Gate Bus Strap Connection Procedure
This is where the rubber hits the road in making sure you have your orientation straight
on the SPDT ON-OFF-ON switches. There are two gate bus common connections – Bus
1 is the signal that sends the gate signals to, surprisingly enough, Gate Bus 1, and Bus 3
is the signal that sends the gate signals to, well, Bus 3. Gate Bus 2, incidentally, is
derived logically from connections to the middle lug of each of the gate bus switches.
But, right now, we’re concerned with only the two outside lugs; we’re going to leave the
center lugs along for the time being.
In this procedure, the illustrations assume that, when looking at the switches from the
actual front of the front panel, the switch levers pointing
up
will direct the signals to Gate
Bus 1 and pointing
down
will direct the signals to Gate Bus 3. That means, from the rear
of the panel, looking at the switch lugs, the bottom row of lugs will be the Bus 1 line and
the top row of switches will be the Bus 3 line (remember, generally up is down on the
rear of a toggle switch). If your legend on the panel is reversed (you want to point down
for Gate Bus 1) be sure to take this into account! Also, be sure your toggle switches
work as described here. If you’re not sure, re-read the beginning sections of this
procedure.
o
Common Connections to the Gate Bus Switches
Connect all of the top lugs of the switches together. After that, connect all of the
bottom lugs of the switches together. As stressed before, it’s stressed again – don’t
overheat those switches and make them go all simple on you – get in there, solder the
wire on and get out!
SW32
Stage 16
SPDT
ON-OFF-ON
SW31
Stage 15
SPDT
ON-OFF-ON
SW30
Stage 14
SPDT
ON-OFF-ON
SW29
Stage 13
SPDT
ON-OFF-ON
SW28
Stage 12
SPDT
ON-OFF-ON
SW27
Stage 11
SPDT
ON-OFF-ON
SW26
Stage 10
SPDT
ON-OFF-ON
SW25
Stage 9
SPDT
ON-OFF-ON
SW24
Stage 8
SPDT
ON-OFF-ON
SW23
Stage 7
SPDT
ON-OFF-ON
SW22
Stage 6
SPDT
ON-OFF-ON
SW21
Stage 5
SPDT
ON-OFF-ON
SW20
Stage 4
SPDT
ON-OFF-ON
SW19
Stage 3
SPDT
ON-OFF-ON
SW18
Stage 2
SPDT
ON-OFF-ON
SW17
Stage 1
SPDT
ON-OFF-ON
Bus 1
Bus 3
Figure 4-8: Strap Wired Gate Bus Switches – Switch Up Selects Gate Bus 1
It’s a good idea to mark on the rear of the panel, which gate bus line is which. That
will come in handy for later reference once you’re ready to hook up to the PCBs.
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