Motor Drive Amplifier
4840393
RTZ Professional Audio, LLC
3
4. CONFIGURATION JUMPER
Jumper JP1 must be correctly strapped before
the MDA is installed in machine! The MDA card
ships strapped for use with the DTC-1200 or
default non-tension kit equipped machines. You
must change the jumper setting if you plan to
use this MDA card with a legacy Ampex tension
equipped machine.
If the Ampex tension kit is used, jumper JP1
must be set to positions 2 & 3. Otherwise, set
this jumper to the position 1 & 2 for use with the
DTC-1200
controller
or
legacy
Ampex
controllers.
Table 1 - Jumper Configuration
JP1
Jumper Configuration
1 & 2
This jumper position must be
strapped if the MDA is used with
the DTC-1200 controller or the
stock Ampex controller card on
machines not equipped with the
legacy Ampex tension kit.
2 & 3
This jumper position must be
strapped if the MDA will be used
with the legacy Ampex tension kit
equipped machines only.
Refer to
configuration required for your machine. Unless
you plan to use the original Ampex tension kit,
it’s best solder this in position 1 & 2 to avoid any
potential issues that might arise from use of a
removable jumper.
Figure 1 - Jumper Strapping
5. PROTECTIVE FUSES
The RTZ MDA card uses fuses to protect the
MDA card in the event a TO-3 output power
transistor fails/shorts, a power surge occurs or
an over-current situation occurs that exceeds
the time delay fuse limit. A large TVS spike
protection diode is connected with the fuse such
that the fuse will blow in the event of an over
voltage or over current condition.
Check the TO-3 output transistors carefully
should your MDA card ever blow a fuse.
Replace the fuse with the same 500mA SLO-
BLO type specified. Always replace the fuse with
same type shown in Figure 2 below or with an
equivalent replacement fuse type.
Figure 2
– Fuse Replacement
Manufacturer: Bussmann / Eaton
Part Number: BK/S506-500-R
Fuse Type: Time Delay/Slow Blow
Current Rating: 500 mA
Fuse Size: 5 mm x 20 mm
AC Rating: 250 VAC
ALWAYS REPLACE THE FUSE WITH THE
SAME TYPE FUSE OF THE SAME RATING
IN THE EVENT A FUSE EVER BLOWS.
ALWAYS CHECK THE LARGE TO-3
TRANSISTORS ON THE MAIN MD
HEATSINK CAGE IN THE EVENT A MDA
FUSE EVER BLOWS. TYPICALLY, A
BLOWN MDA FUSE INDICATES A
SHORTED TO-3 OUTPUT TRANSISTOR
ON THE MDA HEATSINK.