Egnator Armageddon Amp (damn nice actually)

Anyone familiar with these things ?

I got intermittent not switching channels.

In channel 1 it is fine. It does not go into channel 2. It indicates that it has gone into channel 3 but does not, actually the audio is still going through channel one. (at all times)

I seems to use relays and that is where I am headed. I don't even know what to quote the guy, this is one of the not better R & Rs out there. I'll also need a whole bag of wire ties to put it back together.

Anyway, it must be a connection because so lovely it will not do it when the chassis is upside down. Which is when you can see it. And it not doing it when on for a while. When it was first started up for the day I oculd kick the chassis around a bit and get it to do it. After while, no more.

And this thing has lead free solder.

I wonder if anyone knows where the micro is in this, as it would ocntrol the channel switching, right ?

In testing, I unpluggerd the footswitch to see what happened. this was after it started working and it defaulted to channel one when plugged in hot. Even if it was not in channel one it would be when you plugged that in. Then it would switch fine when working. It just initialized thar way.

this thing might not even have a micro for that. A ring counter would do it.

So, anyone know how these people diesign tings or have a resource ?

TIA

I had a similar problem recently with a 3 channel Hughes and Ketner. I couldn't get schematics to find out why it wasn't switching channels. And it had a microcontroller in it and MIDI and stuff.

There were loads of relays doing the switching, so I just looked at the relay coil that wasn't audibly switching. It had 24v on both ends, so it was probably meant to switch via a transistor shorting one end to ground. A quick ground with a flying lead confirmed it. It was a pretty simple case of following this path to ground though several ribbon cables via 3 PCB's until I established one ribbon cable connection was open.

Nothing to do with the micro thank god.

Gareth.

The way this one acts I would say the processor is OK. It has MIDI so it has one I guess.

I think I am looking at a connection on the board because it does it cold and I can't get it to do it upside down. I guess what I am lookng for is i someone knows where the switching voltage originate.

The big board with the pots and switches, and relays, is gonna be a whole lotta fun to take out. I see another board on top of it, it would be nice to find the problem on that but I'm not holding my breath.

Nowhere do I see any chip looks like it could be a microprocessor. Maybe it is a SMD on the bottom.