A soldering iron can be a tech's best friend. You never know when you need to repair an electrical connection. You can actually do a whole lot more, You can rescue parts for reuse. You can build your own simple test equipment. You can even build your own projects. You do not have to get a fancy soldering iron at first, but later as you gain experience, You may certainly want one. You also will want to learn about electronic symbols so that you can understand at least simple schematics.
Step 1: Continuity Tester.
A continuity tester is an item of electrical test equipment used to determine if an electrical path can be established between two points;[that is if an electrical circuit can be made. The circuit under test is completely de-energized prior to connecting the apparatus.
Step 2: Ttl Polarity Tester.
A polarity test is used to find out the electrical polarity (positive or negative) of the voltage.
The second project was to make a polarity tester. I wanted to know which side was positive and which was negative. Two leds (resitors if needed) and test leads from a dead volt/ohm meter was all that was needed here. If the red lead was connected to the plus or positive side of a connection (black lead should be connected to ground) the the top led would light. If the wiring were reversed then the other led would light. Great for testing diodes to see which way the should be conneccted to a circuit. You can als test low voltage batteries to see which is the plus (+) and negative (-) sides.
Step 3: Ttl Logic Tester.
A logic probe is a hand-held pen-like test probe used for analyzing and troubleshooting the logical states (Boolean 0 (0 olts) or 1 (5 volts)) of a digital circuit.
1 - 74ls367 IC (integrated circuit)
1 - 16 pic Socket for the IC.
1 - Breadboard in breadboard format. (i.e. Radio Shack Model: 276-159 or Model: 276-150)
2 - Led's s/b different colors. (i used the same color leds but wrote on the board which was which.)
2 - 1 k resistors (1000 ohms)
3 - Alligaor clips
Wire for connections and connectors.
Solder the socket in first.
Solder in diodes carfully noting which way they should be attached.
Note: if you use a breadboard socket such as RS Model: 276-003 then no soldering is required.Plug and play.
Playing with the parallel port. if the data line (2-9) is trn on the "hi: led will turn on. If it is not then the :low led will turn on. You can only test one line at a time.
Note: it can be used with microcontrollers also, not justt he pc parallel port.
Step 4: All in One Case.
Put everything in a small box that can fit in your pocket and you have your testing tools with you at your beckoning.
Note: battery should be kept in a small plastic bag s it does not get shortedout in the box.
Step 5: Planned Logic Probe.
Step 6: Signal Generators.
Collected circuits I plan to mod and build.