Henry Engineering Turntable Controller MK.II - Manual (Page 2)

UTC INSTALLATION INSTRUCTIONS PAGE 2
CONNECTION TO SP15 TURNTABLES: Remove the turntable from the base, then remove the plastic cover from
the bottom of the turntable. Mount the minijack supplied in the small metal plate next to the Ground post. Carefully
drill a 1/4" hole in the plate and secure the jack using the nut supplied. Be sure that no metal filings drop into the
turntable circuitry!
Connect three wires to the jack; connect each wire within the turntable as follows:
The wire from the sleeve of the jack should be connected to the GROUND POST. Connect the wire from the ring
of the jack to the turntables start-stop switch. Verify the correct switch terminal by checking continuity between the
switch and ground; there should be zero ohms when the start-stop switch is pressed. The wire from the tip of the
jack should be connected to one terminal of the BRAKE SOLENOID. The solenoid will have a diode across its two
terminals; connect the wire to the terminal that has the diode anode wired to it. The anode is the end of the diode
that is not marked with a band. Reassemble the turntable.
CONNECTION TO SP10MKII TURNTABLES: Remove the turntable from the base, then remove the metal cover
from the bottom of the turntable. Carefully remove the small metal plate in which the 'remote' connector jack is
mounted. Unsolder the wires from the jack; remove the jack. Install the three-circuit jack supplied in its place.
Reconnect the ground wire (if any) to the sleeve of the new jack. Reconnect the 'remote start-stop' wire to the ring
of the jack. Connect a length of wire to the tip of the jack. Re-attach the metal plate to the chassis. Connect the
wire from the tip of the jack to the BRAKE SOLENOID of the turntable. The solenoid will have a diode connected
across its terminals; connect the wire to the terminal that has the diode anode wired to it. The anode is the end of
the diode that is not marked with a band. Reassemble the turntable.
CONNECTION TO SP10MK2A TURNTABLES: The SP10MK2A is almost identical to the older SP10MKII. See
paragraph above. Install and wire the three-circuit minijack as described above, except for the wire connected to
the brake solenoid. The wire from the tip of the jack should be connected to the BRAKE SOLENOID
CONNECTOR. The connector, designated "CN-3", is in the lower left corner of the main PC board. Connect the
wire to PIN 1 of the connector. Reassemble the turntable.
CONNECTING THE TURNTABLE TO THE U.T.C.
Connect a length of three-wire cable to the three-circuit miniplug supplied. Standard balanced audio cable (two
wires, plus shield) is ideal. The other end of the cable is connected to the UTC "D" connector. See Figure 2. The
wire from the sleeve of the plug is connected to PIN 1 (GROUND). The wire from the ring is connected to PIN 5
(CONTROL). The wire from the tip is connected as follows:
SP1200MKII OR SP25: CONNECT TO PIN 2, AND INSTALL JUMPER BETWEEN PINS 4 AND 12.
SP15 OR SP10MKII:
CONNECT TO PIN 4, AND INSTALL JUMPER BETWEEN PINS 2 AND 1.
SP10MK2A: CONNECT TO PIN 3, AND INSTALL JUMPER BETWEEN PINS 2 AND 1.
CONNECTING THE U.T.C. TO EXTERNAL CONTROL SWITCHES AND INDICATORS:
The UTC can be controlled by momentary or maintained contact closures, CMOS/TTL gate outputs, open
collectors, or any circuit that switches to ground. (See Figure 2.) Start and Stop switches are connected to PINS 7
AND 8. If a single maintained switch is used, it should be connected to PIN 7; a JUMPER must then be wired
between PIN 8 AND 15. The UTC provides outputs to drive 'Run' and 'Stop' indicator lamps (12 volt, 100 ma max.)
on PINS 9 AND 10. LEDs can be used with a 1000 ohm resistor wired in series with each LED.
Pin 14 is a 'logic' output; it is 'HI' when the turntable is running; 'LO' when it is stopped.
OPERATING INSTRUCTIONS:
Push the START switch to start the turntable; push the STOP switch to stop the turntable. If a maintained switch is
used to control the UTC, opening the switch will stop the turntable. The mode indicators will always indicate either
the RUN or STOP condition. Using the start-stop switch on the turntable will also switch the mode; the UTC will
switch the logic and indicator lamps accordingly. NOTE: When SL1200MKII or SP25 turntables are used, the
STOP indicator comes on about .5 second after the STOP switch is closed. This is normal. The delay occurs only
when going from Run to Stop. The turntable will always start immediately when the START switch is closed.