Ts4d Motorola

[dieseljeep]

Originally Posted by timmy

Well the issue of the audio hum has not been found so I am done with looking for it so instead I placed 2 - 6.3v 680uf in parallel across the speaker leads so when with the volume was down the hum was very noticeable, loud, now the hum cannot be heard when the volume is down and still have good volume.

How did you determine that value, mathematically?
It sounds like a plan!
Your hum problem was a topic of discussion between myself and another VK member at the WARCI swap meet.

[timmy]

Originally Posted by dieseljeep

How did you determine that value, mathematically?
It sounds like a plan!
Your hum problem was a topic of discussion between myself and another VK member at the WARCI swap meet.

Well no math as I'm not good In math so I just found that the lower the rated voltage of the cap and the highest in uf worked best, I guess you can say it was Alittle trial and error. I found that my other motorolas has the same hum but very low and have to get up to the speaker to here it so after putting those caps across the speaker leads it seems to filter out 90% of the hum and at the same time added Alittle bass to the sound, kind of warmer sound since befor I put the caps in the sound was ok but had lots of treble. The lowest voltage caps I had was 6.3v maybe lower would have been better , maybe even a non polar cap could have been better but I only had higher voltage non polar caps so that was out. It didn't matter about polarity since sound is mostly ac. So the topic of the hum you had, any conclusions?