I recently bought a beomaster5500, a beogramCD50, a beocord5500 [this item will soon be arriving from Lee] and a mcp5500; the exteriour is in reasonable good condition, technically they are in perfect shape, except for the mcp5500.

The wheel which adjust the volume is moving too easely, the volumelight on the mcp nor the volume itself on the master is reacting, I've bought a spare mcp5500 for a few euro's beacause the exterior in a lousy condition, but in good working order.

I've opened the both of them, but I can't figure out what and how the wheel is activating things [a belt, a current or what?] so I might be able to solve the problem, otherwise I will detach the content of the ugly [but good working] mcp end put it in the beter looking one [if that can be done easely]

It looked like an easy fix but it's not [for me anyway]

Does anyone has a clue or a suggestion?

The Volume wheel switches a little cherry-switch in both directions, for volume up and volume down.

Did it work?

Ulf

Hi Leon,

             I've posted a reply to this question as asked in the vintage products section.

Chris.

There is a micro switch mounted on the inside of the wheel. Depending which way you move the wheel the switch either makes contact one way or the other. (Easy to see, not so easy to explain)

The contacts of the switch become dirty and no longer make contact. I clean them with fine emery paper and this usually gets them going.

BEWARE THE SMALL SPRING ON THE SWITCH. IT CAN PING OFF AND GET LOST!!!

The switches merely tells the electronics whether to turn up or down.
The step pulses comes from the opto reading the black and white square pattern through a tiny hole on the side of the casing surrounding the
volume wheel on the inside of the Master Control Panel.
The opto is a single 3-pin unit with both transmitter and
reader in one, mounted on the PCB, obviously very close to the volume wheel.
I've replaced the opto in a couple of MCP's recently where the
transmitter section had become weak.
(New opto's are in stock).

Symptoms (if I remember correctly) are that when the volume wheel
is turned, the MCP lights up as supposed to but doesn't change the volume.
The Beomaster doesn't react since no information is sent from the MCP.

If the switch is bad, I believe you won't get any reaction from the MCP at all when the wheel is spun but since I haven't seen this fault, I am not 100% sure of this.

Martin

thnx for all the reactions; I will try to find the cherry [switch] and see what I can do for myself about it.

compare the both of them and see what the difference is between the working and not working wheel.

keep you posted...........I'll keep my fingers crossed and my eyes open.....:-)

Let me know if you need a replacement switch - I have a spare sitting around doing nothing

Chris.