DIY battery powered phono preamp. Battery management circuit as in <a href="//commons.wikimedia.org/wiki/File:Battery-powered_preamp_-_power_management_(UVLO,_muting_delay).png" title="File:Battery-powered preamp - power management (UVLO, muting delay).png">File:Battery-powered preamp - power management (UVLO, muting delay).png</a>. BMS board mounted under the perfboard. The left relay connects the battery to the load, the right relay mutes the output on transients. The opamp on the right is a precision average rectifier for driving the VU meter. Sweet bells and whistles.
<a href="//commons.wikimedia.org/w/index.php?title=User:Retired_electrician&amp;action=edit&amp;redlink=1" class="new" title="User:Retired electrician (page does not exist)">Retired electrician</a>
2021-12-21 11:35:31
<span class="int-own-work" lang="en">Own work</span>