Technisonic Industries Limited TiL-91-DE/S, Инструкция по установке и эксплуатации

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1.2.2 Transceiver Model TiL-91-DE P/N 901006-2 (continued)
To improve the rejection of interfering signals, dual conversion receiver technology has been
incorporated on the Transmitter/Receiver (Module A1) board used in Model 91-DE Transceiver.
The second IF is 455kHz using a ceramic filter, which is immune to high energy ringing. The
dual conversion module also has a second local oscillator, second mixer and ceramic filter. The
first local oscillator is the original VCO.
The dual conversion receiver board, P/N 003494-1 was implemented into all Technisonic base
stations starting in January 2001. An option label on the chassis will indicate OPTION 94 if
the dual conversion board is installed. It is possible to retro-fit the dual conversion
receiver/transmitter board into older TPS series base station employing the single conversion
board. Please contact Technisonic for availability of an exchange board. Note: If a new A1
Module has been retrofitted the squelch circuit must be aligned for the receiver squelch to
operate correctly.
The dual conversion receiver’s squelch knob must be rotated significantly more clockwise (4
o’clock position) to obtain the same squelch setting (3uV) as a single conversion receiver’s
squelch knob set to the 12 o’clock (straight up) position.
If the dual conversion receiver’s squelch knob is set to the 12 o’clock position, signals with
a level greater than 0.5uV will open the squelch. At most airports this will not be an adequate
level of squelch. Please be aware of this squelch knob adjustment variance when setting and/or
comparing squelch levels of dual conversion vs. single conversion base stations.
1.2.3 Microphone P/N 861902-1
A general view of the Microphone Assembly Part Number 861902-1, Series 1, is given in
Figure 1-2. The microphone is a rugged hand-held microphone housed in a high impact plastic
case. The dynamic microphone is a noise cancelling type with a two-stage preamplifier,
press-to-talk switch, and a retractable three-core cable terminated by a three-pin, male
contacts, connector which mates with the MIC/PTT connector located on the front panel of
the transceiver. The microphone dc supply for the microphone is supplied by the transceiver.
The microphone is stored in the front access cover for transportation.
1.2.4 Blade Antenna P/N 911017-1
A General View of the blade antenna Part Number 911017-1 is given in Figure 1-2. The Blade
Antenna is a broad band, flexible, whip antenna that operates over the entire frequency range
of 117 Mhz to 138 Mhz. The antenna mounts on the rear panel RF BNC connector. A wing nut
provides convenient angle adjustment. The antenna is stored in the front access panel.
1.3 MODES OF OPERATION
1.3.1 Transmit/Receive (Local Mode)
The transceiver may be operated in either of two modes; transmit or receive, as selected by
the Press-to-Talk (PTT) switch on the microphone.
(1) TRANSMIT MODE - When the PTT switch on the microphone is pressed, the
transceiver operates in the transmit mode. The PTT signal line is grounded by the
microphone PTT switch via the microphone lead and the MIC/PTT connector to the
transceiver. The Tx ON amber LED will go ON, indicating that the transmitter is
activated.