Current Draw of an old Sony Handycam?

[polishdude20]

Hello!

I've got an old Sony TR200 Handycam and lots of Hi8 tapes of family memories! I've lost the charger long ago and the batteries are dead. I know I can buy a charger+ batteries on ebay for around $30 but I want to build my own power supply that can provide the 7.2 volts the camera needs.

The problem is that I don't know the current requirements a camera like that would need. I've made a simple LM317 circuit to provide 7.2 volts but the max current the LM317 can provide is 1.5amps. When I turned it on, the little LCD screen kept turning on and off and it was clicking probably due to the inside motors being engaged and failing because they couldn't get enough current!

So does anyone know how much current this puppy needs to operate?

[Richard Crowley]

If it isn't specified on the nameplate or in the user manual, you could power it from a bench supply and actually measure it.  For that matter you could simply power it from the bench supply until you get all the tapes captured/copied.  If nothing else, I would assume I need 5A.  If it still doesn't work, then it is broke.

It is possible that 1.5A is insufficient because some mechanical part/bearing is frozen and it is drawing more than its normal design current.

There are plenty of simple circuits that will boost the current capacity of a 3-terminal regulator with a bitter pass transistor and a few resistors.

It isn't particularly clear to me why it would be worth building a dedicated power supply for it?

[What_NZ]

Where are you trying to input the power?
If it is where the battery connects to, then you will need 7.2V and more than 1.5A.
If you are connecting to the DC input jack it is 6.5V @ ~1.8A
Most camcorders cycle the mechanism during power on so initial peak current will be higher. Maybe a large capacitor will help with the peak current.