Marti R-15C User manual

WARNIN
II
THIS EQUIPMENT MUST BE OPERATED WITH A 3-PR
GROUNDED OUTLET RECEPTACLE. FAILURE
TO USE A
PROPERLY GROUNDED OUTLET MAY RESULT IN IMPRO-
PER OPERATION OR SAFETY HA
LIMITEDWARRANTY
The Seller warrants that, at the time of shipment, the
products manufactured by the Seller are free from
defects in material and workmanship. The Seller's
obligation under this warranty is limited to replace-
ment
or repair of such products which are returned to
Marti at its factory, transportation prepaid and
properly insured, provided:
a. Notice of
the claimed defect is given to Marti
within one (1) year [two (2) years for STL systems]
from date of original shipment and goods are returned
in accordance with
Marti instructions.
b. Equipment, accessories,
tubes and batteries not
manufactured by
Marti are subject to only such ad-
justments
as Marti may obtain from the supplier
thereof.
c. This warranty does not apply to equipment which
has been altered, improperly handled, or damaged in
any way.
The Seller is in no event liable for consequential
damages, installation cost or dher costs
of any nature
as a result of the use of the products manufactured or
supplied by the Seller, whether used in accordance
with instructions or not.
This warranty is in lieu of all others, either expressed
or implied. No representative is authorized
to assume
for the Seller any other liability in connection with
Seller's products.
MAILING & SHIPPING ADDRESS:
MARTI Electronics, Inc.
Cleburne,
Texas 76031 -0661
The United States of America
P.O. Box 661 1501
N. MainSt.
COPYRIGHT N
e1993 All Rights Reserved
Mad Electronics, lnc.
2nd printing, August 1993
No part of this manual may be reprodud,
transmitted, transcribed, stored in a retrieval
system,
or translated into any language, natural or comgater,
in any form or by any means, without the prior
written permission of
Marti Electronics, Inc.
Artwork depicting circuitry in this manual is
protected by copyrightlaws.
Information
in this manual is subject to change
without notice and does not represent
a commitmeat
on the part
of Marti Electronics, Inc.
Marti Electronics may make improvements andlor
changes in this manual or in the product
&scribed
herein at any time.
This product could include technical inaccuracies
or
typographical errors.
PHONE NUMBERS:
Sales & Service (81
7) 645-91 63
FAX [phone]
. . .. .

.
Introduction ......................................................................................................... : .............
Specifications ....................................................................................................................
Unpacking and Inspection .................................................................................................
Installation .........................................................................................................................
ElectricalConnections ......................................................................................................
STL System (Stereoand Mono) Block Diagram. No . 702-096 ........................................
Antennas ...........................................................................................................................
Operation ...........................................................................................................................
SystemPerformanceTests ................................................................................................
Theory of Operation ..........................................................................................................
Tools and Test Equipment Required .................................................................................
Frequency Selection(Programming Synthesizer.800-291) ...............................................
Adjustment LocationsDiagram, No . 702-099, R-15C .....................................................
Receiver Test Report .........................................................................................................
Tune-up and Adjustment ..................................................................................................
Block Diagram,No . 702-100. R-15C ...............................................................................
Main Frame
0
1st Converter
890-960MHz
.
1st Converter
280-480MHz
.
1 s t Converter
140-260MHz
.
Frequency Synthe-
sizerBoard
2nd Converter/
IF
Amplifier/ Detector
IF Bandpass Filter
Audio Board
Meter Board
c
Power Supply/
SquelchBoard
Y
Schematic.702-095 .........................................................
Parts List. 702-095 ..........................................................
Schematic.800-211B ......................................................
Parts List. 800-211B ........................................................
Schematic.800-213 .........................................................
Parts List. 800-2 13 ..........................................................
Schematic.800-212 .........................................................
Parts List. 800-212 ..........................................................
Schematic.800-291 .........................................................
Parts List. 800-291 ..........................................................
Schematic. 800-293 .........................................................
Parts List. 800-293 ..........................................................
Schematic. 800-207-250 .................................................
Parts List. 800-207-250 ..................................................
Schematic. 800-294 .........................................................
Parts List. 800-294 ..........................................................
Schematic.800-295 .........................................................
Parts List. 800-295 ..........................................................
Schematic. 800-219A ......................................................
Parts List. 800-219A .......................................................
1
2
4
5
5
7
8
10
12
14
16
17
18
19
25
26
28
29
30
31
34
35
42
43
48
49
52
53
56
57
58
59
64
65
66
67
i

InpuVOutput Filter Schematic, 800-193A ...................................................... 69
Board Parts List, 800-193A ....................................................... 70
-7
.
ii

Introduction
1
1 I
The Marti STL-15C Transmitter with companion R-15C Receiver, form a high quality, fre-
quency synthesized, point-to-point, line
of sight, radio communications link. These systems are
available in frequency bands from 140 MHz to 960 MHz and may be factory configured for op-
eration from various power sources. Depending upon available channel bandwidth, these systems
can transmit
one of the following:
c
Composite FM Stereo audio with two ~ubcarrriers*
Monophonicaudio with two subcarriers
Digitalstereo audio (requires external modems)
0 Multi-channel audio or duta (requires external MUX)
Digitaldata (requires external modems)
Complex systemscan be built from basic STL-15C transmitters and R-15C receivers having mul-
tiple relay (repeaters), bi-directional (full duplex), and automatic switching hot standby features.
I Compositesystem specifications I
Stereo separation:
55 dB orbetter 50 Hz - 15 KHz with 250 KHz IF Filter
50 dB with 200 KHz IF Filter
0
Frequency response:
Composite channel d.2 dB 30 Hz - 53 KHz
Wide band channel a.3 dB 30 Hz - 100 KHz
c
1

Distortion: 0.2% or less 30 Hz - 15 KHz
LPfiltered left
or right channel)
emphasized,LP filtered left or right channel)
Emission: 194 KF8E (without subcarrier)
280 KF8E (with
1 subcarrier)
490 KF8E (with 2 subcarriers)
(demodulated, de-emphasized,
Noise: more than 72 dB below 100% modulation (demodulated, de-
* 940 - 960 MHz system, 500 KHz channels. Narrower bandwidths at reduced specifications.
1 Monophonic system specifications
Frequency response: k0.25 dB
30 Hz - 15 KHz
Distortion: 0.2% or less 30 Hz - 15 KHz
Noise: more than 72 dB below 100% modulation (75 ps de-emphasis)
Emission: 194 KF8E (mono channel with subcarrier)
Pre-emphasis Adjustable 0,25,50, or 75 microseconds
.
Model R45C
Aural STL Receiver
Specifications
Frequency range: 140 - 180 MHz R- 15C/150
R- 15C/215
R- 15C/300
R- 15C/450
R- 15C/950
200
- 260 MHz
280
- 340 MHz
400 - 480 MHz
890 - 960 MHz
2

Sensitivity:
RF Input Impedance
and Connector:
Selectivity:
SpuriousResponse:
Frequency Stability:
Frequency Synthesizer:
MonophonicAudio
.
output:
Composite Audio
output:
SubcarrierOutputs:
Digital Output:
Front Panel Controls:
Composite stereo demodulated,de-emphasized, LPfiltered, or
monaural
3 microvolts input for 50 dB signal/noiseratio
9 microvolts input for 60dB signalhoiseratio
75 microvolts input for ultimate signal/noise ratio (typically 75
dB or better
50 ohms, type UG-58 (N female)
IF filter bandwidth is determined by the subcarrier(s) on the
system and interference conditions. Minimum necessary
bandwidth is selected from options:
Filter
3 dB 60 dB (bandwidth, KHz)
F200 190 450
F250 220 530
F450 280 900
-90 dB, 140-480MHz;
-70 dB, 890-960MHz
k .00025%, -20°C to +50°C
Frequency selected by 16DIP switches,maximumresolution
12.5KHz
Balanced 600ohms, level adjustable
-30 dBm to +10 dBm at
front panel, transformer isolated and floating (may be strapped
for transformerless output)barrier strip terminals. Response
30
HZ - 15 KHZ k 0.25 dB.
Level adjustable 1.8v
P-P to 3.5 v P-P at front panel,
unbalanced BNC connector;composite frequency response
30
HZ - 53 KHZ k0.2 dB.
Two unbalanced outputs,BNC connectors, selectable high pass
filtering for monophonic or composite stereo modes. Subcarrier
output levels are 2
- 3 v. P-P for 10% subcarrier insertion at the
STL-15Ctransmitter. Subcarrierhigh pass filter cut-off
frequency is 25
KHz in “mono mode” and 80 KHz in
“composite mode.”
The 52 “Composite Output”BNC connector can be converted
to
a “Digital” output by connecting an alternate shielded wire
by changing two pins in
a cable connector.The “Digital”
output is unfiltered, unprocessed baseband having a
3 v. P-P
level and a response of 30 Hz - 200 KHz.
10 dB Attenuator, CompositeLevel Adjust, Mono Level
Adjust, Squelch Adjust, and Meter Switch.
a
3

Metering and
Indicators:
Automatic Changeover
:
Accessory connector:
PowerRequirements:
AC Fuse Rating:
Dimensions:
Weight:
Test meter
reads Signal Level, ProgramLevel (mono or
composite),
SubcarrierLevel, AFCLevel, Local Oscillator
Level,
and Mixer Level. LED's indicate AFC Lock,
CompositeMode, Mono Mode,
and SquelchOpen.
Provision for automatic changeover by addition of ARS-2
Automatic Receiver Switcher.
15pin D connector on rear panel provides filtered access to
+13.5 v regulated bus, +18 v unregulated supply, Squelch
relay contacts.
120/220/240VAC*, 50/60 Hz, 20 watts or 11 - 14 VDC
negative ground
or 22 - 28 VDC** negative ground at 600 ma.
(900 ma. initial warmup.
For 120v. use
0.5 Amp fuse
For 220 v. use 0.25 Amp fuse
3.5 inches High x 19inches Wide x 13inches Deep
8.89cm High
x 48.26 cm Wide x 33.02cmDeep
Net
9 pounds. Domestic packed 13pounds.
Net 4.1 kilograms. Export packed 5.9kilograms.
* Voltage must be specifiedwith order.
** Requires APS-28/18PowerSupply.
Specificationssubject
to change without notice
This equipment was factory tested, inspected, packed, and delivered to the
carrier with utmost care.
Do not accept shipment from carrier which shows
damage
or shortage until the carrier's agent endorses a statement of the
irregularityonthe faceof the carrier's receipt.Without documentaryevidence, a
claimcannot befiled.
Unpack equipment immediately upon receipt and thoroughly inspect for
concealed damage.
If damage is discovered, stop further unpacking and
request immediate inspection by localagent of carrier.
A written report of the
agent's findings, with his signature
is necessary to support claim. Check your
shipment against the shipping papers
for possibleshortage. Do not discard any
packingmaterial untilall items are accountedfor. Small items are often thrown
away with packing material. Packing material should be retained until
equipment testing
is completed. Any equipment returnedto the factory should
bepackedinoriginalcartons, insured, andpre-paid.
4

I /nsta//ation
Frequency
Install rack-mounted equipment in
a well-ventilated, well-grounded, and
shielded rack cabinet.
Do not locate
solid-state equipment
in a rack above
tube-type equipment which produces
hightemperatures.
Problems can also be avoided by
locating
this unit away from other
equipment which has transformers
that produce strong magnetic fields.
These fields can induce hum and
noise into the Marti equipment
thus
reducing performance. Strong radio-
frequency
(RF) fields should be
avoided where possible. Extensive
shielding and filtering have been
incorporated into
this equipment to
permit operation
in moderate RF
environments. All equipment racks,
cabinets, etc., should be bonded
together
by wide copper grounding
strap to ensure that all system
elements areat
RF ground potential.
Bandwidth (3dB)
Receiverconnectionsfor
Composite Stereo operation
(Refer to Drawing 702-096)
1. The composite signal output of the R-15C
Receiver is
the BNC jack labeled “52
COMPOSITE”.
The composite output is connected
to the composite signal input of the FM transmitter
exciter by
a shortlength of RAG-58 coaxial cable.
2. A subcarrier demodulator or remote control
(operating above
92 KHz) can be connected to “J1
SUBCARRIER NO. 1”
and/or “J3 SUBCARRIER
NO.
2” output BNCjack. The ability of the STL-ISC
system to transmit subcarriers depends upon
the
channel bandwidth available. The R-15C receiver IF
filter selectivity must be compatible with the available
interference free channel bandwidth. Using
50 KHz
deviation for 100% modulation, the approximate
bandwidth required for various subcarriers follows:
92 KHz
110 KHz
180 KHz
I Subcarrier I Receiver IF I
284 KHz
320 KHz
460 KHz
Actual bandwidth may require an additional 10%
to 15% to allow for the modulation on the subcarrier
itself. With the severe
STL channel crowding with
resulting interference prevalent around large markets,
subcarriers above
110 KHz are not recommended.
3. The accessory connector has several uses such as
remote control, automatic switching,and external DC
power. Connection instructions are furnished with
these accessories.
4. Connect STL receiving antenna coax to “56
ANTENNA”.
This requires a type N male connector.
A short flexible jumper (20” max.) may be used
between
J6 and semi-flexible coax. Marti Part No.
585-017
double shielded, low-loss RG 214/U jumper
is recommended.
5. Connect AC line receptacle on back of the
receiver to a I15 volt AC power source with special
cord set supplied.
USE ONLY 3-PRONG
GROUNDED OUTLET RECEPTACLES FOR
SAFETY.
WARNING
This equipment must be operated
with
a 3-prong, grounded, 11 5 volt,
AC outlet receptacle! Failure to use
a properly grounded outlet could
result in a safety hazard or faulty
equipment performance!
(See nextpagefor receiverconnections for
monophonicoperation.)
5

R-lX Receiver connections
for Monophonicoperation
(Refer to Drawing 702-096)
1. Monophonic program audio output is available at
“600 ohm balanced” audio output screw terminals,
TB-1. Use shielded wire. Program audio output level
is
+IO dBm max, 600 ohms balanced, and isolated
from ground.
For dual channel stereo, repeat
instructions at second receiver. Audio processing
requirements will be discussed
in the “OPERATION’
section of this manual.
2. Connect a remote control
or subcarrier
demodulator to the jack marked,
“51”. The
subcarrier load may be 600 to
5K ohms impedance,
and the output level is approximately one
(1) volt
RMS. Systems factory supplied with 250 KHz IF
bandwidth will carry subcarriers up to
92 KHz. For
other subcarrier frequencies
or narrow IF bandwidth
systems contact the factory. A second subcarrier
system can be connected to
“53”. If a dual channel
stereo
STL is used, connect one subcarrier generator
to
“51” or “53” on each channel’s transmitter and
receiver.
3. The accessory connector has several uses such as
automatic switching, and external DC power.
Connection instructions are furnished with these
accessories.
4. Connect STL receiving antenna coax to, 56
ANTENNA. This requires a type N male connector.
A
short flexible jumper (20” max.) may be used
between
56 and semi-flexible coax. Marti Part No.
585-017 double shielded, low-loss RG-2 14/U jumper
is recommended.
5. For dual channel stereo, use Model MTS-1
Receiver Combiner
between 56 of each receiver.
Use
a Part No. 585-017 jumper between the
ANTENNA connector of the MTS-1 and the semi-
rigid coax. Refer
to Drawing 702-096.
6. Connect AC line receptacle on back of the
receiver to a
115 volt AC power source with special
cord set supplied.
USE ONLY 3-PRONG
GROUNDED OUTLET RECEPTACLES FOR
SAFETY.
WARNING
This equipment must be operated
with a 3=prong,grounded, 11 5 volt,
AC outlet receptacle! Failure to use
a properly grounded outlet could
result in
a safety hazard or faulty
II equipment oerformance! II
.
I
6