and VK011) should work just fine when assembled correctly.  Yes, it's possible for there to be a manufacturing defect, or a wrong component supplied, but this kind of thing is very occasional.  Assuming the hardware is working properly, my software will work with the hardware, without any major problems.  That doesn't mean there aren't any bugs, but basic functionality works as advertised.  

Pre-testing  
Connect your kit to the computer, but do *not* connect any sensors. Start the software, and try connecting to the board. If the connection is successful, you should see something like "Kxxx found" in the Log, then it should show the rev. number for the board. If you see this, your board is likely functioning okay.  Now, try connecting sensors.  

Kit assembly  
It's absolutely critical to double- and triple-check component placement and soldering.
  - resistors -- the correct value in the correct location
      (a magnifying glass helps with checking band color)
  - if there's a resistor network, it must be oriented correctly
      (mark on the package goes to mark on the board)
  - electrolytic capacitors -- the + side inserted in the + hole on the board
  - small capacitors -- correct value in correct location
  - ICs -- notch on chip should follow notch mark on board
  - voltage regulators and transistors -- inserted right way around
  - diodes -- band end should follow band mark on board
  - soldering
      - examine all joints with a magnifying glass, making sure you 
          don't have any solder bridges between nearby points that 
          shouldn't be there (bridges are easy to make, hard to see)
      - reflow all joints with your iron, in case there are cold solder joints.   

Desoldering     
If you need to remove a component, solder wick (copper braid) and/or a solder sucker will help.  Removing excess solder first makes it easier to release component leads from the holes.  After a component has been pulled, use solder wick again to remove any solder left in the holes, so they're clear for inserting the replacement component.    
  
Multi-pin components (like a resistor network) are very difficult to remove.  There are special desoldering irons with a tip shaped to heat a strip of pins at once, but these are likely to be overkill for a hobbyist.  A simpler method is to cut/break the component into pieces with a pair of side cutters, unsoldering one piece at a time.   

Desoldering can often require excessive heat to be applied to a component.  For reliability considerations, it's probably best to replace removed components with new ones.      
  

Data connections
  - serial cables must be what's called a "straight through" type 
  - temperature sensors are polarized, it's easy to get them turned around.
      Make sure that the Vdd pin goes to V+  at the kit terminals
                  
     If V+ and Ground connections are reversed (the most likely mistake), 
     this kills any readings from the sensor.  If the Data pin is accidentally 
     connected to V+, data will keep flowing.  If you get wildly fluctuating 
     readings, or a reading stuck at 85.00, you may have a sensor with a 
     manufacturing defect (see this page for more info).  

Software  
I've had communications recently with a couple of people attempting to run the K145TMLite software on older Pentium hardware.  The Tester program would run okay, but there's an Access Violation when the Lite program starts up.  The AV is a Windows error message.  Since it happens right at startup, I think the Lite program is asking for some resource that Windows can't provide.  (Note that the Lite program uses a lot more resources than the Tester.)   One fellow was using Win98, the other Win2K, so this would suggest it might be a hardware issue with older Pentium systems.  

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