Anthem MCA 20 - Powers on but no sound

lobes

Member
2015-04-22 10:13 pm
Hello all,

I've had an Anthem MCA 20 Amp that hasn't worked for quite a while. Nothing ever "happened"(no pop, bang, drop, ect..), just one day after not using it for quite some time, it stopped working. I'm a novice for sure when it comes to doing these types of repairs, but I'm not planning on taking it to have it serviced, so I'm hoping someone could possibly point me in the right direction. I'll do my best to supply all the information that I can that may help, but if you need anything else, please ask.


- It powers on, but doesn't output any sound.

- I've checked the fuses(The main fuse, and two inside the case-I think that's all of them), and they all appear to be good.

- I don't see or smell any burns.

- I don't see any bulging or leaking capacitors.

- I hear a click(relay clicking I guess?) immediately after turning the amp off, but not when turning the amp on. However, if I leave the amp on, then plug the power cord in, it does click. (I'm not sure if this has any significance).

- The LED is green when it's powered on, no LED when powered off. In Auto mode it stays green, instead of turning to red as it's supposed to(it should turn to green only when receiving a signal in this mode).

- Leaving the amp on for hours(or more) seems to produce no heat from the case, or out of the case vents.



Anthem MCA 20; Anthem | MCA 20 | Overview


Manual; http://www.anthemav.com/downloads/MCA_Manual.pdf


Photos:

https://i.gyazo.com/cc60086965bedcbfc6f5d5385b1ad2b3.jpg

https://i.gyazo.com/9d3f7e868f08fed7a14d4f5f6e953df4.jpg

https://i.gyazo.com/b47693b3c150b1f9b1324891ba4cdf22.jpg

https://i.gyazo.com/8262d5b32ee04428791f00031a82c36d.jpg




Even if you could just point me in the right direction or give me an idea of what's going on here, it would be greatly appreciated.

Thank you for your time,

Joe
 
Hey Joe. How did you make out with your amp? Picked up a MCA5 with the same problem. Going to check the auto on power feature for starters.

Sorry for reviving a dead thread but....

I have a MCA5 with the same problem I picked up yesterday. The previous owner is offering to take it back. I'm into it so little money if its and easy fix I'll do so. Thoughts?

3 out of the 5 channels work (FL, FR, C), but no sound out of the 2 rears.
 

PeterMeni

Member
2010-01-13 8:28 pm
I have the same problem with an MCA-5. I upgrade the power supply of the two main channels by adding two more transformers 450 VA, 50 amps bridges and a 88000 mf capacitance on each channel. I connect the center channel to the old Left-Right power supply. After that each channel works fine when i measure at the circuit output but the output protection relays don't connect the circuit to the connectors. I am looking for the protection circuit diagram or any idea for the problem. Thanks a lot.