ALIGNMENT PROCEDURE AND PERFORMANCE TESTS
8-2
Revised January 1995
Part No. 001-9750-003
c. The meter reading should be 9.5V ± 2.0V. Also
check the other receive test channels. The voltage
should be 3-18 VDC. If this voltage is not within
these ranges, there is a problem with the synthesizer
(the VCO control voltage is not adjustable).
d. Key the transmitter and monitor the transmit signal
with a communications monitor set to the transmit
frequency (815.5125 or 899.0000* MHz). Adjust
the capacitor in TCXO Y800 for the transmit fre-
quency ± 150 Hz.
Figure 8-2 Transmitter Test Setup
8.3 TRANSMITTER TUNEUP
8.3.1 C511 ADJUSTMENT (30 OR 35 WATT
MODELS ONLY)
NOTE: Do not key the transmitter for extended
periods when performing the following adjustments.
NOTE: For accurate power measurement at 800 and
900 MHz, use a minimum number of connectors with a
teflon or better dielectric. If coaxial cable is used, it
should be a minimum length of a low-loss type.
a. Connect the test setup shown in Figure 8-2. Select
the test mode and Ch 001 (851.0125) or Ch 001*
(935.0125) of the RX-TX-RSSI function (see Sec-
tion 3.11.2). An alignment points diagram is located
in Figure 8-4.
b. The test mode POWER SET and TA PWR SET
functions must be preset for maximum power (127).
Refer to Section 8.3.2 for information on how to
make these adjustments.
NOTE: A tuning tool with a 0.030" square tip (JCM
4193) is required to adjust C511 in the next step.
This tool is available from the Service Parts Dept.
by ordering P.N. 721-0015-171.
c. Key the transmitter and adjust C511 for maximum
power output.
d. Rotate the Select switch until the display indicates
Ch 918 TA (869.9625) or Ch 473 TA* (940.9125) to
select the talk-around mode. Key the transmitter and
power output should be greater than the following
levels. If not, readjust C511.
800 MHz
32W
900 MHz
27W
8.3.2 POWER LEVEL 1 ADJUSTMENT
This adjustment sets the power level 1 power
output. Both POWER SET and TA PWR SET are
selected. POWER SET sets the power output on the
low and high ends of the standard band, and TA PWR
SET sets it on the high and low ends of the talk-around
band. This parameter should always be set to the rated
power output because it is used to adjust the power
level across the band.
a. Press and rotate the Select switch to select the
POWER SET function of the test mode (see Section
3.11.3). Press the Select switch to display PWR
SET 1.
b. Key the transmitter and rotate the Select switch to
set the power output for the following level (several
rotations may be required). The relative power out-
put is indicated by 0-127 in the display (127 is max-
imum power). Unkey the transmitter to store the
setting.
15W Models
30/35W Models
800 MHz
15W
35W
900 MHz
15W
30W
c. Rotate the Select switch to display PWR SET 2 and
repeat the preceding adjustment.
* Setting with 900 MHz models
Summary of Contents for Summit DM 975x
Page 105: ...MULTI NET SYSTEM OVERVIEW 5 10 Revised February 1997 Part No 001 9750 005 ...
Page 108: ...CIRCUIT DESCRIPTION 6 3 August 1993 Part No 001 9750 001 Figure 6 1 Transceiver Block Diagram ...
Page 123: ...CIRCUIT DESCRIPTION 6 18 August 1993 Part No 001 9750 001 ...
Page 131: ...SERVICING 7 8 Revised January 1995 Part No 001 9750 003 ...
Page 156: ...9 19 Revised December 2000 Part No 001 9750 007 TRANSCEIVER EXPLODED VIEW PART 1 ...
Page 168: ...Revised January 1995 Part No 001 9750 003 10 11 INTERCONNECT SCHEMATIC ...
Page 169: ...Revised January 1995 Part No 001 9750 003 10 12 DISPLAY BOARD SCHEMATIC ...
Page 171: ...Revised January 1995 Part No 001 9750 003 10 14 RF BOARD SCHEMATIC REVISED 800 MHZ ...
Page 172: ...Revised January 1995 Part No 001 9750 003 10 15 RF BOARD BOARD LAYOUT ALL 800 900 MHZ ...
Page 173: ...Revised January 1995 Part No 001 9750 003 10 16 RF BOARD BOARD SCHEMATIC 900 MHZ ...
Page 174: ...Revised January 1995 Part No 001 9750 003 10 17 RF BOARD BOARD SCHEMATIC UNREVISED 800 MHZ ...
Page 178: ...Revised January 1995 Part No 001 9750 003 10 21 PA BOARD SCHEMATIC 900 MHZ 30W ...
Page 179: ...Revised January 1995 Part No 001 9750 003 10 22 PA BOARD SCHEMATIC 900 MHZ 15W ...
Page 181: ...Revised January 1995 Part No 001 9750 003 10 24 PA BOARD SCHEMATIC UNREVISED 800 MHZ 35W ...
Page 182: ...Revised January 1995 Part No 001 9750 003 10 25 PA BOARD SCHEMATIC UNREVISED 800 MHZ 15W ...
Page 183: ...Revised January 1995 Part No 001 9750 003 10 26 AUDIO LOGIC BOARD SCHEMATIC PART 1 OF 2 ...
Page 184: ...Revised January 1995 Part No 001 9750 003 10 27 AUDIO LOGIC BOARD SCHEMATIC PART 2 OF 2 ...
Page 185: ...Revised January 1995 Part No 001 9750 003 10 28 AUDIO LOGIC BOARD LAYOUT TOP VIEW ...
Page 186: ...Revised January 1995 Part No 001 9750 003 10 29 AUDIO LOGIC BOARD LAYOUT BOTTOM VIEW ...
Page 188: ...Revised January 1995 Part No 001 9750 003 10 31 REMOTE TRANSCEIVER INTERCONNECT SCHEMATIC ...
Page 189: ...Revised January 1995 Part No 001 9750 003 10 32 REMOTE CONTROL UNIT INTERFACE BOARD SCHEMATIC ...
Page 216: ...Part Number 001 9750 007 12 00 hph Printed in U S A ...
