Vega C-6124, Техническое руководство

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69 Vega’s C-
6124
An onboard analog oscillator produces the Alert tone. The frequency is fine-tuned by adjusting RV17 while
measuring the frequency at TP5 on the UIM Analog PCB. The consoles are shipped out with the frequency at
1000Hz (+/-10Hz).
9.2.2 Alert tone level
The Alert tone level is set by adjusting RV14 while measuring at TP6 on the UIM Analog PCB. This level is
set relative to the voice audio level. TP6 is the output of the summing amp which drives the transmit bus. All audio
signals, which come from the UIM Analog, are at TP6 at the levels relative to voice that they will be transmitted. At
this point the voice audio has been limited to .77V. The consoles are shipped with the Alert tone 6db below voice.
Since voice is at about .77V, RV14 can be adjusted for an Alert tone level of .39V TP6.
9.3 SWITCH BUS MODULE (SBM)
TX audio across the Switch Bus Module (SBM) is somewhat uneventful. There are no settings on this
module.
9.4 Tone Line Module (TLM) Transmit Path Adjustment
Once microphone audio gets to the TLM it will be routed through a 2175Hz notch filter to remove 2175Hz
components from the voice. This is done to make sure that no component of the microphone audio will interfere with
the 2175Hz hold tone. Out of the notch filter microphone audio is summed together with the last of the signaling
components. TP7 on the TLM is the output of the summing amp that combines microphone audio, DTMF tones,
crosspatch audio, and tone signaling. From this point the total transmit audio mix is sent to the output drivers.
There are two sets of adjustments on the TLM. The internal set is the notch and bus interface settings.
These settings, once set by the factory should not need to be changed. They are placed in an area that requires an
extender card to adjust. The external set of adjustments is the input/output controls that are accessible by only
removing the back panel of the SBM. These controls include, among others, TX output level and RX input level.
9.4.1 External Settings
The C-6124 has been factory set so that voice audio in full compression will be at the same level as the
function tone. This is generally .77V. Press and hold the Release button and then press the Select button without
letting go of the Release button. Let go of both buttons when the red LED in the Instant PTT button lights. This will
produce a function tone. Fully load the card with the load it will see in the system and adjust the RV4 so the output
is at .77V.
9.4.2 Internal Settings
To set every level on the TLM you need an extender card (available from Vega) to remote the TLM. Carefully
consider whether changing these settings necessary. All routine level changes are done from the back of the
console.
9.4.2.1 Tone generator output
The tone generator may be commanded to give a continuous tone out at the function tone frequency by
pressing and holding the Release button and then pressing the Select button. Release both buttons when the
Instant PTT light starts flashing. Adjust RV6 for .77V at TP7. This sets the reference level at TP7 that all other
output levels will be set to. Disengage the tone by pressing the Select button. Jumper JP7 can be used to disable the
tones. To get tones out verify that JP7 is in the A position.
9.4.2.2 Microphone relative output level
Hook up a signal generator to the TB3 terminal block on the back of the UIM analog. Hook audio to pin 3
and the common lead to pin 2. Send in a 2175Hz tone at .77V. Verify that all is well by measuring a .77V, 2175Hz
signal at TP6 of the UIM Analog. Once this is established adjust RV7 on the TLM for .77V at TP3. Verify .77V at
TP7.
9.4.2.3 Crosspatch output level
This level is set just like microphone audio is set. In this case you need to place the card in a crosspatch.
Do this by pressing and holding the Crosspatch Select button and pressing the card Select button. The LED in the
Select button will turn green. Make sure a tone is being inserted to the Aux. Audio terminals (TB3) of the UIM
Analog as described in item 2. Press and hold the XPATCH PTT button on the front of the UIM. You will monitor
the inputted signal at TP12. Adjust RV8 for .77V at TP12.
9.4.2.4 Notch filter adjustment