Hello everyone,
due to Covid I have too much spare time, so I decided to do a project: give my old NAD 216 poweramp a new enclosure.
Electrically, I didn't make any changes. I only de-soldered the signal wires to the power amps, and removed the (audio) inputs from the power supply board because with the new enclosure these will be relocated.
Before mounting it all in the new enclosure I remade all connections and turned the amp on. After 3 seconds it switched itself back off. So, the protection circuit has been activated.
There are 3 (groups of) connections between the power supply board -which also houses mute, protection etc- and the left and right power amps: a 7 pin power connector, amplifier output (4 wires) and a signal input connector (signal and ground).
After some testing, this is what I found out: with both power and amp-out connected there's no problem. With 1 of the 2 inputs connected, no problem. As soon as I connect the second input to the power amp the protection gets activated and the amp shuts down.
Just for the heck I tried something else: connected the left input to the right channel power amp and right to left. To my surprise it stays on this way. If anybody has any ideas about this...please share.
Meanwhile I will put the amp back together and hook it up to a source and some speakers, see if it actually plays music.
due to Covid I have too much spare time, so I decided to do a project: give my old NAD 216 poweramp a new enclosure.
Electrically, I didn't make any changes. I only de-soldered the signal wires to the power amps, and removed the (audio) inputs from the power supply board because with the new enclosure these will be relocated.
Before mounting it all in the new enclosure I remade all connections and turned the amp on. After 3 seconds it switched itself back off. So, the protection circuit has been activated.
There are 3 (groups of) connections between the power supply board -which also houses mute, protection etc- and the left and right power amps: a 7 pin power connector, amplifier output (4 wires) and a signal input connector (signal and ground).
After some testing, this is what I found out: with both power and amp-out connected there's no problem. With 1 of the 2 inputs connected, no problem. As soon as I connect the second input to the power amp the protection gets activated and the amp shuts down.
Just for the heck I tried something else: connected the left input to the right channel power amp and right to left. To my surprise it stays on this way. If anybody has any ideas about this...please share.
Meanwhile I will put the amp back together and hook it up to a source and some speakers, see if it actually plays music.