Hi!

I am renovating my Firepower sound board.
It was working cca 2 years before i put the board to the shelf as a spare.
I have decided yesterday to change all capacitors and test it.

The board producting this strange noise only:

Do you have an idea what could be wrong?

(The eprom and the voltages are)
I have tried with another speech board the result was the same.

You mean the quartz crystal for the CPU?
I did it but it did not helped.
I also reflowed the connectors...

Hi!
The board was working but I have not tested before recapped it most probably it get broken before I did it.
I have not checked with a logic tester but it must be running becouse it switching the sound
just playing them badly.
The eprom is good, CPU is good, quatz is good.
(I have tried it with brand new CPU)
I think when the CPU is bad then nothing happens...

I was working on the board and had replaced couple of components :

6821 PIA and socket
Eprom socket
MC1408 DA converter
Quartz crystal Y1
Reflowed the amplifier

(The eprom is good)
CPU is good but i have not replaced its socket yet.

Unfortunatly the error is still there.
Interestingly after i replaced the 6821 the sound started to working normaly then it went to the bad state again.

CPU and PIA is running i have checked them with the LEON test eprom!

I have replaced the 6810 RAM that was the bad part.
I should have started with LEON especially the memory test!