Interesting piece of effect came to my hands to make slight modifications to it.
This one was produced only for short period in early 80’s. The problem is that it can only be powered with 9 volts battery, but not with power supply. Drilling a 12mm hole for new DC power jack is out of question, as these are becoming to be valuable, and permanent modifications would have negative impact to its value. Instead, I ended up to drill a small 3mm hole to the bottom plate, and connect a adapter straight to existing battery clip.
Note the circuit covering plastic shield. There is ”Maxon” printed to it. Maxon designed and manufactured many models for Ibanez, including TS808 and TS9, FL9 Flanger, CS9 Chorus, and AD9 Analog Delay. PT-909 also exist with different bottom plate and DC jack included:
Note the ”Maxon” text again inside the battery compartment cover. I don’t know why two different configurations exist, but this one is now happily running with power supply with only small invisible modification in the bottom of the chassis: