This is a follow up to my recent post about the redesigned Beogram Commander remote control board, which now works in both (DC-motor) Beogr...
Saturday, August 30, 2014
Beomaster 8000: Replacement of Speaker Switches - Laser Cut Plexiglass Switch Adapters
I always replace the speaker switches when I restore a Beomaster 8000. They are often corroded, and I experienced several failures in my own Beomasters (I often use my Sennheiser RS180s, and therefore need to switch the speakers on and off fairly frequently...). The issue with these switches is that the original model was designed with a high density board base, which had installation guide tabs on the side. The Beomaster housing is designed with bays that fit these tabs exactly. All new switches seem to be fully enclosed in plastic. While the general form factor is still available, in the past I had to extract the high density boards from the old switches, modify them with a Dremel, and then glue them to the bottom of the new switches. See this post for the original procedure:
I never really liked the Dremel job...not precise enough for my taste. Recently, I learned to operate a laser cutter. What better first project than designing a nice adapter plate, which would align the new switches precisely to their compartments??
I cut the adapter platelets from 5/64 plexiglass (this is a bit too thick, but that is all I had at that point). That meant I still had to put the Dremel to them to reduce the thickness of the tab areas to about 3/64, the thickness of the high density board. If I do it again, I will cut the entire adapter board from 3/64 plexi or something similar. This shows the new switches in comparison with one of the old ones and the laser cut adapters. Note the slits, the board mounting guides of the switches fit snugly into them, aligning the switch (BTW: I used No.: 611-S201031MS02Q from Mouser) with the adapters.
Here after glueing the adapters to the switches and Dremeling the tabs thinner:
Here are a few pictures from the installation process:
Original switches removed from their compartments for desoldering:
New switches installed (it surprised me how durable the plexiglass was during soldering...no issues with melting, warping etc...):
In their compartments:
And with heat sink cover installed:
Perfect!! These new switches are much smoother than the old ones and are guaranteed for a few million switchings! On to the display board!