TT MIDI-Switcher - Version 2019
Input Z1 is designed as "store" to permanently assign the current switching states to a
MIDI program.
The output Z2 is intended for a LED, which signals the successful storage by briefly
flashing.
Power-supply
On the main pcb of the TT-Midi-Switcher are two power supplies available. The main power
supply is essential for the operation of the module, from an input voltage of 6.3 - 9 VAC or
VDC, it supplies the voltage of 5 VDC required for the module. The TT Midi Switcher is
designed for use with 5V relays or optocouplers in the basic configuration.
Important: before using the TT-Midi-Switcher, the total power consumption of the
switching elements must be determined and it must be ensured it does not exceed the
maximum current of 1,5 A the used 7805 can deliver. For higher current and / or different
voltages, the additional power supply must be used. It may also be necessary to passively
cool the 7805 with a heat sink.
The second power supply on the main board, labeled "Extra Power Supply", can be used for
voltages other than the supply voltage. As an example 12 V for the operation of 12 V relays
or 9 V for phantom power of a MIDI device. It is not necessary to use relays for channel
switching, the use of optocouplers or transistors is also possible, of course.
If the available supply voltages are too high it is also conceivable to connect them first to
the additional power supply for lowering and then connect them to the main power supply.
For example you could bring the voltage down from 15 V to 9 V and then feed it into the
main power supply, which further reduces the voltage to 5V. With regard to cooling, the
same requirements apply as with the main power supply.
Tube-Town GmbH - www.tube-town.net -
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