Telos Hx1 - T1 Test - 400 Hz Tone Generation; T2 Test - Studio Loopback

bank are set to the OFF position for Factor Default setting, thus no LEDs are lit on the EQ
LO meter).
6.1.3 T1 Test - 400 Hz Tone Generation
Press the hybrid button to advance to the next diagnostic test. e Line Status display
should indicate ‘T1’. e DSP chip on the motherboard generates a 400 sine wave that is sent
to the RCV OUT XLR connector for each hybrid. e output level of the sine wave at the XLR
is +20 dBu, and the output level should be displayed on the RCV meter bargraph. (See gure
below).
e diagnostic test also takes the telephone line o-hook and outputs a –7 dBm, 400 Hz sine
wave. A telephone line or line simulator must be plugged into the LINE RJ11 jack to activate
the telephone interface circuitry on the hybrid motherboard. e 400 Hz tone will also be
audible on the PHONE RJ11 jack, but it will be heard mixed in with the telco’s dial-tone or
re-order tone.
6.1.4 T2 Test - Studio Loopback
Press the hybrid button to advance to the next diagnostic test. e Line Status display
should indicate ‘T2’. is test simply takes audio present on the SEND IN XLR connector
and loops it back to the RCV OUT XLR connector without any processing. e loopback test
works with either analog or AES inputs.
is diagnostic test can be used to adjust the INPUT LEVEL pot located in the back of the
hybrid chassis. Connect a +4 dBu signal and adjust the INPUT LEVEL pot until the yellow
LED segment illuminates. (See gure below).
38 | Section 6