What voltage should be read on each pin of the power adapter?

1. Central Pin: In many laptop power supply connectors, especially those using the barrel-type connector, there's a central pin that carries the voltage (typically around 19 volts for most laptops) to power the device.
2. Voltage and Polarity: It's crucial to ensure that the voltage supplied by the power adapter matches the requirements of your laptop. Most laptops operate on 19 volts, but there are exceptions, so always double-check the specifications of your laptop and the power supply.
3. Polarity: Additionally, the polarity of the connector is important. The central pin typically carries positive voltage, while the outer sleeve of the connector is the ground (negative). Reversing polarity can damage your laptop, so make sure the connector is inserted correctly.
4. Safety: Always use the power adapter that came with your laptop or a compatible replacement from a reputable manufacturer. Using an incorrect or incompatible power adapter can not only damage your laptop but also pose safety hazards such as overheating or electrical fires.
5. Replacement: If you need to replace your laptop's power adapter, ensure that the new adapter provides the correct voltage, polarity, and wattage for your laptop model. It's often safer to purchase adapters from the laptop manufacturer or certified third-party suppliers to guarantee compatibility and safety.

Most laptop can be used in any country.
Check the laptop's power adapter mains input voltage, it is on a label on the bottom of the adapter.
If the input voltage is 100 to 240 volts then it will work in Australia, you may need an mains adapter to connect to Australian 3 pin mains power point or purchase the mains cable that fits the Australian 3 pin mains power point.

All whistler models run on 12 volts and the center pin of the power cord is positive.

Here is how you might check the polarity of a 7.5 volt DC replacement adapter:

Put the 5 batteries into the unit and verify operation. NOW using a DC voltmeter measure the voltage from battery negative and meter negative connected and meter positive to the pin on the power jack. IF you see 7.5 volts positive, then the pin is the positive lead for the adapter.

If you see zero, then continue testing.

With the 5 batteries inserted, connect the positive meter lead to the positive of the stack of batteries. Now touch the negative meter lead to the pin.
If there is 7.5 volts there, then the pin is the negative lead for the adapter.

READ THESE INSTRUCTIONS CAREFULLY.

USUALLY the jack has a contact that disconnects the batteery when the plug with sleeve is inserted.. We are testing the jack without inserting a plug here so the plug should HAVE THE BATTERY VOLTAGE with correct polarity on the pin.

A transformer type (Linear Mode Power Supply) AC to DC power adapter with a 9.V nominal output, measures about 12.V without load when tested with a multimeter. A power adapter with a nominal output of 7.5 V, measures a little over 9.V. Considering a number of people across different forums reported the adapter's measured power output as 12.V, I think the nominal rating of the AC to DC adapter should be 9.V. However, keep away from Switch Mode Power Supplies.

Either the ac adapter is defective or the dc connector on the motherboard is bad. I would test the ac adapter with a volt meter and make sure you are getting voltage through first. If there is power then likely the dc jack and someone will have to solder in a new connector

If there is no power/charge lights on, it is likely the power adapter is faulty or the power socket on the laptop is faulty.
To test the power adapter, test the power plug that plugs into the laptop with a multi-meter. The voltage reading should be slightly higher than the voltage that is printed on the label on the bottom of the power adapter. If the voltage reading is zero or below the voltage on the label then the adapter is faulty and needs to be replaced.
If the voltage reading is OK then the power socket on the laptop could be faulty. Connect the adapter to the laptop and wriggle the power plug on the laptop, it the charge LED flashes as you wriggle, the the fault is the power socket, it may simply have a dry solder joint or it is faulty and needs to be replaced. This requires the laptop to be dismantled to fix/solder the power socket or replace the faulty power socket.

power adapter is definitely defective if it only has 7.2 volts on it output. check if you have plugged it in the correct voltage!

As long as the Voltage matches it does not matter where the power originates from. The voltage must match exactly to the adapter readings. Hope this helps.