Radio, CD player and tape power supply .

[Mike678]

My player runs on 240 volt a/c or 9 volt d.c . They are c size . Using the radio does not use much power but playing cd's or tapes , the batteries do not last long . I have coverted it to 12 volt d.c. Bought a step down transformer , 12 to 9 volt d.c. Cost $9.60 . Now I can connect to any 12volt d.c. supply .

 

[XLOOX]

Perfect, as long as you have ensured the power rating is about double what the power draw is.

I have had a couple of ebay buck converters like that let the magic smoke out at under their rating, but with sufficient overrating you will be fine.

 

[Nightjar]

Step down or step up power, looks like you have found one that works for you.
Have laptop set up in my ute, have a step up 12V/19V to keep it charged.