Help needed: Best practice for checking audio IC functionality

I am currently restoring a vintage AIWA HS PX-410. I've done a full cleaning and recap. I have found that the power section is working fine: RWD/FWD works nicely. However, the PLAY button is non-function and if I bridge the appropriate internal switch, the play mechanism is working and the hubs are turning, but the phones output is dead.

I suspect either a fault in the power supply to the main IC (TOSHIBA TA8115F) or the main IC.



Could anyone direct me to a good guide on how to check said IC for functionality with a multimeter?

Many thanks!

 

Hi,

Here’s a datasheet https://datasheet.datasheetarchive.com/originals/distributors/Datasheets-39/DSA-764450.pdf
But I do not think you can measure a lot with a multimeter. Maybe check Vss on pin 13 at least you can tell if it has power. The voltage should be within the range from 1.5 to 6V when you measure between pin13 and pin1.

I would use a oscilloscope to measure the audio switch and amplifiers. Not sure if this can be done with a multimeter. But I am not a professional.

Good luck

 

Thanks Daniela, that was very helpful! I knew of the data sheet, but your practical hints were what I needed.

Unfortunately, I have in the meantime found that at least one problem seems to be related to a lifted pad on the PCB. While probably reparable, I'll likely not go that way for the moment as this PX410 may serve me well as a spares machine anyway. The good one is in perfect order.