Spring Reverb disconnected?

[dillweed4]

I have a Vox Venue Lead 100 amp, the reverbs not been working for a while so I decided to open her up and have a look inside. Someone has disconnected the reverb, but everything else works OK I think. If anyone can help that'd be great, I have a few pics and a schematic that should help:

[IMG]******//www.voxamps.com/downloads/circuits/vlead100.jpg[/IMG]

What are the purple wires connected to and why is there a loose green wire?

[IMG]******//img204.imageshack.us/img204/9430/dsc0052bu.jpg[/IMG]

These wires come from the power source behind the reverb, I don't know what the loose purple wire is for though?

[IMG]******//i39.tinypic.com/2uyljyp.jpg[/IMG]

And what about these loose wires? Do you think they should go to the reverb?

[IMG]******//i43.tinypic.com/14wg39e.jpg[/IMG]

This bit of the circuit has been sabotaged as well:

[IMG]******//i39.tinypic.com/iqwolh.jpg[/IMG]

Any help to sort this and get this fantastic old amp running right again would be greatly appreciated!

[LeeYoo]

Hi dillweed4.
Going from the joiner blocks, I would say that the previous owner has used a different, or external reverb with the amp.
Start reconnecting those wires to the reverb coils with new shielded wire.
Maybe you can measure the resistance of the coils.
My guess is that the coil with the thin wires is the return.
From memory, send coils will have a lower resistance.
This one connects to the 741 chip.
Maybe someone with the same amp could take some pictures.
Leo..

[dillweed4]

Originally Posted by LeeYoo

Hi dillweed4.
Going from the joiner blocks, I would say that the previous owner has used a different, or external reverb with the amp.
Start reconnecting those wires to the reverb coils with new shielded wire.
Maybe you can measure the resistance of the coils.
My guess is that the coil with the thin wires is the return.
From memory, the send coil will have a lower resistance.
This one connects to the 741 chip.
Maybe someone with the same amp could take some pictures.
Leo..

What do you mean by 'joiner blocks' ? Also both sides of the reverb tank have thin wires, only one end has an extra green wire that you can see in one of the pictures. I wish I knew how to read a schematic better, my electronics skills are not quite there yet.... thanks for the help though man

[LeeYoo]

Haha, joiner blocks are those plastic lego blocks.
To fix this amp, you have to be able to solder some things. Or seek help from a friend.
Someone has cut the wires between the circuit board and the reverb tank, and has put joiner blocks on the cut wires. Maybe to use a different tank.
You will have to replace those shielded wires. Buy new, or butcher/split an old RCA lead.
A reverb tank has two sets of wires.
One that drives the tank. This comes from the 741chip. The longest wire in your picture.
And one that picks up the reverb sound from the springs. The return.
The question is which tank coil is the drive, and which is the return.
My guess is that the side with the green wire was the return.
To be sure, you have to measure DC resistance.
The green wire is just a ground wire. Don't know why this was cut.
It might have been connected to the ground lug between the two purple wires.
The brown stuff on the circuit board is just solder resin.
Can't see on the picture if the copper track under it has been cut or not.
If unsure, clean a small area with a Q-tip and acetone (nail polish remover).
Leo..

Some reading material: Spring Reverb and ::::::::: Accu Bell Sound Inc :::::::::
The last site shows that the drive coil has U-shaped iron, and the pickup coil has W-shaped iron.

[dillweed4]

Originally Posted by LeeYoo

Haha, joiner blocks are those plastic lego blocks.
To fix this amp, you have to be able to solder some things. Or seek help from a friend.
Someone has cut the wires between the circuit board and the reverb tank, and has put joiner blocks on the cut wires. Maybe to use a different tank.
You will have to replace those shielded wires. Buy new, or butcher/split an old RCA lead.
A reverb tank has two sets of wires.
One that drives the tank. This comes from the 741chip. The longest wire in your picture.
And one that picks up the reverb sound from the springs. The return.
The question is which tank coil is the drive, and which is the return.
My guess is that the side with the green wire was the return.
To be sure, you have to measure DC resistance.
The green wire is just a ground wire. Don't know why this was cut.
It might have been connected to the ground lug between the two purple wires.
The brown stuff on the circuit board is just solder resin.
Can't see on the picture if the copper track under it has been cut or not.
If unsure, clean a small area with a Q-tip and acetone (nail polish remover).
Leo..

Some reading material: Spring Reverb and ::::::::: Accu Bell Sound Inc :::::::::
The last site shows that the drive coil has U-shaped iron, and the pickup coil has W-shaped iron.

Sweet, this is very helpful- thanks. I will try to think this over and sort it out.... I am handy with a soldering iron luckily so I should be able to achieve something! If I do I will post the result.