The Basics when Looking for an HP 239704-001 Adapter.

1) Output Specs Voltage and milli-Amps

2) Regulated /Un-Regulate

3) Connector plug size/Output Polarity

1) Output Voltage and milli-Amps

Try and Find your specifications for your HP 239704-001 Adapter. On the old adapter, Device wishing to supply or specification page in an owners manual. The specs are usually given as volts and milliAmps (mA). Always try and find a exact match of specs. This is the safest way to go. Where an exact match is not available a couple general rules of thumb to find a workable adapter.

Choose the closest voltage available . Safer to go lower the higher. Some devices can handle higher without damage but many will not take it. If you choose lower generally the worse that would happen is it would not supply adequate voltage and equipment would not normally be damaged.

Choose milliAmps equal or higher than required

2) Regulated (Switching) or Unregulated (non-switching) Output

Most AC adapters are unregulated, Voltage output of the power supply floats with the load placed on them. Some electronic equipment such as digital cameras or security cameras are very sensitive to the input voltage and so require a Regulated/Switching adapter.  A regulated AC adapter guarantees that the output voltage will always be constant.

Do Not use an unregulated supply in place of a regulated one!

Ok to use a regulated (however generally pricer) in place of an unregulated.

3) Output plug size/ Output Polarity

These are measured in mm. I will try and give these measurements as accurately as I can. If the plug is not correct for your application. Radio shack or another supplier may have an adapter or the existing plug can be spliced to the replacement adapter if you be sure to check polarity before attaching to the equipment.

Output Polarity

Adapters with an AC out put this is not an issue however ANY and ALL DC adapters it must be observed or equipment damage most likely will occur.

 To determine the polarity of your HP 239704-001 Adapter look for a symbol like this: I will have the same symbol on my auction pages for adapters.

Babatek.com, a reliable US computer parts online company, is located in Santa Clara, CA, which maintains a complete inventory of brand new HP 239704-001 Adapter.