The story of my aquisition of the Siera TR-5842 (Aiwa CS-600 in disguise)

It is definitely worth checking the value of the fusible resistor. I have been fixing a Sony turntable that uses two fusible resistors in the arm motor drive circuit.
One was completely open circuit while the other was twice the expected value of 68ohms. As I couldn't get the correct wattage
I fitted higher wattage resistors in series with PolyFuses. These have the advantage that they will reset themselves if you let them
completely cool down.

It is also worth checking that there is nothing sticking or fouling in your mechanism. Does it move freely by hand ?

 

Well there's some initial resistance when the heads are raised as this is driven by the motor. But then when the tape is playing it's only the flywheel and the the takeup reel. And yes they run freely but the motor can't pull them to the correct speed.

 

Then the brush's in the motor are worn and cannot deliver enough current to the armature to rotate with enough strength, so you need a strong or newer motor.

 

James as Cassette2go in youtube
Aiwa CS-600 Boombox cassette plays but Why no power from mainboard? (25:48) minutes

Cassette2go as James in facebook
Aiwa CS-600 cassette plays but, why does the cassette deck motor not have power from the main board I don't know

December 2023 (28:04) minutes

https://www.facebook.com/video.php?v=1555213545220104

https://www.facebook.com/video.php?v=1555213545220104