ETG2000.20 ETG1000.10 ETG500.5 ETG150 ETG 20 FM SOLID STATE TRANSMITTER WITH AUDIO CHANGEOVER OPTION Rev. 01 − 26/06/2018 Cod.
All copyrights are reserved, you may not reproduce any part of this manual, in any form, without the express written permission of Elenos S.r.l.
Revision history no.
Index 1 2 3 4 4 Informative letter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 1.1 Personnel in charge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 1.2 Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 1.3 Exclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 1.4 Exemption from liability . . . . . . . . . .
Index 5 6 7 8 4.3.1.3 Safety Management (“Lifextender”)R . . . . . . . . . . . . . . . . Block diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1 Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1.1 ETG 2000.20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1.2 ETG 1500.15 / ETG 1000.10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Index
1 Informative letter Informative letter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1 Personnel in charge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2 Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3 Exclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.4 Exemption from liability . . . . . . . . . . . . . . . . . .
1.1 Personnel in charge This manual has to be intended as an integral part constituting the equipment, and must be readily at hand to all the personnel responsible for its installation, use and maintenance.
1.
Informative letter
2 Safety Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.1 Safety precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2 First aid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2.1 Treatment of electrical burns . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2.1.1 Extensive burns and skin cuts . . . . . . . . . . . . . . . . . . . 2.2.1.
Safety
All ELENOS s.r.l products are compliant with the safety standards required for this type of equipment. 2.1 Safety precautions The user must follow also the safety precautions listed below: D The original configuration of the equipment must absolutely not be modified. On receipt of the same equipment it is essential to check whether the supply is compliant with the order’s specific terms and in case of nonconformities please report it immediately Elenos Srl.
The equipment is directly connected to the “building installation” Between the equipment and the “building connection” there is an interposed structure D To ensure a correct use of the equipment do not obstruct the ventilation grids. Do not put the equipment close to heat sources, flammable products, or inside closed installations lacking of a proper air circulation. D It is required to observe general and firefighting rules for the place hosting the equipment.
2.2 First aid This paragraph does NOT represent a complete guide about first aid procedures, it is rather intended as a brief summary to be used as a reference. It must be in fact an impelling duty for all the personnel operating with this equipment to be capable of performing appropriate first aid procedures in order to prevent avoidable deaths. 2.2.1 Treatment of electrical burns 2.2.1.1 Extensive burns and skin cuts D Cover the area with a clean sheet or cloth.
fig.c1 fig.c2 C) Circulation (fig. c1): D check the victim’s pulse (fig. c1) D if absent, start cardiac massage (fig. c2) D compress the chest every 1.5 − 2 seconds D if a rescuer is present, perform 15 compressions in approximately 80 seconds, + 2 quick blows D if there are two rescuers, perform 5 compressions in approximately 60 seconds, + 1 quick blow (fig. c3) WARNING: Do not interrupt the rhythm of compressions when the second person is performing artificial respiration. fig.c3 2.2.2.
Provide a protected under load disconnector (circuit breaker or fuses) with appropriate disconnection power and capacity according to the absorption characteristics of the equipment model. Use cables of an appropriate size with respect to the rated absorbed current. Earth connection must be performed according to the applicable laws. Special care must be applied to the earth connection of the antenna system since it is exposed to electrical atmospheric events.
2.4 Exposure evaluation Exposure assessment requires the identification of electric field values in places where the presence of people may occur. The field values must refer to the type of stay and the exposed subjects, according to the provisions of current legislation. The identification of the electric field values can be carried out in various ways, depen ding on the need for precision and the fact that one intends to perform a prediction, or a subsequent verification.
In the specific case of broadcasting plants for sound and television broadcasting, the following recurrent characteristics can be found: a. the source is not isotropic, so the ERP should be calculated in the direction of the evaluation point b.
2.4.1.1 Electric field values (V/m) as a function of power (W) and distance. Power transmitted by the source (ERP) in Watts Distance from the source of the evaluation point 30m 98.4ft 50m 164ft 100m 328ft 300m 984ft 500m 1,640ft 1,000m 3,280ft 3,000m 9,840ft 1.864mi 5,000m 16,400tf 3.107mi 10,000m 32,800ft 6.214mi 1 0.18 0.11 0.05 0.02 0.01 −− −− −− −− 30 1.00 0.60 0.30 0.10 0.06 0.03 −− −− −− 50 1.29 0.77 0.39 0.13 0.08 0.04 0.01 −− −− 100 1.82 1.09 0.55 0.18 0.
3 CE conformity CE conformity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.1 CE conformity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2 Labels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2.1 Identification label . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2.2 Assistance label . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Safety
3.1 CE conformity For fi rst immission on the market, ELENOS s.r.l respects the procedures envisaged by the 1999/5/EC Directive. This includes the following: D Technical documentation available exclusively to the Control Authority for 10 years after the launch on the market of the last equipment produced for that type. Such documentation contains the product description, the drawings, the electrical diagrams, circuits, etc.
CE conformity
CE conformity 25
3.2 Labels 3.2.1 Identification label It shows the key features equipment, such as: manufacturing company, product model, power supply type and power consumption. Warning: do not ever remove this label. 3.2.2 Assistance label It shows the main Elenos customer assistance contacts. ! Note: this label may not be present. 3.2.3 Warranty label Unauthorized removal or tampering of this seal (positioned over the screws) will make void the warranty. 3.2.
4 Product description Product description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1 Controls and connections overview . . . . . . . . . . . . . . . . . . . . . 4.2 Contnectors pin assignment . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.1 EIA485 − Telemetry − Ethernet − Interlock . . . . . . . . . . . . . . . 4.2.2 TC/TS − Profiles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.3 Stereo L/R − AES/EBU . . . . . . . . .
Product description
4.1 Controls and connections overview Below, the list of connections and controls available in all the product line. The differences between the two rear panels shown, concern only the number of fans and the type of RF output connector.
4.2 Contnectors pin assignment 4.2.1 EIA485 − Telemetry − Ethernet − Interlock EIA485 (DB9) − Cn no. 21, 2 Pin. # Function Note 1 Tx+ EIA485/422 2 Tx− EIA485/422 3 Rx+ EIA485/422 4 Rx− EIA485/422 5 Common Gnd (frame) 6 Common Gnd (frame) 7 Common Gnd (frame) 8 Common Gnd (frame) 9 Common Gnd (frame) Ethernet Connect. (EJ45) − Cn no. 19 Pin. # Function Pin Function 1 TD+ 5 TCT 2 TD− 6 RD− 3 RD+ 7 n.c. 4 n.c. 8 RCT Interlock Connector − Cn no. 20 Pin.
4.2.3 Stereo L/R − AES/EBU Stereo L/R (XLR) − Cn no. 11 Pin. # Function Type Note 1 Common Gnd // 2 Input L/R + Bal. 600Ω/10kΩ 3 Input L/R − Bal. AES/EBU (XLR) − Cn no. 14 Pin. # Function Type Note 1 Common Gnd // 2 Input + Diff. 110Ω 3 Input − Diff. 2 1 3 4.2.4 Aux1 − Aux2 − MPX − MPX Monitor Aux1 + Aux2 − Cn no. 12, 10 Pin. # Function Type Note 10kΩ 1 Input Unbal. 2 Common Gnd // MPX Monitor − Cn no. 15 Pin. # Function Type Note 10kΩ 1 Input Unbal. 2 Common Gnd // Pin. # 1 2 MPX − Cn no.
4.3 Safeness algorithms The apparatus is provided with a hardware and software protective system which is partly integrated and partly optional. 4.3.1 Software’s protections 4.3.1.1 IPF (Intelligent Proportional Foldback) The IPF is an intelligent system which reduces the equipment’s output power in case of excess of load mismatch, thus preventing the equipment turning off. Foldback acts if the load mismatch increases slowly.
Current Management on the power supply (Lifextender)R This is activated when the maximum current rated for continuous operation of the power supply is exceeded. This value is lower than deliverable current limit and represents the threshold which can be exceeded only for short periods (maximum 1 minute each time).
Product description
5 Block diagrams Block diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1 Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1.1 ETG 2000.20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1.2 ETG 1500.15 / ETG 1000.10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1.3 ETG 700.7 / ETG 500.5 / ETG 300.3 / ETG 150 . . . . . . . . . . . . 5.1.3 ETG 20 . .
Block diagram
5.1 Block diagram 5.1.1 ETG 2000.20 FINAL STAGE 2−WAY FM 3−WAY COMBINER 3−WAY FM SPLITTER DRIVER RF IN L. P. FILTER & DIR. COUPLER VCO RF OUT RF SECTION CPU board MAINS INPUT 220VAC (on rear panel) DRIVER MODULATOR FINAL L. P.
5.1.2 ETG 1000.10 FINAL STAGE 2−WAY FM COMBINER 2−WAY FM SPLITTER L. P. FILTER & DIR. COUPLER RF IN RF OUT RF SECTION MAINS INPUT 220VAC CPU board (on rear panel) FINAL −12 VDC SWITCHING +5 VDC PWR SUP +12 VDC +13 VDC DC/DC CONV AC/DC CONV AUX VDC +30/40VDC POWER SUPPLY SECTION 38 Block diagram L. P.
5.1.3 ETG 700.7 ETG 150 MAINS INPUT 220VAC ETG 500.5 ETG 300.3 CPU board (on rear panel) RF AMP MODULATOR L. P. FILTER VCO RF OUT RF MONITOR −12 VDC SWITCHING +5 VDC PWR SUP +12 VDC AC/DC CONV VDS POWER SUPPLY SECTION 5.1.4 ETG 20 MAINS INPUT 220VAC CPU board (on rear panel) RF AMP MODULATOR VCO L. P.
Block diagram
6 User instructions User instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1 User interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1.1 Menu tree . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1.2 TX Control Panel (Main Window) . . . . . . . . . . . . . . . . . . . . . . . . . 6.1.3 System Menu ! System Config (1 of 2 and 2 of 2) . . . . . . . . . . 6.1.
Managing the device in local mode. Navi gating the menus and setting the para meters. Status LEDs and messages. Messaging. The equipment can send messages regarding status, events and alarms. The list can be consulted locally on a display, remotely via PC connected in telemetry to the front panel or via web. Here is the complete list. Devices that can be connected to the equipment. For remote controlling via web, see the manual dedicated to the web interface.
6.1 User interface All commands and data displayed by screen are listed on next pages. Warning: The screens shown below are subject to change without notice and may look some different depending on system configuration. Note: for information about the remote control via web interface, please refer to the relevant “WEB interface User Manual” LOCAL REMOTE To navigate the entire menu by encoder the equi pment has to be set in Local Mode.
6.1.1 Menu tree TX CONTROL PANEL SYSTEM MENU MAIN WINDOW 1 SOLUTION LOCAL REMOTE INPUTS MENU 2 RF & POWER MENU 3 PASSWORD MENU 4 D To scroll the menu, rotate the encoder. ALARMS MENU D To enter a submenu, or to access the masks, press it. D To return to the main menu, press and hold the encoder. D The menu is fully accessible only when the unit works in local mode. 5 D Some menu items may not be displayed when the unit works in remote mode.
6.1.2 TX Control Panel (Main Window) Main settings Target power Operating frequency Main levels VU meter area (*) Forward power Reflected power Target audio level (L) Target audio level (R) (*) The number of bars displayed depends on the type of input selected. Up to three bars can be shown: MPX (M), Left Stereo (L) and Right Stereo (R).
6.1.3 System Menu ! System Config (1 of 2 and 2 of 2) SYSTEM MENU Please, note that when a field name is abbreviated in the mask, it will write like this: ShowDisplay = Show D. Temperature Unit: CELSIUS or FAHRENHEIT. Show Display: ALWAYS = display on also in remote mode. Power Oscillation Check: TRUE = RF power swing protection active. UPS Target (W): Target power in case of functioning with UPS. Minimum Temperature Sensors: Failure when >nn broken thermal probes.
6.1.4 System Menu ! Communication Port Set / System Info SYSTEM MENU Front and rear RS485 communication ports speeds and addresses. Currently, default speed values are 38400. Previously, they were 9600. All devices working in combined or n+1 systems must be set to the same communication speed, otherwise they won’t work properly. Default address values are 0.
6.1.5 System Menu ! System Time / Clock Pwr Target 1 of 2 SYSTEM MENU In this screen it’s possible to set the current date “dd/mm/yy” and the current time “hh:mm:ss”, together with the day of the week “wd”. It’s important to set all the parameters correctly to make the adjustment algorithms work well. The line labeled “C” shows the current values, the one with the word “SET>” is editable and accepts the new data. ! SYSTEM MENU The “Target Power Mode” may be “FIXED” or “CLOCKED”.
6.1.6 System Menu ! Clock Pwr Target 2 of 2 / Telemetry Config SYSTEM MENU Here it’s possible defining the power profiles for hours and days of the week. Each hour can be associated to any target available (T3 to T0), defined at the previous step. When “T0” is selected, no bar will be displayed. To copy the current profile to the next day one, force to “T” the value of “Copy over next day:” by pressing the encoder on it. The day for the which the data are inserted is shown by “Target power on day of”.
6.1.7 Inputs Menu ! Base Band Levels / Change Over Inputs INPUTS MENU Display−only screen. Values of the inputs and deviation for the carriers are shown. This mask may look different depending on the equipment operating mode. Displaying VU−meter style bars, located on the right of numeric values, facilitates the evaluation of the parameters. INPUTS MENU The “Exchange” mode may be “AUTOmatic” or “MANUAL” (in this case the equipment must be controlled by the user).
6.1.8 Inputs Menu ! Input Sensitivity Settings INPUTS MENU “Audio Mode” & AUTO sts The option “Left = Right:” set to “TRUE” forces both L and R Stereo inputs to the same attenuation level, otherwise each stereo channel is attenuated by the level stored in “LeVel R” and “LeVel L”. “PreEmphasys” may be 0, 25, 50 or 75 mS. “Aux1(%):” and “Aux2(%): ” specify the attenuation levels of the aux channels input. “Pilot Level (%):” and “Pilot Phase:” specify the percentage of pilot tone and its phase in degrees.
6.1.9 RF & PWR Menu ! View TX Parameters (1 of 2 and 2 of 2) RF & PWR MENU Display−only screen. The following data are grouped here: (On the left) operating frequency; selected profile; deviation level; device efficiency; counter of ROS protection occurred; working hours (on air) and fan working hours. (On the right) target, forward and reflected power; total current absorbed by RF amplifier modules and cooling fans; Vds and max temperature of all internal probes. RF & PWR MENU Display−only screen.
6.1.10 Password Menu ! Password / Password Setting PASSWORD MENU Factory preset password is “0000”. This value must be changed in “Password setting” by system administrator in order to prevent unauthorized accesses. There are two levels of protection: “User” and “System”. Once the settings the two new passwords, access to menu items and parameter changes will be governed by individual privileges. Follow the procedure below. PASSWORD MENU First, change the value of password “USER” (password “SYS.
6.1.11 Password Menu ! Password Recovery PASSWORD MENU If users forgot the password, it’s kindly advised to contact Elenos. The ”UNLOCK CODE” is useful to obtain the 24h “PASSWORD RECOVERY” and must be provided to Elenos. Subsequently, system administrator have to redefine passwords by “PASSWORD SETTING” mask.
6.1.12 Alarm Menu ! Alarm List / Event History ALARMS MENU Display−only screen. It’s possible scrolling the list of all recently occurred alarms. The ones preceeded by letter “A” are active, the others are occurred. Between brackets, the type of message is specifyed: Status,Warning and Alarm. In order to understand the meaning of the alarms please see the paragraph “Alarms/ events listing”. ALARMS MENU Display−only screen.
6.1.13 Alarm Menu ! User Alarm Data / User Alarms Timers ALARMS MENU Parameters of some alarms may be customized. They are: Environmental Temperature (C or F); RFTemperature (C or F); RFCurrent(A); PSU Temperature(C or F); PSU Current(A); Forward power(W) and Reflected power(W). Forcing to “T” the value of “Enable” by pressing the encoder, the alarms will be activated depending on limits specified by “Max” and “Min” values.
6.1.14 Alarm Menu ! Audio Trim and Alarms ALARMS MENU In the box on the right, at the top of the screen, model of board and firmware installed are indicated. This mask summarizes some parameters already seen in “Input sensitivity settings” and “Change over inputs” screens. In addition, the status of the “No Audio Fault” alarm is displayed. Signal management takes place via the TC/TS connector.
6.1.15 Diagnostic Menu ! UART 0 Info / UART 1 Info DIAGNOSTICS MENU Display−only screen. This screen shows the status of the serial communication with the Hostlink Slave and the number of errors that occurred from the beginning. DIAGNOSTICS MENU Display−only screen. This screen shows the status of the serial communication with a terminal monitor or an external GSM modem, along with the number of errors that occurred from the beginning.
6.1.16 Diagnostic Menu ! UART 2 Info DIAGNOSTICS MENU Display−only screen. This screen shows the status of the serial communication with the power supply units and the number of errors that occurred from the beginning.
User instructions
6.2 Alarms/Warnings/Status list A task called “Alarms Managing” monitors all physical and logical quantities. Each of them is sampled and processed by a combinatorial network to evaluate if an alarm (or a warning) must be activated. This task and the ALC management have the same high priority for having a constant monitoring of the entire apparatus and intervene quickly. The last alarms occurred are stored in a list with the time and date of the occurrence.
List of events that may be reported by the equipment. They are of 3 kinds: “STATUS” = possible statuses of the machine; “WARNING” = reports not requiring immediate technical intervention; “ALARM” = faults requiring repair. Some may be different depending on equipment (see brackets in “Message”). Event Code Description 000 CORRECT WORKING No error. The apparatus is working correctly. The event “019 ON AIR” has a higher priority. 001 SYSTEM RESET The list of occurred alarms is under deleting process.
Event Code Message Description 023 PSU LOW POWER One or more PSU are in thermal derating so that the RF output power is reduced. 024 PSU RF OFF The RF section has been turned off so that the fans can quickly cool the apparatus. 025 026 027 028 029 WORKING MODE COMBINED SWR FOLDBACK UNLOCK EXCITER COMM ERROR NO AUDIO 030 OVER 2/3 CARRIER 031 FAN 1 ERROR 032 033 OVER MODULATION FAN 2 ERROR The apparatus works in a combined Tx.
Event Code Description 052 PSU MAINS OVER VOLTAGE 053 PILOT PWR GOOD (Amplifier) The RF input power level is correct. 053 EXT REF MISSING (Exciter) External reference (10Mhz) absent. 054 INCREASE PILOT PWR (Amplifier) The RF input power level is to low but not dangerous and must be increased. 054 MPX NO AUDIO (Exciter) The MPX input level has remained lower than the minimum set level for the set time.
6.3 External connectable devices 6.3.1 Connecting to a LAN/PC Connect the apparatus to PC via LAN using a switch or any other device such as a router. Also the direct connection between apparatus and PC is possible. See web connection manual for all details.
6.3.
7 Datasheet 67 68 70 71 71 72 72 73 74 YY.Y Datasheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.1 Datasheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.1.1 Individual models specific parameters . . . . . . . . . . . . . 7.2 ETG models layouts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.2.1 ETG 2000.20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.1 Datasheet GENERAL DATA Rated output power Operating band Samples RS232/485 Displayable parameters Adjustments Number of RF power LDMOS RF power technology (by Elenos) Number of power supplies Dimensions (rack units/ W−H−D) Weight Cooling fans (long life, speed controlled) Overall efficiency (typical) See “Spec” table, Rated FWD column 87.
Asynchronous AM S/N unweighted Synchronous AM S/N unweighted Modulation frequency range Amplitude/frequency characteristic Stereo crosstalk Distortion Intermodulation distortion Emission class Stereo emission PLL lock time Intermodulation distortion Frequency deviation Maximum frequency deviation Frequency stability RF frequency steps Phase response Modulation capability > 55 dB > 50 dB 16 Hz − 15 kHz $ 0.
7.1.1 Individual models specific parameters “SPEC” table in datasheet 70 Model Rated FWD Weight Consumption Current ETG20 20 adjustable 1 7.9 kg (17.4lb) 60W 0.26A @ 230Vac ETG150 150 adjustable 1 9.4 kg (20.7lb) 230W 1A @ 230Vac ETG300 300 adjustable 1 9.4 kg (20.7lb) 430W 1.9A @ 230Vac ETG500 500 adjustable 1 9.4 kg (20.7lb) 570W 2.5A @ 230Vac ETG700 700 adjustable 1 9.4 kg (20.7lb) 800W 3.9A @ 230Vac ETG1000 1000 adjustable 2 13.2 kg (29.
7.2 ETG models layouts 7.2.1 ETG 2000.
7.2.2 ETG 1500.15 ETG 1000.
7.2.3 ETG 700.7 ETG 500.5 ETG 300.
7.2.
8 Maintenance Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 8.1 Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 8.1.1 Periodic checks and replacements . . . . . . . . . . . . . . . . . . . . . . . .
8.1 Maintenance 8.1.
