Verify the power supply voltages and filtering.Refresh all circuit board solder joints (flow-soldered joints also have only about a 30 year lifespan).Replace all electrolytic capacitors (they have only a 20-30 year lifespan). Rotate all tape guides (necessary, since they also develop wear grooves from the tape passing over them).Re-lap the heads (an absolute necessity if you are going to change how the heads are aligned at all, since they normally have significant wear grooves in them).Clean and de-oxidize all user controls and internal switches/contacts (most units have dirty controls).Adjust reel torques (braking, take-up, back, FF and REW).Completely disassemble, clean, lube and adjust the transport mechanism (a real contributing operation to sonic performance, like wow and flutter).Rebuild the tension rollers (they all need to be cleaned, lubed, and fresh damping fluid added), and replace the tape sensor micro-switches (they all are somewhat corroded at this age).Replace the felt brake pads (felt brake pads that are almost 30 years old probably have dried out adhesive, and may appear to work, but we are shooting for another 20-30 years of use here).Replace the capstan drive belt, available here:.Rollers can be re-rubbered by Terry Witt ( ) at a reasonable cost. Replace both pinch rollers (for some reason, all RT-909 original pinch rollers are gooey/gummy at this age), and adjust the pinch roller pressure.Perform a complete initial functional test, to determine if there are any repair operations need to be performed before restoration, and to provide a baseline for comparison with post-restoration performance.Here is an overall list of operations I perform on these units, before offering them for sale (in my opinion, none are optional): After almost 30 years all of these will need some restoration operations performed on them, even if they appear to "work." They may work, but you will never know what they can "do" until you bring them back up to full steam. This thread is for those who have had an RT-909 since they bought it new, or discovered Dad's RT-909 in the closet, and want it to perform up to, or exceeding, original factory specs. It is no wonder that so many of these units were sold back in the day, even as expensive as they were ($1100 1979 dollars). My main rig will never be without a one of these beauties. The unit I just restored has playback response of 20-20Khz +/- 0.5db, at -10db modulation, which blew me away when I heard it put all together. The design is truly simple, yet elegant, doing away with most of the complicated mechanism of many of the other decks in its league. It is rack-mountable, handles 10.5" reels, is a dual-capstan, closed-loop servo controlled drive, electro-motive reel braking, with auto-reverse capability. The RT-909 is by far the nicest consumer reel-to-reel Pioneer ever produced.
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