When ordering belts or taking a peek inside there are usually several different belts.
This is a Sony TC-399 that's similar to model: TC-366, TC-377, TC-378 and TC-388.
(1)are the counterbelts, one long from the counter pulley up to the second pulley located next to the L- reel-table. Another shorter belt is then attached behind the reel-table from that pulley. (2)Drive-belt is attached from capstan-motor pulley to the left idler-wheel. When engaged on rewind the idler-wheel goes against L-reel-table and start rewinding. (3)Help-belt is the longest that goes around from a small pulley on the fly-wheel to a pulley behind the R reel-table. Function of this belt is feeding the tape to the right reel on play-mode. This belt is difficult too replace, because the whole mounting plate where the head-assembly is attached needs to come off. See picture below:
Sony TC-366 with the mounting plate and fly-wheel off.
(1) Left Idler-wheel. (2) Right Idler-wheel. (3) Pulley attached on the capstan-motor. (4) Flywheel. (5) Pinchroller.
(1) Automatic shut-off switch that engage the capstanmotor to stop when tape is ending. Sometimes this switch goes bad. (2) Erase-head. (3) Record head. (4) Playback head. The red arrows are tape-guides that also is important to keep clean, otherwise severe tape-flutter, damaged tape, slow speed on play, or sluggish rewind/fforward can be the result.
Similar models: Akai GX-4000D, 4000, 4000DS X-150, 1700, 1710, M-series. (1)Automatic-shutoff switch. When the small arm is lifted up treading the tape it's engaged with a small rod to the switch and sending voltage to the power-supply for the capstan-motor. This model has one-single motor and several idler-wheels. (2)Idler-pulley. When rewind is engaged the idler-wheel goes against this pulley. (3)Idler-wheel. For rewind function that goes against capstan-pulley + plastic idler-pulley. (4)Capstan-motor with attached pulley. (5)Idler-wheel for fast forward function and play-mode. (6)Tension-roller made of plastic (7)Track-selector switch that moves the headstack up and down depending which track is used. (8)Capstan-axel coming up from the fly-wheel and spin at certain speed from the drive-belt underneath. (9)Cam for play-function. (10)Cam for fforward-funtion. (11)Pause assembly.
(1)Drive-belt. Flat belt that goes around the fly-wheel and capstan-motor pulley. (2)Counter-belt. (3)Capstan-motor. (4)Fly-wheel. (5)Bracket for the fly-wheel and adjusting screw in the center. (6)Linkage for record-switch, this engage the record-switch located on the pc-board below. (7)Start capacitor for the capstan-motor. These need replacement sometimes on many Sony and Akai models. (8) Transformer.
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I have many used parts in stock for different brands and models.
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