Marti STL-10A.pdf

MARTI ELECTRONICS

STL TRANSMITTER

MODEL STL–10AOctober, 2001 597–9500

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TECHNICAL MANUAL

MARTI ELECTRONICS

STL-10A BROADCAST STL TRANSMITTER

TABLE OF CONTENTS

DESCRIPTION PAGE NO.

INTRODUCTION – STL–10A 1SPECIFICATIONS 3UNPACKING AND INSPECTING 5INSTALLATION 5

STL–10A TRANSMITTER INSTALLATION 5ANTENNA INSTALLATION 6

STL ANTENNA INSTALLATION CHECKLIST 6ANTENNA ASSEMBLY 6TRANSMISSION LINE CONNECTOR ASSEMBLY 6MOISTURE PROOFING COAX CONNECTORS AND FITTINGS 6LOCATION AND GROUNDING OF COAXIAL CABLE 7SYSTEM GROUNDING 7ANTENNA INSTALLATION AND ADJUSTMENT 7

OPERATION 7SWITCH AND METER FUNCTIONS 7

TRANSMIT–OFF SWITCH AND LED 7FORWARD–REFLECTED SWITCH AND RF POWER METER 8PEAK MODULATION METER 8TEST METER 8PRE–EMPHASIS SWITCHES 9FREQUENCY MEASUREMENT 9

STL–10A PERFORMANCE TESTS 9NOISE 10DISTORTION 10FREQUENCY RESPONSE 10

STL–10A THEORY OF OPERATION 10POWER SUPPLY 800–168 10INPUT/OUTPUT FILTER 800–193A 10CONTROL BOARD 800–197 10AUDIO BOARD 800–194 11MODULATOR 800–195 11MULTIPLIER BOARD 800–163 11RF POWER AMPLIFIER 800–374B AND 800–373B 11DUAL LINK STEREO STL 11TEST EQUIPMENT 14TOOLS FOR ALIGNMENT OF STL–10A SERIES TRANSMITTERS 14

Marti Electronics 2000 ALL RIGHTS RESERVED Printed in the U.S.A.

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DESCRIPTION PAGE NO.

TUNE–UP PROCEDURE FOR STL–10A 14MODULATOR CIRCUIT BOARD 800–195 ADJUSTMENTS 14STL–10A TRANSMITTER TEST REPORT 15AUDIO CIRCUIT BOARD 800–194 ADJUSTMENTS 16MULTIPLIER CIRCUIT BOARD 800–163 ADJUSTMENTS 16RF POWER AMPLIFIER BOARD 800–374B AND 800–373B 16ADJUSTMENTSPOWER CONTROL POT CALIBRATION 16B+ ADJUST 17FORWARD POWER METER ADJUST 17REVERSE POWER METER ADJUST 17PA CURRENT ADJUST 18FREQUENCY MEASUREMENT 18

STL-10A PARTS LIST 22

STL-10A SCHEMATICS 33

LIST OF ILLUSTRATIONS

FIGURE NO. TITLE PAGE NO.

1 STL–10A TRANSMITTER 12 STEREO STL SYSTEM BLOCK DIAGRAM – 702–058 23 FCC EMISSION PROFILE (500 KHZ CHANNEL) DRAWING 124 FCC EMISSION PROFILE (200 KHZ CHANNEL) DRAWING 135 STL–10A TRANSMITTER BLOCK DIAGRAM 196 STL–10A ADJUSTMENT LOCATIONS 207 STL–10A MAIN FRAME 21

LIST OF TABLES

TABLE NO. DESCRIPTION PAGE NO.

1 STL–10A ELECTRICAL AND PHYSICAL 4SPECIFICATIONS

2 STL-10A PARTS LIST 19

WARNINGTHIS EQUIPMENT MUST BE OPERATED WITH A 3–CONDUCTORGROUNDED AC POWER RECEPTACLE . FAILURE TO USE A PROPERLY GROUNDED RECEPTACLE MAY RESULT IN IMPROPEROPERATION OR A SAFETY HAZARD .

LIMITED WARRANTYThe Seller warrants that, at the time of shipment, theproducts manufactured by the Seller are free from de-fects in material and workmanship. The Seller’s obliga-tion under this warranty is limited to replacement or re-pair of such products which are returned to Marti at itsfactory, 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] fromdate of original shipment and goods are returned in ac-cordance with Marti instructions.

b. Equipment, accessories, tubes and batteries notmanufactured by Marti are subject to only such adjust-ments as Marti may obtain from the supplier thereof.

c. This warranty does not apply to equipment whichhas been altered, improperly handled, or damaged inany way.

The Seller is in no event liable for consequential dam-ages, installation cost or other costs of any nature as aresult of the use of the products manufactured or sup-plied by the Seller, whether used in accordance with in-structions or not.

This warranty is in lieu of all others, either expressed orimplied. No representative is authorized to assume forthe Seller any other liability in connection with Seller’sproducts.

MAILING & SHIPPING ADDRESS:

MARTI Electronics4100 North 24th StreetQuincy, Illinois 62301

The United States of America

COPYRIGHT NOTICE

2000 All Rights ReservedMarti Electronics

No part of this manual may be reproduced, transmitted,transcribed, stored in a retrieval system , or translatedinto any language, natural or computer, in any form orby any means, without the prior written permission ofMarti Electronics.

Artwork depicting circuitry in this manual is protectedby copyright laws.

Information in this manual is subject to change withoutnotice and does not represent a commitment on the partof Marti Electronics.

Marti Electronics may make improvements and/orchanges in this manual or in the product described here-in at any time.

This product could include technical inaccuracies or typographical errors.

PHONE NUMBERS:

Sales (817) 735–8134Sales FAX (817) 735–9340Service (217) 224–9600Service Fax (217) 224–9607

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INTRODUCTION – STL–10A.The MARTI STL–10A Studio Transmitter Link/Inter–city Relay is a line–of–sight FM communications system pro-viding a high quality broadcast audio channel with two optional sub–channels. A dual link for stereo provides twoidentical broadcast quality channels with better than 70 dB stereo cross–talk and four optional sub–channels. Thesesystems offer greater rejection of interference, superior noise performance, much lower channel cross–talk, andgreater redundancy than currently available composite STL systems.

APPLICATIONS OF THE STL–10A SYSTEM (FCC Approved Parts 74, 101):

• STL for FM stereo broadcast (dual system)

• STL for AM stereo broadcast (dual system)

• STL for FM monaural or AM monaural broadcast

• Inter–city relay for linking two or more broadcast facilities

• Multi–relay system for radio network distribution

• Communications link between satellite earth station and broadcastfacilities

• Data and Background Music links

• Private microwave service

Complex systems can be built from basic STL–10A transmitters and R–10 receivers having multiple relay (repeat-ers), bi–directional (full duplex), and automatic switching hot standby features (refer to Figure 2).

Features of the STL–10A Transmitter include:

� FCC approved under Parts 74 and 101.

� User selectable audio processing provides 0, 25, 50, or 75 microsecond pre–emphasis options.

� Low–pass filters designed to eliminate overshoot on complex audio waveforms.

� Calibrated RF watt meter for forward and reflected power.

� Test meter on front panel indicates Subcarrier Level, Supply Voltage, PA Current, Forward and Reflected Power. Additional test points are located inside transmitter.

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FIGURE 2. STEREO STL SYSTEM BLOCK DIAGRAM – 702–058

COPYRIGHT 2000 MARTI ELECTRONICS

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� Automatic output power control. The power control maintains the output power to a specific level and is independent of temperature and voltage changes.

� Twelve segment bar graph for display of peak transmitter modulation. The five highest LED’s (100% to 250%) have a “peak–hold” feature which will display instantaneous peak value for one second, a valuable feature when dealing with pre–emphasizedprogram audio.

� Automatic switching capability by addition of Model ATS–15E Transmitter Switcher

� Accessory plug for external DC power, remote control, remote metering, and other functions

� Low power consumption for operation on AC, solar cell, battery, or other single–polarity DC source. (Marti Model UPS–12 Uninterruptible Power System).

� Terminal strip for a balanced 600 ohm audio input, BNC jack for unbalanced audio, Sub 1, and Sub 2 inputs.

The Marti STL–10A system derives its excellence from Marti’s experience in supplying thousands of such systemsworld–wide over the past thirty years. This equipment incorporates state–of–the–art technology and is manufacturedin modern, efficient facilities under high quality–control standards.

STL–10A System Specifications

FreqRangeMHz Transmitter

MaximumPower

MaximumDeviation Receiver

ReceiverIF

BandwidthSystem Specifications

Frequency Response Distortion Noise

850–960 STL––10/950 10 watts ±50 KHz R–10/950 200 KHz ±0.25 dB, 20–15000 Hz 0.25% or less –80 dB or better

System specifications shown are for 200 KHz receiver IF bandwidth. Narrow band channels requiring 85 KHz IFbandwidth have ±0.25 dB response, 0.3% distortion.

System Applications

FreqRangeMHz Application

FCCPart

B.W.Each

Channel Frequency Response Distortion NoiseChannel

Separation

850–960 FM Stereo STL 74 200 KHz ±0.25 dB, 20–15000 Hz 0.25% or less –80 dB or better 80 dB

850–960 FM Stereo STL 74 150 KHz ±0.3 dB, 20–15000 Hz 0.3% or less –72 dB or better 72 dB

850–960 AM Stereo STL 74 100 KHz ±0.3 dB, 20–15000 Hz 0.3% or less –72 dB or better 72 dB

928–960 Data or Background Music 94 100 KHz ±0.3 dB, 20–15000 Hz 0.3% or less –72 dB or better 72 dB

928–960 4–channel Sat. Pgm. Feed 94 100 KHz ±0.3 dB, 20–15000 Hz 0.3% or less –70 dB or better 70 dB

Stereo System Differential Phase 0.5 degrees or less SPECIFICATIONS SUBJECT TO CHANGE WITHOUT NOTICE

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TABLE 1. STL–10A ELECTRICAL AND PHYSICAL SPECIFICATIONS

(Sheet 1 of 2)

PARAMETER SPECIFICATION

ELECTRICAL

FREQUENCY BAND 850 MHz to 960 MHz as specified.

MAXIMUM POWER OUTPUT 10 watts, ±0.5 watts,850 to 960 MHz.

OUTPUT CONNECTOR UG–58 (Type N Female)

OUTPUT IMPEDANCE 50 Ohms

MODULATION Direct FM

STABILITY ±0.00025%

SPURIOUS EMISSIONS More than 60 dB below carrier.

AUTOMATIC CHANGEOVER Provision for automatic changeover by addition of ATS–15E Automatic Switcher

AUDIO INPUTS Balanced 600 Ohms, +8 dBm, barrier strip. BNC connectors for unbalanced input.

SUBCARRIER INPUTS Two BNC connectors for remote control and/orsubcarrier inputs. 50–600 ohms unbalanced, 3 V. P–P for10% injection.

METERING/INDICATORS Precision “Peak–hold” Bar Graph Modulation Meter. Illuminated RF Wattmeter indicates Forward Power, Reflected Power. Test Meter reads PA Current,Subcarrier Level, 13.5 Volt Supply, and RF Drive 1, RF Drive 2. LED indicates Transmit.

CONTROLS TRANSMIT switch, TEST METER switch, POWER ADJUST Pot.

POWER REQUIREMENTS 120–220 volts ac * 50–60 Hz, 80 watts. 13.5 volt dc at 4 Amperes.

AC POWER SUPPLY Precision, electronically regulated with current/temperature limiting.

ACCESSORY CONNECTOR 15–pin “D” connector for dc power, remote control, automatic changeover and remote power metering.

FUSE 4 Amp Slo–Blo for 115 V operation. 1.25 Amp Slo–Blo for 230V operation. Type 3AG.

PHYSICAL

DIMENSIONS 19 in.(48.26 cm.) wide x 3.5 in. (8.89 cm.) high x 14 in. (35.56 cm) deep.

WEIGHT Net 11 pounds. Domestic packed 18 pounds.Net 4.9 kilograms. Export packed 8.2 kilograms.

TYPE ACCEPTANCE NUMBER FCC ID: DDESTL–10–950(FCC PART 101 & PART 74)

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TABLE 1. STL–10A ELECTRICAL AND PHYSICAL SPECIFICATIONS

(Sheet 2 of 2)

PARAMETER SPECIFICATION

ENVIRONMENTAL

OPERATING TEMPERATURE –20°C to +50°C (–4°F to +122°F).RANGE

* Voltage must be specified with order.

** Requires APS–28/18 Power Supply

UNPACKING AND INSPECTING.This equipment was factory tested, inspected, packed, and delivered to the carrier with utmost care. Do not acceptshipment from the carrier which shows damage or shortage until the carrier’s agent endorses a statement of the irreg-ularity on the face of the carrier’s receipt. Without documentary evidence, a claim cannot be filed.

Unpack equipment immediately upon receipt and thoroughly inspect for concealed damage. If damage is discov-ered, cease further unpacking and request immediate inspection by a local agent of the carrier. A written report ofthe agent’s findings, with his signature is necessary to support the claim. Check your shipment against the shippingpapers for possible shortage. Do not discard any packing material until all items are located. Small items are oftenthrown away with packing material.

The packing material should be retained until equipment testing is completed. Any equipment returned to thefactory should be packed in the original cartons, insured, and pre–paid.

INSTALLATION.NOTE

NOTE

INSTALL RACK–MOUNTED EQUIPMENT IN A WELL VENTI-LATED, GROUNDED, AND SHIELDED RACK CABINET.

Install rack–mounted equipment in a well ventilated, grounded, and shielded rack cabinet. Do not locate solid–stateequipment in a rack above tube–type equipment which produces high temperatures. Problems can also be avoidedby locating this unit away from other equipment which has transformers that produce strong magnetic fields. Thesefields 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 equip-ment to permit operation in moderate RF environments. All equipment racks, cabinets, etc., should be bondedtogether by wide copper grounding strap to ensure that all system elements are at the same RF ground potential.

STL–10A TRANSMITTER INSTALLATION.

1. Program audio output is connected to balanced audio input screw terminals. Use shielded wire. Program audio level required is +8 dBm, 600 ohms balanced and isolated from ground. For dual channel stereo repeat instructions at second transmitter. Audio processing requirements will be discussed in OPERATION.

2. Connect a Remote Control or Subcarrier Generator (modulator) to the jack marked “J1 SUB IN”. The subcarriersource may be 50 to 600 ohms impedance, and the input level required is approximately one (1) volt RMS. Subcarrier frequencies may be between 39 KHz and 67 KHz. Systems factory supplied with 200 KHz IF bandwidths will carry subcarriers up to 92 KHz. For other subcarrier frequencies or narrow IF bandwidth systems contact the factory. A second subcarrier generator can be connected to J3. If a dual channel stereo STL is used connect one subcarrier generator to J1 on each channel’s transmitter.

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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 transmitting antenna coax to “J6 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.

WARNING

WARNING

THIS EQUIPMENT MUST BE OPERATED WITH A 3–PRONG,GROUNDED, 115 VOLT, AC OUTLET RECEPTACLE. FAILURETO USE A PROPERLY GROUNDED OUTLET COULD RESULTIN A SAFETY HAZARD OR FAULTY EQUIPMENTPERFORMANCE.

5. For dual channel stereo, use only Marti Part No. 585–017, 20.5 inch double shielded jumper between J6 of each transmitter and the indicated connectors of the HRC–10B Series Combiners. Use a third Part No. 585–017jumper between the “ANTENNA” connector of the HRC–10B and the semi–rigid coax. Refer to Drawing 702–058.

6. Turn transmitter off. Connect the ac line receptacle on back of the transmitter to a 115 volt AC power source with special cord set supplied. Use only 3–prong grounded outlet receptacles.

ANTENNA INSTALLATION.

STL Antenna Installation Checklist.

The following suggestions are offered to help those responsible for antenna installations avoid costly errors in as-sembly and adjustment. Marti Electronics Inc. assumes no responsibility for the installation and performance of antenna systems associated with the equipment. The following text presents a listing of some of the most frequentlyasked questions associated with the equipment. The text is not intended to be a complete step–by–step procedure.

Antenna Assembly.

Follow the manufacturer’s instructions carefully. If no instructions were included with the antenna, call or write theantenna manufacturer for instructions. Errors are frequently made in assembly of the RF feed dipole elements whichmust be installed in the same plan as the reflector grids. In other words, if the reflector grid elements are horizontal,then the feed dipole elements must also be horizontal. Cross polarization of grid and feed dipole will result in totalloss of antenna gain.

Transmission Line Connector Assembly.

Do not use RG–58 U or RG–8 U cable for STL station antennas. They have too much loss at VHF and UHF fre-quencies. Follow the instructions furnished by the manufacturer when cutting the coaxial cable. Inspect the cableends for small metal fragments which can short–circuit the line inside the connector assembly. Check the line for ashort–circuit condition after each connector is installed using an Ohmmeter. Pressurized line should be checked forseveral days under pressure before installation on a tower to ensure that there are no leaks in the line or fittings.

Moisture Proofing Coax Connectors and Fittings.

Extreme care must be exercised with coaxial cable before and after connectors have been installed to ensure thatmoisture does not enter the line. Foam dielectric line can absorb moisture absorption which is difficult to detect andremedy. Therefore, keep the line dry while in storage with the ends tightly capped. Coaxial splices, connectors, andfittings, to be located outside should be made mechanically tight, then coated with a weather–proofing material suchas SCOTCHKOTE over at least two layers of SCOTCH 88 vinyl plastic electrical tape. Moisture problems in antenna systems are usually traced back to connectors which have NOT been properly taped. The Marti K–1grounding and weatherproofing kit is recommended for use in each new antenna installation.

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Location and Grounding of Coaxial Cable.

Keep the STL receiver coaxial cable as far from the broadcast transmitter and coaxial cable as possible. DO NOTSTRAP RECEIVER CABLE TO THE MAIN ANTENNA CABLE AT ANY POINT. PLACE THE RECEIVERANTENNA COAXIAL CABLE ON THE OPPOSITE SIDE OF THE TOWER FROM THE MAIN ANTENNACABLE. Maintain maximum separation between these cables at all points, including the distance from tower base totransmitter building as well as inside the building.

System Grounding.

It is essential that the STL antenna system be properly grounded for safety and proper operation. Ensure the antennasystem is properly grounded.

Antenna Installation and Adjustment.

The polarization of the transmit and receive antennas of the STL system must be the same. This means that if thetransmitting antenna is horizontal, the receiving antenna must also be horizontal. Each antenna should be attached tothe tower to allow for final adjustment in azimuth heading and vertical tilt.

After visual adjustment of the antennas, the transmitter and receiver can be used to make the final adjustments of theantennas. With the transmitter driving one antenna, the receiving antenna is adjusted for maximum signal (indicatedon the receiver) in both horizontal and vertical directivity. CAUTION: Antennas have a “major” and several “minor” lobes in their directivity patterns. A common error is to peak the antenna on a minor lobe, resulting in asignal level of only a fraction of the major lobe signal. This error can be avoided only by swinging the antennathrough a large angle so that all lobes are evaluated and the major lobe clearly determined. After one antenna is ad-justed, the transmitter and receiver locations are reversed, to allow adjustment of the other antenna. If an RF watt-meter is available, each antenna and transmission line can be checked for VSWR when the transmitter is supplyingpower to it. The VSWR should be less than 1.5 to 1 (1.5:1).

If the antenna system fails to give the predicted signal strength level, check the following items:

1. Check for correct assembly of antenna.

2. Ensure the antennas have same polarity.

3. Check orientation of antennas in both horizontal and vertical directions.

4. Check VSWR of both the transmit and receive antennas. VSWR should be less than 1.5:1.

5. Check for required Fresnel zone path clearance at all points along radio path.

6. Check for obstructions in the path such as trees and man–made structures. Do not depend on maps or aerial photographs.

WARNING

WARNING

YOU CAN BE KILLED IF AN ANTENNA COMES IN CONTACTWITH ELECTRIC POWER LINES OR EXPOSED ELECTRICALWIRING. FOR YOUR SAFETY USE EXTREME CAUTION WHENINSTALLING ANTENNAS. KEEP AWAY FROM POWER LINES.

OPERATION.

SWITCH AND METER FUNCTIONS.

TRANSMIT–OFF Switch & LED.

This toggle switch controls the RF output of the transmitter. The red LED above this switch is a visual indicationthat the switch is in “TRANSMIT ” position. The audio circuits, the 13.5 volt regulated power supply and the meterillumination lamps remain on when the TRANSMIT switch is “OFF”.

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FORWARD–REFLECTED Switch & RF Power Meter.

The RF POWER METER , with its selector switch, allows monitoring parameters within the transmitter as follows:

1. When switched to “FORWARD POWER”, the meter indicates the RF power output of the STL–10A transmitter. The maximum power is 10 Watts for the 850–960 MHz band (United States).

2. When switched to “REFLECTED POWER ”, the TEST METER indicates the amount of power returning on the coaxial line from the antenna. This is useful in determining the VSWR (Voltage Standing Wave Ratio) for theantenna system. The lower the VSWR for a given forward power, the better. Most antennas guarantee a VSWR of less than 1.5 to 1.

The table below gives VSWR for various reflected powers:

ForwardPower

ReflectedPower

VSWR

10 Watts (890–960 MHz) 0.3 watts 1.4010 Watts (890–960 MHz) 0.4 watts 1.5010 Watts (890–960 MHz) 0.5 watts 1.5710 Watts (890–960 MHz) 0.7 watts 1.7010 Watts (890–960 MHz) 1.0 watts 1.90

PEAK MODULATION Meter.

A “peak–hold” twelve segment bar graph display is included on the STL–10A transmitter for setting and monitor-ing peak STL modulation (composite or mono mode). The five highest LED’s (100% to 250%) have a “peak–hold”feature which will display an instantaneous peak value for one second. This is a valuable feature when dealing withpre–emphasized program audio. The procedure for setting peak modulation is to adjust audio input level into theSTL–10A until the 100% bar is flashing on audio peaks. The 110% through 250% bars indicate over–modulationand require a reduction in input level to obtain a 100% peak indication.

TEST Meter.

The TEST METER with its selector switch, allows monitoring of five important parameters within the transmitteras follows:

1. “SUB LEVEL ” – Indicates subcarrier injection. 0 VU is approximately 20% injection. For 10% injection use –6 VU. Subcarrier voltage at J1 or J3 is approximately 1 volt for 20% injection, 0.5 volts for 10%.

2. “+13 VOLT SUPPLY” – Indicates regulated voltage supply operation. +1.5 VU is approximately 13.5 VDC.

3. “P.A. CURRENT” – The collector current of the final amplifier and its driver is calibrated to read “0 VU” on the meter at rated power output and efficiency. The POWER ADJUST potentiometer should never be set to produce a P.A. current greater than 0 VU.

4. “FORWARD POWER”. The transmitter forward power level.

5. “REFLECTED POWER ”. The transmitter reflected power level.

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PRE–EMPHASIS SWITCHES.

Two programmable switches S1 and S2 on audio board 800–194 enable the user to select flat, 25, 50, or 75micro–second pre–emphasis characteristics. The selection of one of these options in the transmitter requires a corresponding selection of S1 and S2 on receiver audio board 800–205. Refer to STL–10A adjustment location dia-gram at the end of this manual for the location of these switches. The switches, as shown in the diagrams, are positioned for 75 micro–seconds at the factory. 75 micro–second pre–emphasis and de–emphasis produces the bestthreshold noise performance in an FM system. It does however present problems in modulation control. Some users therefore may wish to use 50 micro–second, 25 micro–second, or flat processing. AM stations will find flatprocessing desirable since the STL can be treated as a pair of wires in proof of performance tests without possibleovermodulation of the link at high audio frequencies. With 75 micro–second pre–emphasis, audio input levels to thetransmitter should be reduced 20 dB below 100% modulation when running frequency response tests to prevent overmodulation at the higher audio frequencies. With a full quieting RF signal into the receiver, flat pre–emphasiswill produce a system signal–to–noise ratio approximately 6 dB less than 75 micro–second pre–emphasis. Receivedsignal levels less than full quieting may produce a difference of as much as 13 dB between flat and 75 micro–secondpre–emphasis.

FREQUENCY MEASUREMENT.

The RF output frequency of this transmitter should be measured and adjusted as often as necessary to insure on–frequency operation and to comply with regulations (refer to TUNE–UP PROCEDURE in the following text).

STL–10A SYSTEM PERFORMANCE TESTS.The STL–10A transmitter, R–10 receiver with the associated antenna system can be tested and compared with facto-ry test data included in this manual. The following procedures should be followed in order to obtain reliable and accurate results.

Before audio tests or subcarrier tests are begun check the receiver “SIG. LEVEL” METER for required minimumsignal. A conversion from VU to microvolts is given under OPERATION in the R–10 receiver manual. For a 950MHz system using 50 KHz FM deviation, typical noise levels are:

1 uV for 20dB S/N ratio

3 uV or 50 dB S/N ratio

10 uV for 60 dB S/N ratio

20 uV for 70 dB S/N ratio

50+ uV for ultimate S/N ratio

For the above system with 20% subcarrier injection, the following noise level on the subcarrier (Marti SCG–10 – SCD–10 System) was measured: (no modulation main or sub).

10 uV for 40 dB Subcarrier S/N ratio



150 uV for ultimate Subcarrier S/N ratio

With ultimate S/N ratio, main to sub crosstalk should be –40 to –45 dB (using Marti SCG–10 – SCD–10 SubcarrierSystem).

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NOISE.

Noise measurements should be made first, since high noise levels will influence distortion readings. Also groundloops in the audio oscillator to transmitter connections and distortion analyzer to receiver connections must be resolved before testing begins. The influence of high RF fields upon the test equipment must be determined and corrected before accurate measurements can be made. NOTE: NOISE AND DISTORTION MEASUREMENTSARE MADE WITH SUBCARRIER AND REMOTE CONTROL INPUT SIGNALS REMOVED. System signal tonoise ratio is determined while modulating the transmitter 100% at 400 Hz. A level of +8 dBm across the balancedaudio input terminals of TB–1 will produce a reading of 100% modulation on the “PEAK MODULATION” indicator. Set Receiver “PGM LEVEL ADJ” pot for +10 dBm output into the distortion analyzer. If the distortionanalyzer has a high impedance input, add a 600 ohm load resistor to match the receiver. Establish +10 dBm on theaudio voltmeter of the analyzer as the reference level for 100% modulation. Next, remove the audio signal from thetransmitter input and measure noise level below reference (100% modulation). This reading should compare withthat published under SYSTEM SPECIFICATIONS in this manual.

DISTORTION.

Harmonic distortion is usually measured at 100% modulation and at several frequencies. If pre–emphasis processingis used in the transmitter with corresponding de–emphasis in the receiver, it is normal for available audio level at thereceiver to drop with increasing frequency according to the de–emphasis curve selected. At 15 KHz, there is sufficient level to operate most modern distortion analyzers. Distortion levels should be within specifications. If distortion is out of specs, check system noise, check for test equipment ground loops, RFI, and transmitter/receiveroperating frequency. If either unit is off frequency, the FM modulation sidebands are not centered within the IF filterbandpass, which can cause audio distortion.

FREQUENCY RESPONSE.

If the STL–10A System is switched to flat processing, frequency response can be measured as if the signal were be-ing sent over straight wires. If pre–emphasis processing is used (especially 75 micro–seconds) allowance must bemade in the transmitter audio input level to prevent over–modulation at test frequencies above 400 Hz. The simplestand fastest method is to set the transmitter audio input level for 100% modulation at 400 Hz, then attenuate this level20 dB. Set receiver output level to –10 dBm as the reference, then sweep the audio band for response. Responseshould be within limits published in the SYSTEM SPECIFICATIONS.

STL–10A THEORY OF OPERATION.Refer to the STL–10A block diagram in the DRAWINGS AND PARTS LIST section for the following discussion.

POWER SUPPLY 800–168.

Power supply circuit board 800–168 contains filter capacitor C5, and reverse polarity protection diodes D5, D6 andD7. The unregulated output voltage of this supply is 17–20 volts. The voltage is supplied from bridge rectifierD1–4 on circuit board 800–168.

INPUT/OUTPUT FILTER 800–193A.

Radio–frequency filters are installed on all input/output circuits connected to ACCESSORY connector J4, as well asthe AC line input.

CONTROL BOARD 800–197.

Applies an operating voltage to the unit.

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AUDIO BOARD 800–194.

The 600 ohm balanced audio input to the transmitter is connected to the inputs of unity gain differential amplifierIC–1A. Potentiometer R9 is provided for adjusting the amplifier to produce the maximum common mode rejection(CMR). The output of the differential amplifier is directly coupled to the pre–emphasis amplifier. The negativefeedback circuit of this amplifier has two capacitors selected by switches S1 and S2 which provides options of 0, 25,50, or 75 microsecond pre–emphasis. Following the pre–emphasis circuit are two stages of active Butterworth low–pass filtering. The signal is then routed to the MODULATOR audio input and to metering amplifiers IC–3A andIC–3B. The subcarrier input is routed to the MODULATOR subcarrier input.

MODULATOR 800–195.

The MODULATOR consists of voltage controlled crystal oscillator Q2, buffer amplifier Q3, subcarrier modulatorD2, precision voltage regulator IC–1 and oven heater control Q1. Precise frequency control is obtained by thermallycoupling components Y–1, Q1, Q2, and IC–1 to temperature regulated frequency control module 800–160–1.Coarse and fine frequency adjustment is provided by L1 and L2 while the main channel modulation is provided by avoltage variable capacitance diode in the frequency control module. Bias for this diode is obtained through voltagedivider resistors R4, R5, and R7. Diode D1 temperature compensates the bias supply. Components L3, C13 and D2permit phase modulation of the subcarrier information upon the RF output of transistor Q3.

MULTIPLIER BOARD 800–163.

The modulator RF output is frequency–multiplied in the multiplier board to obtain the various operating frequencieslisted on the STL–10A specification sheet. The power level at the input to the multiplier is approximately 5 mw.The output level is 0.7 to 1.2 watts.

RF POWER AMPLIFIER 800–374B AND 800–373B.

The RF power amplifier consists of two boards; the PA Interface board (800–374B) and the Two–Stage RF PowerAmplifier board (800–373B). Up to 1 watt RF power from the Multiplier board (800–163) at a frequency rangingfrom 445 to 480 MHz is fed into the 10/15C PA Interface board (800–374B). The purpose of this board is to doublethe incoming frequency, amplify the doubled frequency and filter out all other frequencies. This board also providesa means for controlling the RF power level via the front panel POWER ADJUST POT. An automatic level control(ALC) circuit stabilizes and maintains an accurate output power level. A 50 mW (max), 890–960 MHz signal fromthis board is fed into the two stage RF Power Amplifier board. The RF goes through two stages of RF amplification.The first stage (U2) is a 1 watt (max) pre–driver. It has an input and output transformer (T1 and T2) for achievingoptimum 50 ohm matching between the stages. The output of T2 is fed into the final PA module (U3) for an outputof 15 watts max. The signal is then low–passed filtered through FL1 and then fed through a directional coupler formonitoring forward and reflected power. This board also provides regulated B+ for powering the PA and the rest ofthe chassis. Finally, there also exist circuitry for regulating the fan and monitoring PA current.

DUAL LINK STEREO STL.

Two STL–10A Links can share the same 500 KHz, 300 KHz, or 200 KHz channel for transmission of left and rightstereo components, as shown in the STEREO STL SYSTEM BLOCK DIAGRAM, Drawing No. 702–058. A systemoperating in this manner uses no more spectrum (and possibly less) than “COMPOSITE” systems, while providingmuch lower channel cross–talk (72 dB). Since the two links are independent, if one link fails, continued operation inmono service is assured. Phase shift between channels can be less than 1 degree. The two carriers are offset aboveand below the channel center frequency as shown in the following FCC EMISSION PROFILE Drawings. Offsets are125 KHz for 500 KHz channels, 75 KHz for 300 KHz channels, and 50 KHz for 200 KHz channels. Using a MartiHRC–10 Transmitter Combiner having 40 dB isolation, all sidebands and IM products are well within the limits ofSubpart E of FCC Rules Part 74.535. Optional transmitter combiners are available which provide 70 dB or 100 dBof isolation. Receiver IF selectivity required in this system is 200 KHz for 500 KHz channels, 85 KHz for 300 KHzchannels and 75 KHz for 200 KHz channels.

12


FIGURE 3. FCC EMISSION PROFILE (500 KHZ CHANNEL) DRAWING

13

FIGURE 4. FCC EMISSION PROFILE (200 KHZ CHANNEL) DRAWING


14

TEST EQUIPMENT.

The following text presents the test equipment required for alignment of STL–10A Transmitters. A sample test re-port is also provided in the following text.

1. Bird, Model #43, Wattmeter, 50 ohm impedance.

2. Bird, 25–Watt Element, 400–1000 MHz.

3. Microwave Associates, 50–Watt RF Load, Model 44003.

4. Kron–Hite, Distortion Analyzer, Model 6900B.

5. Kron–Hite, Oscillator, Model 4500.

6. Hewlett Packard, Attenuator Set, Model 350D.

7. Signoteck Frequency Counter.

8. Hewlett Packard, Spectrum Analyzer, Model 8558B.

9. Wavetek, Automatic Modulation Meter, Model 4101.

10. Wavetek, Digital Multimeter, Model 27XT.

12. Kay, RF Attenuator, Adjustable 0–110 dB, Model 437A.

13. Marconi, RF Signal Generator, Model 2022C.

TOOLS FOR ALIGNMENT OF STL–10A SERIES TRANSMITTERS.

1. GC, 9300, Tuning Tool.

2. GC, 9440, Tuning Tool.

3. Spectrol, 8T000, Tuning Tool.

4. Sprague–Goodman, Tuning Tool.

TUNE–UP PROCEDURE FOR STL–10A.

MODULATOR CIRCUIT BOARD 800–195 ADJUSTMENTS.

Connect a dummy load with a sampling attenuator to the ANTENNA connector J6 of the transmitter. Connect anaccurate standard FM deviation meter and frequency counter to the sampling attenuator or J5 the FREQUENCYTEST JACK. Operate the CONTROL switch to TRANSMIT.

1. Measure the bias voltage at TP (test point) of modulator circuit board 800–195 using digital dc voltmeter. This voltage should be recorded on STL–10A TRANSMITTER TEST REPORT. To ensure low distortion modulation, do not change this voltage setting.

2. Operate the transmitter on frequency by adjusting L2 (fine) coil slug using correct insulated tool. If necessary, L1 (coarse adjustment) can be made using the insulated tool specified.

3. Monitor the PEAK MODULATION LED bar and feed a 400 Hz, +8 dBm signal from an audio signalgenerator into TB–1. The PEAK MODULATION meter should read 100%. If not, adjust R24 (modulation meter calibrate) on audio circuit board 800–194 for 100% on PEAK MODULATION meter. The FMdeviation meter should read the deviation specified under 100% modulation on STL–10A TRANSMITTER TEST REPORT. If not, adjust R6 on modulator circuit board 800–195.

4. Remove the 400 Hz tone. Feed the audio signal generator set for 67 KHz at one (1) volt into J1 Sub In. Operate the TEST METER switch to SUB LEVEL and adjust audio signal generator level for a meter readingof 0 VU. Adjust R11 for a 20% sub–carrier injection as indicated on the linear vertical display on a spectrum analyzer.

15

STL–10A TRANSMITTER TEST REPORT

CUSTOMER: _________________________________________________________________________

ADDRESS: ___________________________________________________________________________

FREQUENCY: ______________________________

Serial #: ______________________________

Modulator Bias: __________________

100% Modulation __________________________ +kHz.

Total DC Current __________________________ amperes

TEST POINT READINGS

TP 1 __________ 0.15 V dc – 0.60 V dc

TP 2 __________ 0.70 V dc – 1.90 V dc

TP 3 __________ 0.50 V dc – 1.00 V dc

TP 4 __________ 0.50 V dc – 1.90 V dc

TEST METER READINGS

Subcarrier Level: 0 VU = 20%

+13 Volt Supply: +1 VU = 13.5 Volts DC

P.A. Current: 0 VU = Normal

TEST EQUIPMENT

Frequency Counter, HP Model 5383ADeviation Monitor, Wavetek Model 4101

SIGNATURE: ______________________________________

DATE: ____________________________________________

16

AUDIO CIRCUIT BOARD 800–194 ADJUSTMENTS.

1. Connect an audio voltmeter to Pin 1 (modulator audio) of audio circuit board 800–194. Connect a jumper between terminal 1 and 2 (the outer terminals) of TB–1 (the 600 ohm balanced input). Connect an audiosignal generator between chassis and either Terminal 1 or 2. Operate the generator for a 100 Hz output at 1 volt. Increase sensitivity of the audio voltmeter until the 100 Hz output component is indicated. Adjust R9 (CMR, Common Mode Rejection) for a minimum common mode output.

2. Set S1 and S2 on audio circuit board 800–194 for 75 micro–second pre–emphasis with S1 and S2 positioned toward R15. Remove the jumper and feed the audio signal generator into terminals 1 and 2 of TB–1. Operate the generator to 15 KHz and adjust the level for 0.78 volts (0 dBm) output on the audio voltmeter. Operate the generator to 400 Hz and observe audio voltmeter. The level at 400 Hz should be exactly 17 dB below the level at 15 KHz. If not, return to 15 KHz and adjust R15 by the amount in error at 400 Hz. Repeatprocess until the exact pre–emphasis is obtained.

3. Modulation meter calibration is covered in the modulator circuit board 800–195 adjustments.

MULTIPLIER CIRCUIT BOARD 800–163 ADJUSTMENTS.

Remove the top cover of the unit. Remove the coaxial cable plug at RF Output jack J2 of on multiplier circuit board800–163. Refer to the STL–10A ADJUSTMENT LOCATIONS diagram for the location of connectors, test pointsand adjustments.

1. Connect a Bird Model #43 Wattmeter with a 5–watt element and a 50 ohm load to J2 of multiplier circuit board 800–163. Connect sensitive multimeter (0–3 volt DC range) negative probe to TP–1 of multiplier board and the positive probe to chassis ground. Operate the CONTROL switch to TRANSMIT. A minimum of 0.25 volts should be indicated. If not, refer to MODULATOR CIRCUIT BOARD ADJUSTMENTS in the preceding text.

2. Move the meter negative probe to TP–2. Adjust L1 and L2 for a maximum indication.

3. Move the meter negative probe to TP–3. Adjust L3 and L4 for a maximum indication.

4. Move the meter negative probe to TP–4. Adjust L5 and L6 for a maximum indication.NOTE: Omit this step on the 140–180 MHz units.

5. Move the meter negative probe to TP–5. Adjust C27 and C28 for a maximum indication. Turn “POWER ADJUST” pot, R14 for maximum power.

6. Adjust C36 and C37 for a maximum indication on the wattmeter connected to J2 with the R14 power pot operated to maximum. Adjust power level to .75 to 2 watts output.

7. Operate the CONTROL switch to OFF. Remove the wattmeter from J2 and re–install coaxial cable plug at J2. Adjust R14, “POWER ADJUST”, for correct transmitter output power.

RF POWER AMPLIFIER BOARD 800–374B AND 800–373B ADJUSTMENTS.

The RF Power Amplifier is very broad–band and has been fully calibrated and adjusted at the factory. The only adjustments available are POWER CONTROL POT calibration, B+ adjust, FORWARD POWER METER adjust,REFLECTED POWER METER adjust, and PA CURRENT adjust. These adjustments should only be made as necessary and with extreme care by following the procedures below:

For the following adjustments, switch “TRANSMIT” off and connect an accurate RF wattmeter and dummy loadrated for at least 25 watts at 800 to 1000 MHz to the RF output “N” connector. Remove top cover of unit. Pleasecarefully read procedures before doing them.

POWER CONTROL POT CALIBRATION.

1. On the Interface board, rotate the POWER CALIBRATION POT (R4) fully counter–clockwise.

2. On the front panel of unit, rotate the POWER CONTROL POT fully counter–clockwise.

3. Rotate R20 on the two–stage RF power amplifier board fully counter–clockwise.

17

4. Turn on “TRANSMIT” switch. The wattmeter should read approximately 0 watts.

5. Rotate R20 on the RF power amplifier board approximately 6 turns clockwise.

6. On the front panel of unit, slowly rotate the POWER CONTROL POT clockwise watching the wattmeter for any significant power. Keep rotating the POWER CONTROL POT until the control is fully clockwise. If the output power exceeds 5 watts during the adjustment, proceed as follows:

A. Rotate R20 on the RF power amplifier board clockwise until the output power is between 1 and 5 watts.

B. Continue to rotate the POWER CONTROL POT until the control is fully clockwise.

7. With the POWER CONTROL POT in full clockwise position, begin slowly rotating the POWER CALIBRATION POT (R4 on 10/15C PA Interface Board) clockwise at the same time watching the wattmeter climb in power. Keep rotating the control until the desired maximum output power is obtained. Do not exceed 10 watts.

8. Once the POWER CONTROL POT is adjusted, do not re–adjust POWER CALIBRATION POT R4 onthe 10/15C PA Interface Board or R20 on the RF power amplifier board.

9. Replace top cover.

B+ ADJUST.

1. Using a VOLTMETER, with negative lead connected to ground (chassis), connect the positive lead to a B+ location (refer to any schematic – B+ wiring is red and goes to every PC board).

2. On the two–stage RF Power Amplifier board adjust Pot (R5) in the direction required to achieve a B+ readingof 13 volts. Adjust this voltage with the “TRANSMIT” switch on and the output power at 10 watts.

3. Perform (or redo) the POWER CONTROL POT CALIBRATION procedure.


FORWARD POWER METER ADJUST.

1. With the “TRANSMIT” switch on, adjust the POWER CONTROL POT (on front panel) such that the wattmeter reads 10 watts.

2. Put the front panel ROTARY switch in the forward power position.

3. Adjust R8 (on meter board just inside front panel) until the front panel meter reads 10 watts.

4. Verify calibration by adjusting POWER CONTROL POT and comparing the wattmeter reading with the frontpanel. They should closely agree as power changes.


REFLECTED POWER METER ADJUST.

1. With the “TRANSMIT” switch on, adjust POWER CONTROL POT such that the wattmeter reads 10 watts.

WARNING

WARNING

READ AND UNDERSTAND THE FOLLOWING STEPS BEFOREPERFORMING THEM. IT IS IMPORTANT THAT THESE STEPSBE PERFORMED WITHIN A SHORT PERIOD OF TIME.

2. Put the front panel ROTARY switch in the reflected power position.

3. With the “TRANSMIT” switch still on, remove the RF output cable from the “N” connector on the back of the unit.

4. Adjust R9 (on meter board just inside front panel) until the front panel meter reads 10 watts.

18

5. If R9 is turned as far as it can be turned and the front panel meter is still below the 10 watt reading, adjust R17 on the two–stage RF Power Amplifier board until the front panel meter does indicate 10 watts.

6. Reconnect the RF output cable to the “N” connector. Verify that the power (from the wattmeter reading) goesback to 10 watts and the front panel reflected power meter reading falls to less than 1 watt.


PA CURRENT ADJUST.

1. Turn on “TRANSMIT” switch.

2. Adjust output power to 10 watts using POWER CONTROL POT on front panel.

3. Put the front panel ROTARY switch in the PA CURRENT position.

4. Adjust R10 (on the meter board just inside front panel) so that the front panel meter indicates 100%.

5. Verify by adjusting output power up and down watching the PA CURRENT meter reading following the trend.


FREQUENCY MEASUREMENT.

The RF output frequency of this transmitter should be measured and adjusted as often as necessary to insure on–frequency operation and to comply with regulations. Frequency measurement can be made by coupling off theRF output via a wattmeter or a 30 dB (or more) 50 watt attenuator into a frequency counter.

19

FIGURE 5. STL–10A TRANSMITTER BLOCK DIAGRAMCOPYRIGHT 2000 MARTI ELECTRONICS

20

FIGURE 6. STL–10A ADJUSTMENT LOCATIONSCOPYRIGHT 2000 MARTI ELECTRONICS

FIGURE 7. STL–10A MAIN FRAME21

22

STL–10A PARTS LIST

PARTS LIST

950 MULTIPLIER

Loc. Marti No. Description

R14 100–101 Potentiometer, 100 ohm Mallory MR100P

R12 145–030–C Resistor, 3.3 ohm 1/4 watt 5% carbon comp 30BJ250

R1 145–102 Resistor, 1k ohm 1/4 watt 1% metal film Mepco SFR55 1K 1%TR


R11 145–103 Resistor, 10k ohm 1/4 watt 1% metal film Mepco SFR25


R3 145–151 Resistor, 150 ohm 1/4 watt 1% metal film Mepco SFR25



R4 145–272 Resistor, 2.7k ohm 1/4 watt 1% metal film Mepco SFR25



R16 145–472 Resistor, 4.75K ohm 1/4 watt 1% metal film Mepco SFR25



R6 145–680–C Resistor, 68 ohm 1/4 watt 5% carbon comp 30BJ250

R9 145–680–C Resistor, 68 ohm 1/4 watt 5% carbon comp 30BJ250

C11 217–103 Capacitor, .1 mf 100v 10% mylar OSG2A104K BULK



C2 217–104 Capacitor, .01 mf 50v GMV disc Pace F7Z5U1C103Z–TR



C27 230–103 Capacitor, variable 1.3–5.4 pf T3–5 EFJ 187–0103–005



C36 230–106 Capacitor, variable 1,7–11 pf t6–5 EFJ 187–0106–005

C24 241–120 Capacitor, uncased mica 12pF 5% FWM602



C31 253–471 Capacitor, 470 pf 50v 10% Y5P disc Pace F6Y5P1C471K–JT

C13 255–010 Capacitor, 1 pf 5% type QC



23

C12B 255–030–1 Capacitor, 3 pf 5% NPO disc Pace F5NPO1C3ROC–TR

C19 255–110 Capacitor, 11 pf 5% NPO disc RMC CC110BJIAA25

C21 255–140 Capacitor, 14 pf 5% NPO disc RMC CC140BJIAA25

C1 255–220 Capacitor, 22 pf 5% NPO disc Pace F5NP01C220J–JT

C12A 255–270 Capacitor, 27 pf 5% NPO disc Pace F5NP01C270J–TR

C22 255–270 Capacitor, 27 pf 5% NPO disc Pace F5NP01C270J–TR

C14 255–390C Capacitor, 39pF 5% 200V ceramic dipped C322C390J2G5CA



C15 255–750 Capacitor, 75 pf 5% NPO disc Pace F6NP01C750J–JT (BULK)

C8 256–151 Capacitor, 150 pf 5% NPO disc Pace F6NP01C151J–JT

C10 268–102 Capacitor, .001 mf 50v disc –20+80% Pace F5Z5U1C102Z–JT








C3 268–203 Capacitor, .02 mf 50v Z5U disc 140–50Z5–223M XICON

C26 270–102 Capacitor,monolithic chip,1000pf 50v 5%KemetC1206C102J5GACTR

C33 299–220 Capacitor, tantalum, 2.2 mf 25v ECS–F1EE225K Panasonic

L5 350–038 Inductor, 1 1/2 turn brown Coilcraft 144–01J12S

L6 350–038 Inductor, 1 1/2 turn brown Coilcraft 144–01J12S

L3 350–039 Inductor, 2 1/2 turn red Coilcraft 144–02J12S

L4 350–039 Inductor, 2 1/2 turn red Coilcraft 144–02J12S

L1 350–040 Inductor, 6 1/2 turn blue Coilcraft 144–06J12S

L2 350–040 Inductor, 6 1/2 turn blue Coilcraft 144–06J12S

L13 350–118 Inductor, 1–1/2 turn 14 AWG Buss Wire (CCW)

L10 350–120 Inductor, 1 1/2 turn 14 AWG Buss Wire (CW)



L12 350–121 Inductor, 10 turn .15 uH #90–03

D1 412–494 Diode, Germanium BKC 1N270


D3 414–007 Diode, General Instruments 1N4007

Q5 420–629 Transistor, Motorola MRF629

Q4 424–427 Transistor, Motorola 2N4427 or SGS 2N4427

Q1 440–245–1 Transistor, Motorola 2N2857

24



L11 513–016 Ferrite Bead, #56–590–65/4B

Q4 520–049 Heatsink, Thermalloy 2260R red

J1 550–084 Connector, phono jack Molex 15–24–0503

J2 550–084 Connector, phono jack Molex 15–24–0503

P1 550–197 Connector, 4 dual pin header (cut from 550–316)

PCB 800–163B PC Board, Multiplier RPT–2/15/30 STL–10 REV–9544

PARTS LIST

STL POWER SUPPLY

Item Marti No. Description

10 PER 500–148 Eyelet, GS3–12 GM





C05 219–153 Capacitor,electrolytic 15000uF 25V 159LBA025M2CG

C06 270–103 Cap, Monolithic chip 10000pF 10% XR7 Kemet C1206C103J5RACTR

C07 NOT USED

C08 NOT USED

C09 NOT USED

C10 NOT USED

C10B 270–102 Capacitor,monolithic chip,1000pf 50v 5%KemetC1206C102J5GACTR

C11 NOT USED

C11B 268–102 Capacitor, .001 mf 50v disc –20+80% Pace F5Z5U1C102Z–JT

C12 NOT USED






D1 415–401 Diode, Motorola 1N5402







L1 330–019 Inductor, Fair–Rite #2961666671 STE25C0236–0BW

25

L2 NOT USED

L3 NOT USED

L4 NOT USED

L5 NOT USED

L6 NOT USED

P1 550–138 Connector, 8 pin Molex header (cut from 550–162)

PCB 800–168B PC Board, Power Supply RPT–15 STL–10 REV–9514

R1 145–202–2 Resistor,2K 1% 1/4W Metal Film

R2 101–501 Potentiometer, 500 ohm cermet Bourns 3309P–501

PARTS LIST

STL INPUT FILTER BOARD


2 PER 500–004 Screw, 4–40 x 1/4” phillips pan head M/S Nickel Plated

2 PER 500–162 Screw, 4–40 x 7/16” phillips pan head MS zinc plated

C01 NOT USED

C02 NOT USED

C03 NOT USED

C04 NOT USED

C05 NOT USED







C12 270–220 Cap, monolithic chip, 22 pf 50v 5% KEMET C1206C220J5GACTR





J4 550–170 Connector, D–Sub 15 pin angle Keltron DNR–15PJL–SG

JP1 550–182 Open Top Two Circuit Shunt Molex 15–38–1024

JP1 550–182 Open Top Two Circuit Shunt Molex 15–38–1024

JP1 550–185 Connector, 5 dual pin header (cut from 550–316)

JP2 550–184 Connector, 1 dual pin header (cut from 550–316)

L01 NOT USED

L02 NOT USED

L03 NOT USED

26

L04 NOT USED

L05 NOT USED


L07 330–018 Inductor, 10 uH 1–43LQ105–1

L08 330–018 Inductor, 10 uH 1–43LQ105–1

L09 330–018 Inductor, 10 uH 1–43LQ105–1


L11 330–018 Inductor, 10 uH 1–43LQ105–1

L12 330–018 Inductor, 10 uH 1–43LQ105–1

L13 330–018 Inductor, 10 uH 1–43LQ105–1

L14 330–018 Inductor, 10 uH 1–43LQ105–1

L15 330–018 Inductor, 10 uH 1–43LQ105–1

L16 330–018 Inductor, 10 uH 1–43LQ105–1

P1 550–123 Connector, 10 pin header (cut from 550–162)

P2 NOT USED



PCB 800–193B PC Board, I/O Filter STL–10 R–10 REV–9433

R1 145–122–1 Resistor, 1.2k ohm 1/4 watt 1% CCF07 1.2K 2% TR

T1 NOT USED

TB–1 511–043B Terminal, 2 point w/brackets

PARTS LIST

STL–10 AUDIO BOARD




C03 NOT USED


C05 219–221 Capacitor, electrolytic 220uF 25V radial NIC UVX1E221MPA1TD

C06 219–220 Capacitor, electrolytic 22uF radial 25V NIC UVX1E220MDA1TD



C09 255–100 Capacitor, 10 pf 5% NPO disc Pace F5NPO1C1OOJ–TR

C10 219–221 Capacitor, electrolytic 220uF 25V radial NIC UVX1E221MPA1TD

C11 255–102C Capacitor,102 K X7R Ceramic Dip C322C102K2R5CA

C12 215–202 Capacitor, .002 mfd 2.5% 100v polypro Seacor PFWAB20HGNE

C13 256–131 Capacitor, 130 pf 5% 50V NPO disc Pace F8NP01C131J–Bulk


27

C15 215–301 Capacitor, 300 pf 2.5% 100v polypro Seacor PFWAA300IGTE



C18 215–242 Capacitor, .0024 mfd 2.5% 100v polypro Seacor PFAB240HGUE




C22 NOT USED





C27 NOT USED

C28 NOT USED

C29 NOT USED

C30 299–470 Capacitor, tantalum, 4.7 mf 16v Kemet T350B475K016AS


D2 NOT USED

D3 NOT USED

D4 NOT USED

D5 NOT USED

D6 NOT USED

IC1 400–072 Integrated Circuit, TI TL072CP



P1 550–123 Connector, 10 pin header (cut from 550–162)

P2 550–125 Connector, 5 pin Molex Header (cut from 550–162)

PCB 800–194B PC Board, Audio STL–10 REV–9440

Q1 423–822 Transistor, NTE 459 (replaces Natl 2N3822)






R06 145–124 Resistor, 120k ohm 1/4 watt 5% carbon comp 30BJ250

R07 145–124 Resistor, 120k ohm 1/4 watt 5% carbon comp 30BJ250

R08 145–563 Resistor, 56k ohm 1/4 watt 5% carbon film 29SJ250

R09 101–104 Potentiometer, 100K ohm cermet Bourns 3309P–104


28



R13 145–683–1 Resistor, 68k ohm 1/4 watt 2% RL07S683G


R15 101–502 Potentiometer, 5k ohm cermet Bourns 3309P–1–502







R22 145–912–1 Resistor, 9.1k ohm 1/4 watt 2% RL07S912G






R28 NOT USED

R29 NOT USED







R36 145–222 Resistor, 2.21K ohm 1/4 watt 1% metal film Mepco SFR25

R37 145–152 Resistor, 1.5k ohm 1/4 ohm 1% metal film Mepco SFR25





R42 145–030 Resistor, 3.3 ohm 1/4 watt 1% metal film Mepco SFR25




R46 NOT USED

R47 NOT USED

R48 NOT USED

29

S1 530–053 Switch, slide Alco SLSA–220–1

S2 530–053 Switch, slide Alco SLSA–220–1

PARTS LIST

STL–10/10A/30 450/950 MODULATOR


1 PER 520–041 Clip, transistor, Atlee 100–200–1–2 cad plated

C01 NOT USED


C03 NOT USED





C08 255–271C Capacitor, 270pF 5% 200V ceramic dipped C322C271H2G5CA

C09 255–161 Capacitor, 160 pf 300v 5% silver mica CD10FD161J03

C10 NOT USED

C11 255–270 Capacitor, 27 pf 5% NPO disc Pace F5NP01C270J–TR




C15 255–050 Capacitor, 5 pf 5% NPO disc Pace F5NPO1C5ROJ–JT

D1 410–914 Diode, 1N4148 Philips

D2 410–150 Diode, zener Motorola 1N4744A 15v 1 watt

IC1 800–160–1A

X–Mitter Freq. Control Module

L1 350–044 Inductor, 1.0 – 2 uH w/shield can #47271–022

L2 350–037 Inductor, 13 1/2 turn orange Coilcraft 143–13J12S

L3 330–007 Inductor, 1 uH Delevan #1840–10

M1 800–160–1A


P1 550–125 Connector, 5 pin Molex Header (cut from 550–162)

PART OF800–160–1A

411–404 Diode, Motorola Hyper–Abrupt Tuning SMV–1732

PCB 800–195B PC Board, Modulator STL–10 REV A

Q1 800–160–1A


Q2 420–090 Transistor, Philips BFY90


30

R01 145–241–1 Resistor, 240 ohm 1/4 watt 1% RL07S241G



R04 145–241–1 Resistor, 240 ohm 1/4 watt 1% RL07S241G



R07 104–502 Potentiometer, 5K ohm cermet Spectrol 64Y502 top adjust





R12 145–030 Resistor, 3.3 ohm 1/4 watt 1% metal film Mepco SFR25






TP1 511–038 Terminal, Keystone 1238

Y1 520–040 Crystal socket, CS–109–07

31

PARTS LIST

CONTROLLER BOARD





S1 530–008 Switch, toggle SPDT C&K 7101MYZQ or Apem #5636AB16

P1 550–175 Connector, 5 pin Molex angle header (cut from 550–163)

PCB 800–197B PC Board, Control STL–10 REV 9434

C1 NOT USED

C2 NOT USED

C4 NOT USED

Q1 NOT USED

R1 NOT USED

R2 NOT USED

R3 NOT USED

R4 NOT USED

C7 NOT USED

C6 NOT USED

C8 NOT USED

C9 NOT USED

D01 410–155 LED, Red rectangular #604–L113HDT

PARTS LIST

FEED THRU BOARD STL10/950

PCB 800–268B PC Board, Feedthru STL–10 NO REV











P2 / P4 550–156 Connector, 10 pin Molex header 26–48–4102

P3 / P5 550–156 Connector, 10 pin Molex header 26–48–4102

32

PARTS LIST

STL METER BOARD


M1 030–043M Meter, HS13 VU/Watt (black)

R05 101–502 Potentiometer, 5k ohm cermet Bourns 3309P–1–502

R08 103–502 Potentiometer, 5k ohm cermet Bourns 3309W–1–502





D3 410–113 LED, Yellow rectangular Lumex#SSL–LX2573YD

D4 410–113 LED, Yellow rectangular Lumex#SSL–LX2573YD

D2 410–255 LED, Green rectangular Lumex#SSL–LX2573GD


2 PER 500–004 Screw, 4–40 x 1/4” phillips pan head M/S Nickel Plated

4 PER 500–055 Lockwasher, #4 internal tooth small pattern zinc plated

2 PER 500–133 Screw, 4–40 x 5/8” binding head nickel plated

B1 510–196 Subminiature Lamp, Lumex IFL–LX2162–16T

B2 510–196 Subminiature Lamp, Lumex IFL–LX2162–16T

4 PER 513–022 Spacer, 4–40 x 3/8 hex threaded Keystone 1450B

2 PER 513–033 Spacer, 4–40 x 13/16 hex threaded Concord 535–8413–02

S1 530–059 Switch, rotary 10WA135



P3 550–208 Connector, 3 pin single row header (cut from 550–207)

P3 800–280A STL–10/15 LED Array Board

PCB 800–290B PC Board, Meter STL–15C REV–9504

R1 NOT USED

R2 NOT USED

R3 NOT USED

R4 NOT USED

33

STL–10A SCHEMATICS

Documents

Marti STL-10A.pdf