The detailed Instructions for Prof. Steven Jones with his two Atten Oscilloscopes.
Step 1: After receiving the package.
Take the oscilloscope-test-ready board from the plastic box and take off the bubble wrapping. Visually examine for any damage. If no damage, proceed to Step 2. If there were damages, post and get another board.
Step 2: Hook up for the tests assuming two Atten Oscilloscopes are available.
Use Scope A for Input and Scope B for Output. Set up Channel 1 to measure Voltage and Channel 2 to measure Current for both Scopes. Display the Channel 1 Vpp, Channel 1 Vrms, Channel 2 Vpp, Channel 2 Vrms and Channel 1 Frequency on the RHS of the screen as displayed in the BMP scope captures.
Step 3: Connect the Scope Probes to the board as displayed on the picture at the bottom of the board (also shown here)
Scope A Channel 1 positive hooked to ring marked A1. This is also the connection for the positive end of the DC Power Supply. Scope A Channel 1 negative hooked to ring marked (A2, A3, B2, B4). This is the common ground connection. Scope A Channel 2 positvie hooked to ring marked A4. This is also the connection for the negative end of the DC Power Supply. Scope A Channel 2 negative hooked to ring marked (A2, A3, B2, B4). There is no typing mistake. The current direction is indeed connected as A4 to A3. Thus, the Channel 2 invert function should be turn to ON. This is the technique used to ensure common ground for the two Scopes.
Scope B Channel 1 positive hooked to ring marked B1. Scope B Channel 1 negative hooked to ring marked (A2, A3, B2, B4) Scope B Channel 2 positive hooked to ring marked B3. Scope B Channel 2 negative hooked to ring marked (A2,A3,B2,B4)
Step 4: Connect the DC Power Supply and start tuning
Connect the DC Power Supply with positive to ring marked A1 and negative to ring marked A4. Turn on the power, starting from 0 volts to 1.2 Volts as seen on Scope A Channel 1 Vrms. The LED should start lighting up at around 400mV and reach full brightness at around 1.2V. The LED will remain ON even if the DC Power Supply is turned OFF for at least 2 minutes (prototype passed time). Turn the DC Power back ON and wait for the frequency as indicated by Scope B (bottom display value) to reach 10KHz approximately.
Step 5 (to be continued)
At this point, compare the waveforms on Scope A and Scope B with those shown below. The Output Channel 1 (Scope B) Vpp, Vrms should greatly exceed that of Input (Scope A). This is expected as the Output Voltage must somehow exceed 3V to turn the LED rated at 3V ON. The Output Channel 2 (Scope B) Vpp, Vrms should also exceed that of Input (Scope). This will indicate good possibliity of Output Power greater than Input Power. Remember: Instantaneous Power = Instantaneous Voltage x Instantaneous Current.
Do not congratulate yourself yet. You have not done Step 5 and beyond.
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