Standard Horizon Eclipse DSC GX1000S Service Manual

25 Watt VHF/FM DSC Marine Transceiver

ECLIPSE DSC GX1000SECLIPSE DSC GX1000S

ECLIPSE DSC GX1000S

ECLIPSE DSC GX1000SECLIPSE DSC GX1000S

SERVICE MANUAL

Important Note

This transceiver was assembled using Pb (lead) free solder, based on the RoHS specification.
Only lead-free solder (Alloy Composition: Sn-3.0Ag-0.5Cu) should be used for repairs performed on
this apparatus. The solder stated above utilizes the alloy composition required for compliance with the
lead-free specification, and any solder with the above alloy composition may be used.

EM030N90A

1

Specifications

GENERAL

Channels: All USA, International and Canadian
Input Voltage: 13.8 VDC ±20%
Current Drain: Standby 0.3 A

Receive 1.0 A
Transmit 5.5 A (Hi); 1.5 A (Lo)

Individual DSC Directory Memory:15
Dimensions: 2.4” H x 6.1” W x 6.7” D (60 H x 155 W x 170 D mm)
Flush-Mount Dimensions: 2.0” H x 5.2” W x 6.7” D (51 H x 131 W x 170 D mm)
Weight: 1.7 lbs (770 g)

TRANSMITTER

Frequency Range: 156.025 to 157.425 MHz
RF Output: 25 W (Hi); 1 W (Lo)
Conducted Spurious Emissions: 80 dB (Hi); 60 dB (Lo)
Audio Response: within +1/–3 of a 6 dB/octave pre-emphasis characteristic at 300 to 3000 Hz
Audio Distortion:5 %
Modulation: 16K0G3E, for DSC 16K0G2B
Frequency Stability (–20°C to +50°C): ±0.0005%
FM Hum and Noise: 50 dB

RECEIVER

Frequency Range: 156.050 to 163.275 MHz
Sensitivity: 12 dB SINAD 0.25 μV
Squelch Sensitivity (Threshold): 0.15 μV
Modulation Acceptance Bandwidth: ±7.5 kHz
Selectivity (TYP.): –70 dB (Spurious and Image Rejection)

–70 dB (Intermodulation and Rejection at 12 dB SINAD)

Audio Output: 4.5 W
Audio Response: within + 2/–8 of a 6 dB/octave de-emphasis characteristic at 300 to 3000 Hz
Frequency Stability (-20°C to +50°C): ±0.0005 %
Channel Spacing: 25 kHz
DSC Format: RTCM SC101
NMEA Input/Output: Output - DSC, DSE

Input - GLL, GGA, RMC and GNS

Performance specifications are nominal, unless otherwise indicated, and are subject to change without notice.
Measurements are made in accordance with EN301 025. All stated specifications are subject to change without notice or obligation.

2

Exploded View & Miscellaneous Parts

CB4557001
MH-76 ASSY (WHITE)
CB4557002
MH-76 ASSY (BLACK)

RA0976400
RUBBER KNOB (PTT)

RA0976300
RUBBER CAP (MIC)

RA0975700 (WHITE)
RA0975800 (BLACK)
FRONT CASE

RA0976600
RUBBER PACKING (MIC)

RA0976700
HOLDER (PTT)

RA0746700
SHEET (M-TEX1131)

MIC UNIT

g

i

i

RA0974600
LOCK PLATE (MIC)

RA0746700
O RING (8x1.5)

T9207455A (WHITE)
T9207454A (BLACK)
WIRE ASSY

k

k

k

k

RA0975900 (WHITE)
RA0976000 (BLACK)
REAR CASE

l

RA0995200 (WHITE)
RA0995300 (BLACK)
HOOK

RA0978700
MIC HOLDER RUBBER

CS1984401 (w/VR UNIT)
CNTL UNIT

RA0975100
LIGHT GUIDE

G6090184
LCD

MAIN UNIT

RA0973700
CHASSIS (L)

T9207450
WIRE ASSY

j

j

j

j

h

h

h

f

h

RA0974500
LOCK PLATE (DC)

A

c

A

h

f

h

h

c

h

RA0974700
RUBBER PACKING (DC)

c

j

RA0973800
CHASSIS (R)

j

j

RA0974400
SHIELD (POWER)

j

T9207449
WIRE ASSY

RA0422900
O RING

e

e

P1091258
CONNECTOR

RA0973400

Q1094559
POWER MODULE (S-AV37A)

HEATSINK

d

d

d

d

RA0973500 (WHITE)
RA0976800 (BLACK)
SLEEVE

RA0974100
RUBBER PACKING (REAR)

RA0974600
LOCK PLATE (MIC)

CP1986101 (WHITE)
CP1986102 (BLACK)
FRONT PANEL ASSY

RA0422900
O RING (M CONECT)

T9207455A (WHITE)
T9207454A (BLACK)
WIRE ASSY

CP9137001
COVER ASSY (DISTRESS)

RA0973100 (WHITE) (2 pcs)
RA0977000 (BLACK) (2 pcs)
VOLUME KNOB

M4090190
SPEAKER

RA0973300
SP NET

Ú1

Ú2

RA0756900 (2 pcs)
PACKING PAD

Ú1: Accessory with VOL Potentiometer
Ú2: Accessory with SQL Potentiometer

RA0972900 (WHITE)
RA0976900 (BLACK)
FRONT PANEL

RA0973000
RUBBER KNOB

RA0974000
RUBBER PACKING (FRONT)

RA0975500
REFLECTOR SHEET

RA0975400
INTER CONNECTOR

VR UNIT

ACCESSORIES

REF.

c
d
e
f
g
h
i
j
k
l

VXSTD P/N

U05206002
U05307020
U20307020
U24105001
U24106001
U24206002
U24208001
U24210002
U24212020
U24316020

DESCRIPTION

DC CABLE
MIC HOLDER (WHITE)

(BLACK)

MOBILE BRACKET (WHITE)

(BLACK)

BRACKET SCREW (WHITE)

(BLACK)

SCREW SET

DESCRIPTION

CAP SCREW TM2.6X6NI
CAP SCREW TM3X7SUS
BINDING HEAD SCREW M3X7SUS
BIND HEAD TAPTITE-B M2X5
BIND HEAD TAPTITE-B M2X6
BIND HEAD TAPTITE-B M2.6X6NI
BIND HEAD TAPTITE-B M2.6X8
BIND HEAD TAPTITE-B M2.6X10NI
BIND HEAD TAPTITE-B 2.6X12SUS
BIND HEAD TAPTITE-B M3X16SUS

VXSTD P/N

T9025406
RA0436000
RA0458800
RA0978300
RA0978400
RA0978500
RA0978600
U9900147

QTY.

3
4
2
2
1
8
2
8
4
1

Non-designated parts are available only as part of a designated assembly.

3

Exploded View & Miscellaneous Parts

Note

4

Block Diagram

5

Block Diagram

Note

6

Circuit Description

Reception and transmission are switched by 8-bit MPU
IC Q2004 (UPD78F0395GC) on the CNTL Unit. The re­ceiver uses double-conversion superheterodyne circuit­ry, with a 21.4 MHz 1st IF and 450 kHz 2nd IF. The 1st
local is produced by a PLL synthesizer, yielding the 21.4
MHz 1st IF. The 2nd local uses a 21.85 MHz crystal oscil­lator, yielding the 450 kHz 2nd IF. The 2nd mixer and other
circuits use a custom IC to convert and amplify the 2nd IF
and detect FM to obtain demodulated signals. During
transmit, the PLL synthesizer oscillates at the desired fre­quency directly, for amplification to obtain RF power out­put. During transmit, voice modulation is applied to this
synthesizer. Transceiver functions, such as TX/RX control,
PLL synthesizer settings, and channel programming, are
controlled using the MPU.

Receiver

Incoming RF signals from the antenna connector are de­livered to the MAIN Unit, and pass through a low-pass
filter (LPF) consisting of coils L1001 & L1002 and capaci­tors C1003, C1011, & C1024, and antenna switching di­ode D1004 (L308CCB) for delivery to the receiver front
end.

Signals within the frequency range of the transceiver are
passed through a bandpass filter consisting of coils L1006
& L1008 and capacitors C1027, C1036, & C1059, before RF
amplifier Q1022 (3SK294).

The amplified RF is passed through a bandpass filter con­sisting of coils L1022, L1026, & L1027 and capacitors
C1145, C1150, C1115, C1159, C1170, C1174, & C1179. The
pure in-band input signal is delivered to the main 1st mixer
Q1028 (3SK131).

Buffered output from the MAIN VCO is amplified by
Q1018 and Q1019 (both 2SC5006) and low-pass filtered
by coils L1009 & L1011 and capacitors C1064, C1071, &
C1076, to provide a pure 1st local signal between 134.625
and 136.025 MHz for delivery to the main 1st mixer.

The 21.4 MHz 1st mixer product is passed through the
monolithic crystal filter XF1001 (±6.5 kHz BW), and is
amplified by Q1036 (2SC4400).

After that, it delivered to the input of the FM IF subsystem
IC Q1029 (TA31136FNG). This IC contains the 2nd mix­er, 2nd local oscillator, limiter amplifier, FM detector, noise
amplifier, and squelch gates.

The 2nd local in the FM IF subsystem IC Q1029
(TA31136FNG) is produced from crystal X1001 (21.850
MHz), and the 1st IF is converted to 450 kHz by the 2nd
mixer and stripped of unwanted components by ceramic
filter CF1001.

After passing through a limiter amplifier, the signal is
demodulated by the FM detector. Demodulated audio
from the FM IF subsystem IC Q1029 (TA31136FNG) is
amplified by Q1038 and Q1033 (both 2SC4154). The am­plified signal is passed through the AF mute switch Q1031
(2SK2035) and the front panels volume control. The ad­justed audio signal is delivered to the AF power amplifi­er Q1039 (LA4425A).

The amplified audio signal is delivered to the 8 Ohms in­ternal loudspeaker and external Speaker terminal in the
accessory cable.

PLL Synthesizer

The 1st Local signal maintains stability from the PLL syn­thesizer by using a 21.850 MHz reference signal from crys­tal X1001. PLL synthesizer IC Q1026 (TB31202FNG) con-
sists of a prescaler, reference counter, swallow counter,
programmable counter, a serial data input port to set these
counters based on the external data, a phase comparator,
and a charge pump.

The PLL synthesizer IC divides the 21.850 MHz reference
signal by 1748 using the reference counter (12.5 kHz com­parison frequency).

The VCO output is divided by the prescaler, swallow
counter and programmable counter. These two signals are
compared by the phase comparator, and applied to the
charge pump.

A voltage proportional to their phase difference is deliv­ered to the low-pass filter circuit, then fed back to the VCO
as a voltage with phase error, controlling and stabilizing
the oscillating frequency. This synthesizer also operates
as a modulator during transmit.

The VCO consists of Q1019 (2SK210GR) and varactor di-
odes D1009 and D1011 (both HVU359), which oscillates
at 21.4 MHz below from the receiving frequency while
receiving, and oscillates at the fundamental transmit fre­quency during a transmit with direct frequency-modula­tion using varactor diode D1010 (1SV214). The VCO out­put passes through buffer amplifier Q1018 and Q1017
(both 2SC5006) to obtain stable output, then applied to
the 1st mixer of while receiving, and to the driver ampli­fier Q1008 (2SC5006) during a transmit.

The DC supply for the VCO is regulated by Q1016
(2SC4154).

7

Circuit Description

Transmitter

The voice from the microphone is passed through the
CNTL Unit to the microphone amplifier Q1001
(LM2902PW) on the MAIN Unit, a pre-emphasis network,
limiter (IDC: instantaneous deviation control), and low­pass filter network, the audio is adjusted for optimum de­viation level.

The voice or DSC (Digital Selective Calling) encoded sig­nal from the low-pass filter network Q1001 (LM2902PW)
is applied to the VCO Q1019 (2SK210GR) which oscil-
lates at the fundamental transmit frequency with direct
frequency-modulation using varactor diode D1010
(1SV214). The modulated signal is amplified by the buff­er amplifier Q1018 and Q1017 (both 2SC5006), then
passed through the diode switch D1006 (DAN235U) to
drive amplifiers Q1008 (2SC5006) and RF power ampli­fier module Q1014 (S-AV37A).

The RF energy then passes through antenna switch D1003
(L308CCB) and low-pass filter (LPF) consisting of coils
L1001 & L1002 and capacitors C1003, C1011, & C1024, and
finally to the antenna connector.

RF output power from the RF power amplifier module
Q1014 (S-AV37A) is sampled by C1014 and C1021 and is
rectified by D1002 (1SS321). The resulting DC is fed
through Automatic Power Controller Q1007 (RT1N441U)
to RF power amplifier module Q1014 (S-AV37A), thus pro-
viding positive control of the power output.

Generation of spurious products by the transmitter is min­imized by the fundamental carrier frequency being equal
to the final transmitting frequency, modulated directly in
the transmit VCO. Additional harmonic suppression is
provided by a low-pass filter consisting of coils and ca­pacitors, resulting in more than 80 dB of harmonic sup­pression prior to delivery of the RF energy to the antenna.

DSC Encoder/ Decoder

Encoder

The DSC (Digital Selective Calling) encode signal which
D/A converted in the 8-bit MPU Q2004 (UPD78F0395GC)
on the CNTL Unit is fed through the low-pass filter Q1001
(LM2902PWR) on the MAIN Unit to the VCO Q1019
(2SK210GR).

Decoder

A portion of the demodulated signal from the FM IF sub­system IC Q1029 (TA31136FNG) is passes through the
low-pass filter Q1037 (2SC4154) to the DSC Decoder IC
Q1034 (NJM2211M). The decoded DCS signal delivered
to the 8-bit MPU IC Q2004 (UPD78F0395GC) on the
CNTL Unit.

1050 Hz Weather Alert Decoder

The 1050 Hz Weather Alert signal from the buffer ampli­fier Q1033 (2SC4154) is applied to 8-bit MPU IC Q2004
(UPD78F0395GC) on the CNTL Unit.

MPU

Operation is controlled by 8-bit MPU IC Q2004
(UPD78F0395GC) on the CNTL Unit. This MPU uses a

18.432 MHz crystal X2001 for the system clock. IC Q2003
(PST597CN) resets the MPU when the power is on.

EEPROM

The EEPROM Q2006 (BR24L08FVT) on the CNTL Unit
retains TX and RX data for all memory channels, prescal­er dividing, IF frequency, local oscillator injection side,
and reference oscillator data.

8

Alignment

The GX1000S has been carefully aligned at the factory
for the specified performance across the marine band.

Realignment should therefore not be necessary except in
the event of a component failure. All component replace­ment and service should be performed only by an autho­rized Standard Horizon representative, or the warranty
policy may be voided.

The following procedures cover the sometimes critical and
tedious adjustments that are not normally required once
the transceiver has left the factory. However, if damage
occurs and some parts are replaced, realignment may be
required. If a sudden problem occurs during normal op­eration, it is likely due to component failure; realignment
should not be done until after the faulty component has
been replaced.

We recommend that servicing be performed only by au­thorized Standard Horizon service technicians who are
experienced with the circuitry and fully equipped for re­pair and alignment. Therefore, if a fault is suspected, con­tact the dealer from whom the transceiver was purchased
for instructions regarding repair. Authorized Standard
Horizon service technicians realign all circuits and make
complete performance checks to ensure compliance with
factory specifications after replacing any faulty compo­nents.

Those who do undertake any of the following alignments
are cautioned to proceed at their own risk. Problems
caused by unauthorized attempts at realignment are not
covered by the warranty policy. Also, Standard Horizon,
a division of Vertex Standard must reserve the right to
change circuits and alignment procedures in the interest
of improved performance, without notifying owners.
Under no circumstances should any alignment be attempt­ed unless the normal function and operation of the trans­ceiver are clearly understood, the cause of the malfunc­tion has been clearly pinpointed and any faulty compo­nents replaced, and the need for realignment determined
to be absolutely necessary.

The following test equipment (and thorough familiarity
with its correct use) is necessary for complete realignment.
Correction of problems caused by misalignment result­ing from use of improper test equipment is not covered
under the warranty policy. While most steps do not re­quire all of the equipment listed, the interactions of some
adjustments may require that more complex adjustments
be performed afterwards. Do not attempt to perform only
a single step unless it is clearly isolated electrically from
all other steps. Have all test equipment ready before be­ginning, and follow all of the steps in a section in the or­der presented.

Required Test Equipment

 RF Signal Generator with calibrated output level at

200 MHz

 Deviation Meter (linear detector)
 AF Millivoltmeter
 SINAD Meter
 Inline Wattmeter with 5% accuracy at 200 MHz
 Regulated DC Power Supply: 13.8 VDC, 10A
 50-ohm Non-reactive Dummy Load: 30W at 200 MHz
 Frequency Counter: >0.1 ppm accuracy at 200 MHz
 AF Signal Generator
 DC Voltmeter: high impedance
 VHF Sampling Coupler
 AF Dummy Load: 4 Ohms, 10 W
 Oscilloscope
 Spectrum Analyzer
 CP180 GPS/Chart Plotter
 GX5500S Marine Transceiver

Alignment Preparation & Precautions

A dummy load and inline wattmeter must be connected
to the main antenna jack in all procedures that call for
transmission. Correct alignment is not possible with an
antenna.

After completing one step, read the following step to de­termine whether the same test equipment will be required.
If not, remove the test equipment (except dummy load
and wattmeter, if connected) before proceeding.

Correct alignment requires that the ambient temperature
be the same as that of the transceiver and test equipment,
and that this temperature be held constant between 68 °F
and 86 °F (20 °C and 30 °C). When the transceiver is
brought into the shop from hot or cold air it should be
allowed some time for thermal equalization with the en­vironment before alignment. If possible, alignments
should be made with oscillator shields and circuit boards
firmly affixed in place. Also, the test equipment must be
thoroughly warmed up before beginning.

Note: Signal levels in dB referred to in this procedure are

based on 0 dBμ = 0.5 μV (closed circuit).

9

Alignment

Main Reference Frequency Adjustment

 Setup the test equipment as shown below.

Sampling

50-ohm

Dummy Load

Frequency

Counter

 Set the channel to CH16.
 Use the [H/L] key to set the transceiver to “LOW”

power.

 With the PTT switch pressed, adjust TC1001 so that the

Frequency Counter reading is 156.800 MHz ±100 Hz.

VR1001

Coupler

ANT

GX1000S

Transmit Power Adjustment

 Setup the test equipment as shown below.

50-ohm

Dummy Load

 Set the channel to CH16.
 Use the [H/L] key to set the transceiver to “HI” power.
 With the PTT switch pressed, adjust VR1001 so that

RF output power is 24 W ±0.3 W.

 Release the PTT switch, then set the transceiver to

“LOW” power by the [H/L] key.

 With the PTT switch pressed, adjust VR1002 so that

RF output power is 0.8 W ±0.1 W.

 Release the PTT switch.

Inline

Wattmeter

ANT

GX1000S

L1022

VR1002

L1027

VR1003

TC1001

JP1001

L1022

L1012

L1010

TP1008

10

MAIN UNIT ALIGNMENT POINT