Service manual

1-1
November 2001
Part No. 001-7240-001
GENERAL INFORMATION
1.1 SCOPE OF MANUAL
This service manual contains operation, program-
ming, alignment, and service information for the E.F.
Johnson 7243 LTR-Net
™
portable transceiver.
1.2 TRANSCEIVER DESCRIPTION
The 7243 LTR-Net portable transceiver operates
in the UHF 430-470 MHz frequency range. Power
output is selectable for low (1 watt) and high (4 watt)
levels.
A range of up to 16-100 systems are program-
mable, depending on the type and the number of
groups in each. Systems can be programmed for LTR-
Net, LTR, and conventional operation. Each system
can be programmed with up to 99 groups. Currently, all
transceivers have a telephone keypad and three
programmable option switches. Refer to Section 2.1
for more information on operating features.
1.3 PART NUMBER BREAKDOWN
The following is a breakdown of the part number
used to identify this transceiver.
1.4 TRANSCEIVER IDENTIFICATION
The transceiver identification number is printed
on a label that is attached to the chassis. The following
information is contained in the identification number:
1.5 TRANSCEIVER TUNING
The field tuning procedure is described in
Section 5.
1.6 ACCESSORIES
The accessories available for this transceiver are
listed in Table 1-1. A brief description of some of
these accessories follows:
Extension Test Cable - This cable is required to
operate the transceiver when it has been opened to
access internal components. It reconnects the keypad/
display board to the audio/logic board.
Programming Hardware - The RPI provides the
interface between the programming computer and
242 - 72 x 3 - x x 3
Band
Freq Range
Signaling
Type
3 = High Tier, dual BW
1 = VHF*
4 = UHF
8 = 800 MHz*
9 = 900 MHz*
2 = LTR*
4 = Multi-Net*
5 = SMARTNET/SmartZone*
6 = LTR-Net
0 = Full band (800/
900 MHz)*
1 = 400-440 MHz*
3 = 430-470 MHz
5 = 470-512 MHz*
* These configurations are
currently not available.
Table 1-1 7243 Portable Accessories
Accessory Part No.
Battery pack, nickel metal-hydride hi cap 587-7200-140
Rapid charger base, single unit with
120 VAC power supply
585-7200-023
Antenna, hybrid UHF 585-7200-044
Belt clip 585-7200-032
Extension Test Cable
Contact Cust Serv
Programming Accessories
LTR-Net 7243/98xx programming
software, CD
023-9998-457
PCTune software and test code, CD 023-9998-489
PCFlash soft. & LTR-Net op. code, CD 023-9998-501
Remote Prog Interface (RPI) 023-9800-000
Programming cable (RPI to xcvr) 597-7200-031
DB9 F to DB9 M 6-ft cable 597-5900-002
DB-25 M to DB-9 F 6-ft cable 597-0005-057
DB-25 F to DB-9 M adapter 515-9000-015
7243 x A 25 1 U 12345
Model Revision
Letter
Manufacture
Date
Warrant
y
Numbe
r
Week No.
of Year
Last Digit of Yea
r
Plant
F
rom P.N.
6 = LTR-Net
SECTION 1 GENERAL INFORMATION