Can I use a 9v transformer with this model
What's the make and Model of the device you're inquiring about?
aiwa HS T-200 AM-FM STereo radio cassette
How many AA batteries does the unit take?
This unit requires a 3 volt DC Power Supply adaptor to operate it. A 9 volt will blow the unit very quickly.
Over 20 years of experience installing, troubleshooting and customizing electronics.