Tait T805, Руководство по обслуживанию

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M805-00
ASP Card Operation 4.3
Copyright TEL 30/09/96
4.1 T805-03 Test Signal Generator
Module (TSGM)
Figure 4.1 TSGM Block Diagram
The TSGM's primary functions are to generate the test tones for the equaliser training
process and to distribute audio to the LEMs during normal operation. It can also sup-
ply a 2970Hz tone for keying the system transmitters.
The TSGM has two audio inputs:
- the first is for speech from the source;
- the second is for the optional external source of CTCSS tones.
Note:
If required, the TSGM may be programmed to internally generate its own
CTCSS tone and to optionally generate reverse phase burst CTCSS.
The TSGM has two audio outputs:
- output 1 is used for training tones/speech/key tones in the 300Hz to 3kHz fre-
quency range (HF audio);
- output 2 is used for training tones/CTCSS in the 67 to 300Hz frequency range
(LF audio).
In addition there is a digital output called "DIGOUT" which provides the synchronisa-
tion pulse or "start gun" required by the LEMs during the training process.
When the system is operating normally in pass mode (i.e. not in the training mode), the
TSGM passes the normal speech audio (0-3200Hz for software v2.09, v2.10 & v2.11;
0-2550Hz for v2.12 & v2.13) from the appropriate input (depending on system configu-
ration) to output 1, and after that to all the LEMs. The signal path followed will depend
on the system type to which the Quasi-Synchronous system is connected (refer to Sec-
tion 5). The CTCSS tone (67-300Hz) for the system is sourced from audio output 2 and
follows a different path from that of the speech.
All speech audio for the Quasi-Synchronous system is passed through the TSGM. For
systems which have the AIM/ARM combinations fitted, two or three methods of key-
ing the transmitters may be used, depending on the software version used:
A/D
Audio
amps
Audio
buffer
Audio
buffer Audio
amps
A/D
Audio
buffer
Audio
buffer Audio
amps
DSP
processor
D/A
D/A
Audio
amp
Audio
amp
Electronic
relay
Electronic
relay
1
3
4
2
1
2
Digout
N/C
HF audio
(speech or
training tones)
LF audio
(CTCSS or
training tones)
Start gun
pulse
Speech
audio
N/C
External CTCSS
(optional)
ICCS
Tx key
(v2.12 & later)