Hx1-Hx2 Manual-1.4.1 - Telos

12 | section 2
try connecting pin 3 of the Hx input to ground, or even “floating” the ground and using only the
high and low pins on the Hx. It’s also important that unbalanced lines be kept short to avoid
hum and noise pickup. You’ll probably need to adjust the input gain on the Hx to match the
output of your device. We also suggest that all of your audio equipment be powered from the
same AC power source or circuit to prevent ground loops due to the use of multiple grounds.
For complete information and suggested wiring and grounding techniques for your studio or
recording workstation, please visit the support page at the Telos website:
http://www.telos systems.com/support.
2.5 Output Audio Connection
The output connection, RCV OUT, has the following characteristics:
♦ XLR Pin 1 = Ground,
♦ XLR Pin 2 = High (Active Balanced, RF suppressed)
♦ XLR Pin 3 = Low (Active Balanced, RF suppressed)
♦ Output impedance, < 60 Ohms
♦ Analog clip point at +24 dBu
♦ Digital-to-Analog converter resolution of 24 bits
The nominal output level is fixed at +4 dBu, with +20 dBu headroom to account for the crest
factor of some audio signals.
If you are connecting the output of your Hx to a device with an unbalanced input, connect the
shield from your device’s unbalanced input to pin 1 (ground) on the Hx, and the “hot” lead from
your device to pin 2. It’s important that unbalanced lines be kept short to avoid hum and noise
pickup. We also suggest that all of your audio equipment be powered from the same AC power
source or circuit to prevent ground loops due to the use of multiple grounds. For complete information
on suggested wiring and grounding techniques for your studio or recording workstation,
please visit the support page at the Telos website: http://www.telos-systems.com/support.
2.6 Remote Control
The female DB9 connector on the Back Panel provides access to control functions. Pin 1 of the
DB9 connector is Ground. Pins 2 through 5 on the top row are for GPIO input signals from
the remote device, while Pins 6 through 9 on the bottom row are GPIO output signals to the
remote device. Two of the GPIO input pins and two of the GPIO output pins are reserved for
each hybrid as follows:
Hx Remote
Connector
GROUND
Pwr 5vdc
C
10k
D
L
1 6
Inputs 2-5 Outputs 6-9**
General internal Schematic of Hx
Remote Control port
** Please review manual for current limitations per GPIO outputs
5
9
L
GROUND