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Free (Australia) - Chipamp.com LM3875 Rev 3 2 x modules

GONE

I'm giving away 2 Chipamp.com LM3875 modules (the kits came from Peter Daniel in 2019). These are surplus to my needs and do not come with heatsink, power supply etc. The pic of assembled in case for reference only.

I ran these off 27VDC rails (10000uF per rail) and had a shorted DC offset of 5.5mV, -12.8mV (unshorted < 100mV). For the supply I was using, 34W into 8R and 50W into 4R and needs a heatsink better than 1C/W.

These are unusual with their grounding as the chassis ground back to the chassis earth is take from the amp boards and not the power supply. Get it wrong and they can hum but silent when correct.

I'll supply the Chipamp.com Rev 3 board details from Brian Bell and Peter Daniel has an amp build guide at AudioSector. The caps are Nichicon KZ by-passed with X7R monolythic and a zobel is used.

All wiring is via connectors and from left to right: +ve, not used, chassis ground, power ground, -ve. Signal in is via Oupiin 3 way terminals and speaker via 2 way plug in terminal.

I will cover postage and this offer is for Australia only.
 

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