Technalogix TAU-100 User manual

TAU-100
POWER AMPLIFIER
NEW
ADVENTURES
IN
BROADCASTING
Technalogix

You’ve already unpacked it, haven’t you? You’ve unpacked it and
plugged it in and turned it on and fiddled with the knobs.No?
Okay,good. Please take a few minutes to read the manual and
familiarize yourself with your new Technalogix power amplifier.
We believe that this manual, and of course our equipment, should
be everything you need to get on the air with superb broadcast
quality video. We understand that a capable and confident user
will get the most out of our product and we have made every
attempt to educate readers of all technical levels. If there is
something that is not clear, or you require further information,
please do not hesitate to contact us and we’ll be glad to help out.
Technalogix Ltd.
#4, 8021 Edgar Industrial Place
Red Deer, Alberta, Canada
T4P 3R3
Phone:[phone]
Fax: [phone]
URL: www.technalogix.ca
Email: [email protected]
[email protected]
We truly appreciate that you have chosen us as your television
broadcast system supplier. Happy viewing.

Table of Contents
SECTION I-SAFEGUARDS..............................................................................................I-1
SAFETY AND FIRST AID.....................................................................................................I-2
OPERATING SAFEGUARDS................................................................................................I-3
SECTION II -WARRANTY.............................................................................................II-1
SECTION III -OVERVIEW...............................................................................................III-1
STANDARD FEATURES .....................................................................................................III-1
PRINCIPLE OF OPERATION...............................................................................................III-2
BLOCK DIAGRAM..............................................................................................................III-3
SPECIFICATIONS...............................................................................................................III-5
SECTION IV -RF COMPONENTS................................................................................IV-1
AMPLIFIER PALLETS.......................................................................................................IV-1
SPLITTER/COMBINER.....................................................................................................IV-4
DIRECTIONAL COUPLER.................................................................................................IV-4
ISOLATOR .......................................................................................................................IV-4
FILTER............................................................................................................................IV-4
SECTION V -POWER SUPPLY SECTION......................................................................V-1
SECTION VI-MONITOR AND CONTROL SYSTEM.......................................................VI-1
CONTROL BOARD OVERVIEW (SERIES II-H).................................................................VI-1
POWER SUPPLY COMPONENTS.....................................................................................VI-1
INTERFACE COMPONENTS.............................................................................................VI-2
SIGNAL CONDITIONING COMPONENTS..........................................................................VI-3
DISPLAY COMPONENTS.................................................................................................VI-4
MICROCONTROLLER COMPONENTS...............................................................................VI-5
FAULT SHUTDOWN.........................................................................................................VI-6
REMOTE PORT...............................................................................................................VI-7
BILL OF MATERIALS.......................................................................................................VI-8
SCHEMATICS ................................................................................................................VI-10
SECTION VII -MECHANICAL SECTION.......................................................................VII-1

SECTION VIII -INSTALLATION...................................................................................VIII-1
BUILDING RECOMMENDATIONS.....................................................................................VIII-1
HEATING AND COOLING REQUIREMENTS.....................................................................VIII-2
ELECTRICAL SERVICE RECOMMENDATIONS.................................................................VIII-3
ANTENNA AND TOWER RECOMMENDATIONS................................................................VIII-4
SHELTER SECURITY......................................................................................................VIII-5
UNPACKING AND INSPECTION.......................................................................................VIII-6
LOCATION ANDFUNCTION OFCONTROLS ANDCONNECTORS (TAU-100POWER
AMPLIFIERS)..................................................................................................................VIII-7
LOCATION AND FUNCTION OFCONTROLS AND CONNECTORS (POWER SUPPLY).......VIII-9
INITIAL HOOK UP.........................................................................................................VIII-11
SECTION IX -OPERATING PROCEDURE.....................................................................IX-1
SECTION X-MAINTENANCE AND TROUBLESHOOTING...............................................X-1
TROUBLESHOOTING ........................................................................................................X-2

I-1
Section I -Safeguards
General Safeguards
This section is written as a general guide to keep all 5 fingers on your hand and is intended for those
having previous knowledge and experience with these kinds of equipment. It is not intended to
contain a complete statement of all safety precautions, which should be observed by personnel using
this or other electronic equipment.
DOCUMENTATION -Read, retain and follow instructions before operating the equipment.
There is a lot of useful information in the manual, and besides, we spent a lot of time
writing it!
ENVIRONMENT -To reduce the risk of fire or electric shock, do not expose this equipment
to rain, moisture, or rye and sodas at the company Christmas party. Refer all servicing to
qualified service personnel.
SERVICING -Do not attempt to service this equipment yourself as opening or removing
covers can result in a warm tingly feeling and will void the warranty. Refer all servicing to
qualified service personnel.

I-2
Safety and First Aid
Personnel engaged in the installation, operation, maintenance, or servicing of electronic equipment
are exposed to the hazard of high voltage. It is imperative that all safety regulations and precautions
are consistently observed. Knowledge of first aid procedures is recommended. The following
information is presented as a reference only.
•At all times, avoid placing any part of the body in series between ground and circuit points,
whether power is on or off.
•Dangerous voltage may be present in equipment even though power is off. Do not open the
cabinet. Refer servicing to qualified service personnel.
•It is the duty of all personnel to be prepared to give adequate emergency first aid treatment and
thereby prevent avoidable loss of life.
•There are three principle degrees of burns, recognizable as follows:
•a first-degree burn reddens the skin.
•a second-degree burn blisters the skin.
•a third degree burn chars the flesh and frequently places the victim in a state of shock
accompanied by respiratory paralysis.
•Respiratory paralysis can cause death by suffocation within seconds. It is imperative that the
approved methods of artificial respiration are initiated immediately and continue until the victim’s
breathing is normal.
•A muscular spasm of unconsciousness may render the victim unable to break free of the electric
power. If this is the case, turn the power off immediately.
DO NOT TOUCH THE VICTIM OR YOU MAY SHARE THE SAME
PREDICAMENT.
•If the power cannot be turned off immediately, very carefully loop a dry rope, article of clothing,
length of strong cloth or a rolled-up newspaper around the victim and pull the victim free of the
power source. Carefully avoid touching the victim or clothing.
•Once free of the power source, the victim must be placed in a reclining position and covered
with a blanket or newspapers to keep warm. At the first opportunity, enlist help in
summoning a doctor. If a doctor cannot be summoned, transport the victim to the doctor or a
hospital. Be sure the victim is kept well covered and warm while awaiting professional
treatment.

I-3
Operating Safeguards
It is a known fact that our broadcast transmitters and translators enjoy 50-ohm load impedances.
So much so, that it is imperative you maintain 50-ohm impedances throughout your system. In
return, your equipment will provide you with maximum power transfer to the antenna and
decreased reflected power heading back towards the amplifier pallets, reducing the amount of
magic smoke that gets let out of the power amplifier. Before anything is turned on, ensure that
there is a 50-ohm path from the output of each stage to the input of the next, all the way to the
antenna.
In addition to maintaining proper 50-ohm impedances throughout the signal chain, it is also
important, whenever possible, to make sure the RF drive going to the input of the power amplifier
is removed before turning on or turning off the DC power supply. This is because all of the RF
transistors used in the individual amplifier pallets are fabricated with LDMOS (Laterally Diffused
Metal Oxide Semiconductor) technology. Nice and linear yes, but they do not like to make any RF
power when their supply voltages are not within a specific range. When you first turn your power
amplifier on or off, the DC power supply’s output voltage may take a while to stable out to a safe
operating voltage. Ten seconds wait before applying the RF drive will ensure no issues arise.
Our power amplifiers are designed to reliably generate a specific RF output power. Failing to
adhere to overdriven amplifier warnings can decrease the reliability of your system, and frankly,
makes our repair department busy and grumpy. If you need to transmit to a little larger coverage,
you are better off increasing antenna gain, and more importantly, antenna height above average
terrain. On TV and FM broadcast frequencies, insufficient antenna height puts an upper limit on
your range, regardless of power levels, as the distance from your antenna to the radio horizon is
limited.

II-1
Section II -Warranty
Ourlegaleseis straightforward. It is simply designed to giveyou peace ofmind and helpsyou resist
the temptation to have your electronics friend try to repair your Technalogix product.
Technalogix Ltd. products have been completely tested and found to meet specifications and be in
proper operating condition. They are warranted to be free from defects in materials and
workmanshipfora period of one year from the dateof shipment. If the system becomesdamagedin
shipmentandthereareobvioussignsofdamageto the outside of the packaging, notify your courier
immediately before that courier walks out the door.
Technalogix Ltd. will not be liable for damages of whatever nature arising out of or in connection
with the equipment or its use thereof. Technalogix does not assume responsibility for injury or
damage resulting from the practices of untrained or unqualified personnel in the handling of this
equipment.
Technalogix Ltd. warranty does not include:
•misuse, neglect or accident.
•incorrect wiring and /or improper installation.
•unauthorized repairs, modifications or use in violation of instructions issued by Technalogix.
•incidental or consequential damages as a result of any defect.
•reshipment cost or insurance of the unit or replacement units or parts.
•acts of nature or terrorism.
Technalogix agrees, at our option, to remedy warranted defects or furnish a new part in exchange
foranypart of a unit which, under normal installation,use and service,becomesdefective.Theuser
will pay for transportation costs to and from the repair center.

II-2
To claim your rights under this warranty:
•Contact Technalogix and describe the problem in as much detail as possible. See
troubleshooting section in this manual. If a solution cannot be found at this time, it may be
determined that the unit will have to be returned to Technalogix for repair, once a Return
Materials Authorization (RMA) number is provided.
•Packageequipmentcarefully for prepaid shipment to Technalogix. Includeawritten description
of the problem experienced, a copy of the original invoice establishing warranty status, and the
RMA.
Technalogix reserves the right to make revisions in current production of the equipment and
assumes no obligation to incorporate these changes in earlier models.
Shipping Address:
Technalogix Ltd.
ATTN: RMA#
#4, 8021 Edgar Industrial Place
Red Deer, Alberta, Canada
T4P 3R3
Ph: 403.347.5400
Made in Canada, returned for repairs

III-1
Section III -Overview
Standard Features
•No sync compression to ensure power amplifier is digital compatible
•Narrow output bandpass filter allows adjacent channel operation
•Front panel Liquid Crystal Display (LCD) to monitor forward and reflected RF power, and DC
voltage
•Microcontroller-based monitoring and control ensures amplifier will never be overdriven and high
VSWR will not damage amplifier
•AC circuit breaker on back panel to eliminate replacement of fuses
•RF/EMI filtering on AC entry plug
•All aluminium enclosure maintains power amplifier’s light weight
•3U-high enclosures for 25 and 100 watt power amplifiers reduce rack space
•Simple design using commonly available parts ensures reliable operation
•Predominate and third-order intermodulation distortion exceeds Industry Canada and FCC
specification.

III-2
Principle of Operation
The TAU-100poweramplifiersuppliesa 100 watt peak video signalwith10%auralpower on any of the
UHF television channels 14 through 69. Please note that channel selection must be made at time of
order, as the transmitter or translator is calibrated and tested to the channel requested and is not field
tuneable. The TAU-100 power amplifier is a modular solid-state 100-watt broadcast amplifier utilizing
readily available RF components wherever possible, thus enhancing the serviceability of the
equipment.
The TAU-100 is comprised of aUHFTV-10 driver andUHFTV-150 final amplifier. The unique zero sync
compression technology ensures digital ready operation.
The TAU-100 features ultra linear amplification and individual channel RF output bandpass filtering.
The amplifier modules are stable for high reliability and long service life.

III-3
Block Diagram
The RF signal enters through the RF Input connector on the power amplifier enclosure from the
modulator or processor. It then passes through an RF attenuator to limit the output power level of
the power amplifier and to help buffer any transients that may come into the power amplifier. After
attenuation, the signal is amplified through the UHFTV-10 driver and UHFTV-150 T final pallets
before the signal passes through an isolator (circulator with load) and a bandpass filter. Finally, the
amplified signal passes through a dual directional coupler for monitoring purposes. After the
directional coupler, the signal exits the power amplifier enclosure before heading out to an antenna
for broadcast.

A=+12dB min.A=+26dB min. A=-0.1dB
A=-0.3dB
To Wattmeter
and Antenna
A=-0.2dB typ.
UHFTV-150
UHFTV-10
RF OUTRF INPUT
VV
COUPLER
DIRECTIONAL
V
CIRCULATOR
FILTER
TERMINATION
50-OHM
ATTENUATION
TAU-100 Block Diagram
Date: May 24, 2005 Page: 1 of 1
Rev ID

III-5
Specifications
The following specifications were taken with a Technalogix modulator/processor. Should a different
modulator or processor be used, specifications could vary. For this reason, we recommend that any
different modulator/processor be shipped to Technalogix so the system can be matched and set up
optimally. In addition, the audio/video ratio the input to the power amplifier needs to be–10 dB in order
for the software and LCD readout to be accurate.
RF Characteristics
Frequency range any specified UHF Channel 14 to 69
Frequency Response (one channel) ±0.5 dB
Frequency Stability ±250 Hz
Selectivity 60 dB (adjacent channel)
Minimum Input Level 0 dBmV
Rated Visual Output Power 100 Watts
Rated Aural Output Power 10% of peak visual power
IF Output Level+35 dBmV nominal
Input Impedance 75 Ohms
Output Impedance 50 Ohms
Harmonics > 60 dB below rated power
Predominant Intermodulation Distortion dBc = decibels below visual carrier
+ 920 kHz > -50 dBc
-920 kHz > -50 dBc
+ 2.66 MHz > -50 dBc
-2.66 MHz > -50 dBc
+ 5.42 MHz > -50 dBc
+ 7.16 MHz > -50 dBc
3rd Order Intermodulation Distortion
+ 4.5 MHz > -60 dBc
+ 9.0 MHz > -60 dBc
All others > -60 dBc
Spurious Emissions > -60 dBc
NTSC Video Characteristics
Input Level to modulator (for 87.5% modulation) 1.0 VPP
Differential Phase (at 87.5% modulation) ±2 Degrees
Differential Gain (at 87.5% modulation) 2%
Group Delay < ±40 nS
Video Group Delay Pre-emphasis Conforms to IC/FCC specifications
K-Factor 1.9% for 2T Pulse
Hum and Noise > 60 dB below rated power

III-6
Aural Characteristics
Input Level for 25 kHz Deviation 0.3 VPP
Frequency Response (Standard Pre-emphasis) ±1 dB
Harmonic Distortion (25 kHz Deviation) < 1% 50 Hz to 15 kHz
Amplitude Modulation Noise > 50 dB
Frequency Modulation Noise > 60 dB
Intercarrier Stability ±250 Hz
Physical Characteristics
Power Requirements 100-130,210-230 vac, 50/60 Hz
Operating Temperature 0 -50°C
Dimensions (power amplifier only) W-19”,D -21 ¼”, H-5 ¼”, 3U-high

IV-1
Section IV –RF Components
Amplifier Pallets
The UHFTV-10 pallet is a two stage ultra linear class-A linear pallet. It has a minimum gain of 38dB and
draws no more than 2.75Adc total drain current (the exact bias and drain currents of yoursystem are
found in the spec sheet supplied with each manual). The quiescent and drain currents can be
measured on the UHFTV-10 pallet by measuring the voltage drop across the current sense resistor
found directly at the DC power supply lead input to the pallet. This resistance is 0.01-ohms,providinga
10mV per ampere ratio.
The UHFTV-150 pallet used in the driver and final amplification stages use LDMOS (Laterally Diffused
Metal Oxide Semiconductor) technology. LDMOS technology offers higher gain, efficiency and linearity
over standard MOSFET and Bipolar devices. LDMOS transistors have the added advantage of not
having BEO (Beryllium Oxide) in their construction. These pallets are split into (2) frequency bands
based on the channel ordered (channels 14-38 and channels 33 to 70). The UHFTV-150 amplifier
pallet have a typical gain of 14dB and draw no more than 16Adc (again, the exact bias and drain
currents of your system are found in the spec sheet supplied with each manual). Currents for these
pallets must be measured with an ammeter in series with the power supply lead. Temperature
compensated biasing helps ensure steady operating levels over wide temperature ranges.
Each of the amplifier pallets is connectorized. All amplifier pallets must have the transistor drain
voltages reach at least 26Vdc before the RF drive is applied.

IV-4
Isolator
The power amplifier pallets are protected in part by the isolator located in the filter enclosure. It is
actually made up of a circulator and 50-ohm dump resistor. The circulators’ specifications include an
insertion loss of less than 0.2dB with an isolation rating better than 20dB. Any reflected power gets
dumped into the flanged power resistor. This way, there is instantaneous protection due to the isolator
setup and long term protection due to the software.
Filter
The passive bandpass filter rejects spurious and harmonic output products and passes the UHF
channel RF output. The cavity resonator uses aperture coupling. Typical insertion loss is 0.3 dB to 0.6
dB depending on channel frequency. Average roll off is –33 dBc at a point 4.5 MHz below the peak
visual carrier frequency and–30 dBc 9.0 MHz above the peak visual carrier frequency. The filter is DC
grounded on both the input and output for additional lightning protection.
Directional Coupler
The Technalogix dual directional couplers provide DC voltages proportional to forward and reflected
RF power monitoring. These analog voltages are converted for processing using a 10-bit analog to
digital converter. Themicrocontrollersystemmonitors power supply voltage,forwardandreflected RF
power, amplifier module temperature, the input video signal and the “VIEW” display request button.
The LCD is based on the industry standard HD44780 controller and contains 4 lines with 20 characters
per line. The LCD communicates with serial-to-parallellatcheson the monitor andcontrolcircuit board
and the latches communicate with the microcontroller via a custom serial interface.

V-1
Section V –Power Supply
Switching AC-DC power supplies are used to power the amplifier pallets, the control circuits, and all of
the fans. There is (1) power supply used to generate the necessary current for the amplifier pallets,set
to 28.3 Vdc nominally.
The power supply is a Mean Well SP-500-27. This switching power supply is fully protected against
short circuit and output overload. Short circuit protection is a cycling type power limit. The internal AC
fuse is designed to blow only on a catastrophic failure in the unit–the fuse does not blow on overload
or short circuit. The thermal shutdown automatically recovers when the power supply chassis cools
down.
AC (115Vac) is fed into the enclosure via a filtered EMI AC entry. It is then current limited with a
resettable circuit breaker before passing through a rocker switch. This switch turns the AC on and off
to the switching power supply.