AI6YR Ben<p>This is certainly the circuit used, except instead of variable resistors they have undoubtely selected whatever 100, 75%, 50%, 25% on a SLA would be. (assuming this was originally an SLA battery in here). <a href="https://m.ai6yr.org/tags/schematics" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>schematics</span></a></p>