Reverse-Backward
Reverse-Backward t1_ivi72e3 wrote
Reply to Sound Dampening Panels on Ductwork? by Casked_Away
https://hvac-talk.com/vbb/threads/1763011-Baffle-design-to-reduce-noise-of-return
A baffle in the cold air return will reduce sound transfer up through your air return / wall space.
The closer to your sound source, the better, to reduce sound propagation.
Reverse-Backward t1_ixfaylz wrote
Reply to How can I trigger a string of PWM RGB LEDs using a solid state relay without introducing resistance and significantly dimming the LEDs ? by irreligiosity
Shouldn’t you be able to do this using an interposing relay?
Typically used where low voltage triggers high voltage or vice-versa.
An interposing relay should just have dry contacts that close (or open) when you want to command the control coil to operate. Two different power levels can exist on an interposing relay with no influence on each other. Therefore no dim LED’s once you close in the contacts.
https://control.com/textbook/relay-control-systems/interposing-relays/ Ignore the overly complicated explanation in this linked article, but focus on how they show the DC relay on the PLC side (controlling device) connected to the relay coil which then closes the other circuit to the motor starter (your LED lights)