SammichFM ...no sound

[kogz23]

Hi there,

I'm building a MBFM using a sammichFM base board.

Voltage tests passed and have discovered no shorts...as of yet!

The firmware is running fine.

However I'm getting no sound at all. I'm thinking the problem may be that the 14.31 crystal I am using is one pulled from an old Commodore 64. It has 2 legs with a 3rd ground leg. Looking at the board I'm seeing only 3 of the 4 possible pads are being used. However I think what I'm using is a crystal rather than an oscillator.

Is this probably my mistake?

Thanks in advance

Al

[Wilba]

The sammichFM base PCB (and MIDIbox OPL3 module) require a crystal oscillator, not just a crystal. A crystal oscillator actually outputs a clock signal (it has semiconductors inside), whereas a crystal is used in conjunction with other parts to generate a clock signal.

I don't know what part you are using, and even if it is the right part, desoldering it from a C64 could have damaged it, just like desoldering any IC or transistor can damage it. I recommend you get the right part. For reference, it is Mouser part 815-ACH-14.31818EK