Did it this time...

[ampman]

Hi everyone,
I am as careful as one can be with equipment and rarely ever damage a piece. As luck would have it most times nothing major happens. Thankfully, I "get away" with minor scuffs or nothing at all.

Yesterday, I dropped an 100W Onkyo power amp. An A-RV401.

It was working, now it isn't.

Thankfully, this happened to my equipment.

The amp was working just before I took it out of the system. My intent was to verify voltages and operation.

It fell onto the transformer end flat. No bounce or other signs of torque. Absolutely flat.

Nothing is bent or askew on the chassis and I do not see anything broken or otherwise damaged on the circuit boards or components.

The display is not working, the inputs are not passing sound, but the biggest issue is the relay does not click-in as expected.

I started checking from AC in and discovered:
- the AC into/out of the transformer is withing spec.
- the B1+ voltage is good to the electro caps
- the voltage out of the caps is good.
- I have the service manual and have spot checked other voltages with all appearing to be within spec.

Protect is happening instantly I suspect.
How does the protect circuit work? Where should I start looking for problems?



Thanks in advance.

 

[Roypercy]

Don’t know if this helps, but I dropped a very heavy Yamaha home theater receiver bringing it in from my car. No real damage to the case except for a nasty scuff, but opening it up I found that a couple of ribbon cables had popped loose from their connections. I reattached them and it worked perfectly.

 

[slovell]

Maybe the shock kicked a fuse out?

 

[Bradbrews]

I fixed up a Sony SACD player that was dropped. The impact had caused the display glass to shift and tear multiple connections off a circuit board. It also bent a few mounting screws and the attached parts.
Look for physical damage. You’re bound to find some.

 

[heyraz]

I would look for cracked solder joints.

I'd look around a heavy component (transformer) and areas that could be potentially stressed during a fall.

 

[ampman]

Hi everyone,

Thanks for the thoughts and advice.