TRENDnetメーカーTVP- 221Hの使用説明書/サービス説明書
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TVP-221H User’s Guide FCC Notice This equipment has been tested and found to comply with the lim its for a Class B digital device, pursuant to Part 15 of FCC Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a comm ercial environment.
TVP-221H User’s Guide 3 How to Use This Manual This manual was designed for the non-technical users of the VoIP Gateway (TVP- 221H). It contains information about the functions of the TVP-221H and instructions for its installation, basic configuration and operation.
TVP-221H User’s Guide 4 Documentation Abbr eviations Throughout this guide, the user will come across a number of abbreviations that are common throughout the industry.
TVP-221H User’s Guide 5 Notation Conventions Throughout this guide, different type styles and characters are used. These serve a variety of purposes as described below: Convention Description boldface Commands and keywords are in boldface. italic Arguments for which you supply values are in italics.
TVP-221H User’s Guide 6 Table of Contents How to Use This Manual ......................................................................................................... .3 Important Safety Instructions .............................................
TVP-221H User’s Guide 7 3.2 ATPM ........................................................................................................................... 16 3.3 Destination .........................................................................
TVP-221H User’s Guide 8 Comm on Parameters ............................................................................................................. 3 7 Total Time .................................................................................
TVP-221H User’s Guide 9 6.1 Port Configuration ...................................................................................................... 77 Application 1: Special FXS Connections .........................................................
TVP-221H User’s Guide 10 Chapter 1 Overview This chapter gi ves an overview of the 4 ports deskt op version VoIP Gateway (TVP-221H) and a detailed descript ion of its front panel and rear panel.
TVP-221H User’s Guide 11 1.3 Package Content s The contents of your product should cont ain the following item s: • TVP-221H V oIP Gateway 4 port desk top version • 100-240V Power Adapter • 9-pin straight through RS-232 cable • Printed Quick Installation Guide • User ’ s guide (CD) • RJ45 Cable 1.
TVP-221H User’s Guide Indicator Color Activity Indication PWR Green On Power is supplied to the gateway . SYSTEM Green Blinking The system is running. (Heartbeat LED) LAN ACT 100M LNK COL Green Green Green Green On On Off On On Data is being transferred on the LAN.
TVP-221H User’s Guide 13 LAN / Console Ports The TVP-221H is equipped with an Ethe rnet interface with 10/100 Mbps auto- negotiation, auto MDIX capability. The Et hernet interface port is located on the rear panel. In addition to the Ethernet interface port, there is a 9-pin RS-232 interface port on the rear panel.
TVP-221H User’s Guide 2 Chapter 2 Installing the TVP-221H This chapter gives informati on on how to install the TVP-221H. 2.1 Network Requirement s For the TVP-221H to successfully operate in your network, your network must meet the following requirements: 1.
TVP-221H User’s Guide 15 you do not have to worry about the cable. Any Cat 3 or 5 cable will be sufficient. Once Internet Access has been set up, di sconnect the TVP-221H from configuring PC and connect it directly to your ADSL Cable Modem or place it under a router as configured.
3 Chapter 3 TVP-221H Telephony Concepts The TVP-221H enables the transmission of voi ce and fax traffic over any IP network by digitizing voice and fax signals, encapsulating the information within IP packets, and then sending the packets across the IP network 3.
TVP-221H User’s Guide 17 destination for the call is the telephony port where the call terminated. For calls initiated from telephony ports, the TVP-221H forwards the call to a remote TVP- 221H/TVP-221H via IP network, and the remote TVP-221H/TVP-221H terminates the call.
TVP-221H User’s Guide 18 • Address table sample: Address Entry Hunt Grp_Id Min. Digits Max. Digits Prefix strip Prefix Address 201 3 3 3 3 None 301 4 3 3 3 None 8 1 3 3 0 None 0 1 1 1 0 None 20 11 5 5 2 None 3.52 Hunt Group Table The hunt group table maps a hunt group to a list of destinations.
TVP-221H User’s Guide 19 tone to the PSTN. This method in which the TVP-221H handles DTMF tone is so called DTMF relay. The TVP-221H handles DTMF relay per H. 323 specifications. Certain third party VoIP devices may handle DTMF relay per IMTC standard.
TVP-221H User’s Guide 4 Chapter 4 Configuring TVP-221H from a Web Browser This chapter explains procedures for confi guring the TVP-221H from a web browser. 4.1 HTTP setting mode This section describes the processes for setti ng up the VoIP Gateway once it has been installed.
TVP-221H User’s Guide 21 5. On the IP Address table, enter values as follows: • Specify an IP address set ON. • IP Address : 192.168.0.2 • Subnet Mask : 255.255.255.0 Restart your PC and Start your WEB browser. 6. In the Address box, enter the following: HTTP://192.
TVP-221H User’s Guide 22 Main Menu Function Briefings Home View System Status H.323 Configuration Set H.323 Parameters Dial Plan Settings Links to dial plan setting / entry / store / clear / restore pages. You should complete the dial Plan work sheets before working in this menu.
TVP-221H User’s Guide 23 System Status Select Home In order to view the System Status page, please navigate to Home. The System Status page will display the following parameters: Firmware Version • TVP-221H VoIP Gateway Version: • Boot Loader Version: • RTOS Version: • H.
TVP-221H User’s Guide Fixed IP – Connection Details If you are using a Fixed IP, you are eit her using a fixed IP as assigned by your ISP or your System s Administrator. Please ent er your Fixed IP as designated by your ISP along with Subnet Mask and Default Gateway.
TVP-221H User’s Guide 25 DHCP Client If you will be using the DHCP with a DHCP serv er on your local LAN 1. Select Yes 2. Click on OK 3. Click on Reboot for changes to take effect PPPoE If you will be using the PPPoE as assigned my your ISP 1. Select Yes 2.
TVP-221H User’s Guide 26 Dynamic DNS It allows Internet users to connect to your gateway using a static URL, rather than an IP Address. This is particularly useful because a dynamic IP address, by definition, is constantly changing m aking it difficult for internet users t o find you.
TVP-221H User’s Guide Data - Dynamic DNS Screen DDNS Service DDNS Service You must register for t he service at dyndns.org. Apply for a Domain Name, and ensure it is allocated to you. Details of your DDNS account (Name, password, Dom ain name) must then be entered and saved on t his screen.
TVP-221H User’s Guide H.323 Parameters For the most part end users will not be using these functions / features and / or should use the default settings. For more information please see the Advanced User Manuals or consult with your Systems Integrator 1.
TVP-221H User’s Guide 7. NAT Call Mode : Enables calls from remote sites which use NAT routers with private IP networks behind, default is on 8. Default DTMF Mode : H323 V2 Signal or IMTC. The default is H323 V2 Signal 9. DNS IP Address 10. Alternate DTMF IP Address 11.
TVP-221H User’s Guide 30 iii. Manual: Enables gatekeeper co-operation in manual operation (the gatekeeper address must be properly assigned). The following fields must be filled in when Gate Keeper Mode is set to manual. 2. Gate Keeper Address : Specify the gatekeeper address when configured to manual mode.
TVP-221H User’s Guide Aliases For the most part end users will not be using these functions / features and / or should use the default settings. For more information please see the Advanced User Manuals or consult with your Systems Integrator Alias : This field is to create or delete aliases that are registered with the gatekeeper.
TVP-221H User’s Guide 4.4 Dial Plan Settings Dial Plan Setup Using the function scroll bar on the right, you are able to Add, Delete, Find or List data to/from one of 3 tables (While it may appear that there are 5 tables, Remote Destination IP, Remote_Host_ Nam e, and Local_Destination Channel are all part of the Destination Table).
TVP-221H User’s Guide From this window, we can Add / Dele te / Find or List desired telephone numbers and map them to a hunt group. Parameter Description Telephone Number Telephone number to match. This is only part of the total dialed string. Hunt Group ID For each hunt group ID, you need to assign it a unique identifier between 0 and 99.
TVP-221H User’s Guide 34 From this window, we can Add / Delete / Find or List the desired hunt group ID and map it to a destination ID. Destination ID Table 1. From Navigat ion Bar, Select Dial Plan Settings / Di al Plan Table Setup. 2. The default values are Add and Telephone .
TVP-221H User’s Guide 35 Each telephony port of the TVP-221H mu st be assigned a unique destination ID. Fill out the worksheet for local destinations by designating each port a unique destination ID, 4.
TVP-221H User’s Guide 36 and a remote phone rings without digits be ing dialed. This is a useful tool for customer requirements such as: • The provision of an Off-Premises eXtension (OPX) from a private branch exchange (PBX).
TVP-221H User’s Guide 37 4.44 Clear Dial Plan Clear Dial Plan - Will clear the Dial Plan from DRAM / Working mem ory. DRAM – Everytime you make an entry into the Address Table, Hunt Group Table or Destination ID table, you have to Click on Complete.
TVP-221H User’s Guide Total Time The total amount of time you have to enter a telephone number (Default 30000ms) First Digit Wait Time The amount of time you have to enter your first digit (Default .
TVP-221H User’s Guide Firmware Web Browser. Administration Password Setup / Login The Administ ration Password Page allows you to change your password on the TVP-221H. To change your password, navigate to Password from the main Adm inistration Me nu.
TVP-221H User’s Guide Enter the default "User Nam e" and the "Password" you set on the Administrat ion Password Setup screen above. Remote Administration Remote Administration allows you to connect to this interface vi a the Internet, using your Web browser or Telnet.
TVP-221H User’s Guide from the Internet. IP Address To manage this device via the Inte rnet, you need to know the IP Address of this device, as seen fro m the Internet. This IP Address is allocated by your ISP. However, if y ou are using a Dynamic IP Address, this value can change each time you connect to your ISP.
TVP-221H User’s Guide Update Click this button to start t he Firmware upgrade. Note than any users accessing the Internet via the TVP- 221H will lose their connection. When the upgrade is finished, the TVP-221H will restart, and this management connection will be unavailab le during the restart.
TVP-221H User’s Guide 43 Interface Speed 1. Select AUTO, 10 MB Full-Duplex or 100 MB Full-Duplex 2. Click on OK 3. Reboot 4.8 Channel S t atus View all settings made to each Channel (port). Simply Select the Channel (0- 3) and Click on View 4.9 Help Here you will find helpful definitions to common parame ters in the TVP-221H User Interface.
TVP-221H User’s Guide 44 Chapter 5 Making Calls with TVP-221H This chapters shows how to make phone call s from telephony devices connected to the TVP-221H directly through or i ndirectly. 5.1 Configuration Examples Default Dial Plan Before any configuration set up, your TVP should have the following basic information.
TVP-221H User’s Guide Hint You may also check t he LED indicators on the TVP-221H. When it rings, the related LED should fl ash. After you pick up the handset, it shoul d remain on and off when t he phone is on hook. Now let’ s test your TVP-221H that is equipped with 2 FXO interfaces.
TVP-221H User’s Guide Operation: 1. Pick up this analogue telephone set. You should be able to hear the dial tone provided by the TVP-221H. 2. The corresponding green LED will light up when the telephone set is picked up. For Example: If the telephone set is connected to the second port of FXS.
TVP-221H User’s Guide Draw an application diagram to illustrate / clarify application including: 1. Local gateway: IP setup 2. Local gateway: local telephone number setup 3.
TVP-221H User’s Guide 48 in Taiwan (Local Area Code have 2 digits) and GW B is in the US (Local Area Codes have 3 digits). Gatew ay A, 4 ports, is configured as follows: 1. Gateway A IP: 192.168.1.20, mask IP: 255. 255.255.0, gateway IP 0.0.0.0 (virtual IP) 2.
TVP-221H User’s Guide The following screen shots show an example for entering a dial plan for a single number. This example should give you the nec essary insight as to how to enter the rest of the Dial Plan. If you still have di fficulty understanding the dial plan and entering data, please reference the User Manual for more examples.
TVP-221H User’s Guide 50 1. Continue entering the Gateway A Dial Plan as laid out in the tables below (Telephone Table, Hunt Group Table and Destination Table) following the above procedures. 2. After you have entered the Dial Plan, make sure you Store Dial Plan to flash memory.
TVP-221H User’s Guide 51 dials “800”. applicable 801 5 3 3 0 None Dialing “801” calls PBX on FXO Port 0, which then dials “801”. This is an example only. Please substitute your ext# on PBX if applicable 9 6 1 1 0 None Dialing “9” from local phone on FXS Port connects you FXO Port 0 PBX, where “9” is dialed for outside line.
TVP-221H User’s Guide 52 3 Local Port = 3 4 Local Port = 0 22 Remote Dest = 192.168.0.55/1720 TCP L The above destination table has both local destinations and remote destinations. When the gateways are ta ken out of this initial testing environment, and implemented in the field, the internet access settings will have to be updated.
TVP-221H User’s Guide 53 11 2 1 11 Gateway B - Destination table Dest ID Mode Destination 2 Local Port = 2 3 Local Port = 3 4 Local Port = 0 11 H.323 Dest = 192.168.0.20/1720 TCP L The above destination table has both local destinations and remote destinations.
TVP-221H User’s Guide 54 The above process is the same for Gateway B phone 203 and 204 calls to Gateway A phone 201, 800 and 801 . Case 2: Gateway Phone to PSTN Phone Gatew ay B phone 203 calls to PSTN phone A number 7777-1234 Caller Operation at GW B Equipment Operation Receiver Operation at GW A Pick up phone 203 (204) on GW B 1.
TVP-221H User’s Guide 55 Dial 22203 (22204) 1. Du Du tone is heard 2. VoIP call processing Ring back tone is heard 1. GW A Line 1 LED “ON” Phone 203 is ringing 1.
TVP-221H User’s Guide 56 The first time you connect to the TVP-221H for configuration, you will need to connect to it under the same LAN segment to set the DHCP or PPPoE client. To configure the TVP-221H, insert one end of an Ethernet cable into the RJ45 WAN port on the rear panel of the TVP-221H and the ot her end directly to your PC Terminal.
TVP-221H User’s Guide TVP-221H configuration (ADSL PPPoE connection) on site A Web Configuration Telnet / Console Local (from PC in same Segment) Open your browser 1. Enter 192.168.0.1 2. You will be prompted for Username and Password. Default Username and Password are “admin” and “123” respectively.
TVP-221H User’s Guide Web Configuration of Internet Access Internet Access / PPPoE 1. Select “Yes” to enable PPPoE function 2. Enter username and password provided by your ISP 3. Click on “Save” Internet Access / Dynamic DNS 4. Select Enable 5.
TVP-221H User’s Guide Dial Plan Settings / Dial plan Table Setup 11. Select “Add” and “HuntGroup” 12. Enter following fields a. Hunt Group ID: 22 b. Destination ID: 22 13. Click on “OK” Dial Plan Settings / Dial plan Table Setup 14. Select “Add” and “Remote_Host_Name” 15.
TVP-221H User’s Guide Web Configuration of Internet Access Internet Access / DHCP Client 24. Select “Yes” 25. Click on “Save” Internet Access / Dynamic DNS 26. Select Enable 27. Enter Server Name, Host Name, User Name, Password (eg. dyndns.org tvp2 username2 password2) 28.
TVP-221H User’s Guide Setup 33. Select “Add” and “HuntGroup” 34. Enter following fields a. Hunt Group ID: 11 b. Destination ID: 11 35. Click on “OK” Dial Plan Settings / Dialplan Table Setup 36. Select “Add” and “Remote_Host_Name” (eg.
TVP-221H User’s Guide 62 TVP-221H can be configured with a Router. In this example, Trendwares TEW- 431BRP is used. Internet Access In addition to fixed IP, the TEW-431BRP can be configured to use PPPoE or DHCP clients.
TVP-221H User’s Guide 3. Enter username / password and domain name (hostname) as registered with www.dyndns.org 4. Click on Save , and wait a few seconds to verify if DDNS service has taken effect. DDNS Status should appear. You can also verify by checking the Status page.
TVP-221H User’s Guide 6. Select the device and check enable 7. Click on Save Note: Defining your own Virtual Servers If the type of Server you wish to use is not listed on the Virtual Servers screen, you can use the Firewall Rules to allow particular incoming traffic and forward it to a specified PC (Server).
TVP-221H User’s Guide 65 Properties Enable Use this to Enable or Disable support for DMZ, as required. If Enabled, any incoming connections will be forwarded to the selected PC.
TVP-221H User’s Guide 66 After these dial plans are added, users on Site A are able to dial “22 + extension number” to connect to users on site B for free VoIP telephony. Users on Site B are able to call phones on Site A for free VoIP telephony by dialing “11 + extension number”.
TVP-221H User’s Guide TVP-221H configuration (ADSL PPPoE connection) on site A Web Configuration Telnet / Console Local (from PC in same Segment) Open your browser 1. Enter 192.168.0.1 2. You will be prompted for Username and Password. Default Username and Password are “admin” and “123” respectively.
TVP-221H User’s Guide Web Configuration of Dial Plan Dial Plan Settings / Dialplan Table Setup 4. Select “Add” and “Telephone 5. Enter following fields g. Telephone Number: 22 h. Hunt Group ID: 22 i. Min. Digits : 2 j. Max. Digits : 5 k. Strip Length: 2 l.
TVP-221H User’s Guide Open your browser Connect RS-232 to TVP-224HR and PC Enter 192.168.01 1. You will be prompted for Username and Password. Default Username and Password are “admin” and “123” respectively.
TVP-221H User’s Guide Web Configuration of Dial Plan Dial Plan Settings / Dial plan Table Setup atpm req 3. Select “Add” and “Telephone atpm aadd 11 2 5 11 2 4. Enter following fields r. Telephone Number:11 s. Hunt Group ID: 11 t. Min. Digits : 2 u.
TVP-221H User’s Guide Case 6: PLAR (Hotline) FXO to FXS example Site A Site B This could be a call placed from any outside PSTN numbe r Case Scenario: Outside PSTN caller near Site A wants calls automatically forwarded to extension 203 on Site B.
TVP-221H User’s Guide 72 Site A TVP Gateway configuration - FXO to FXS PLAR Telnet / Console Web Configuration Login in to Site A TVP Gateway From Console Logon to the Web Configurati on by opening your browser Enter Username “admin” Enter Password “123” 1.
TVP-221H User’s Guide Case 7: PLAR (Hotline) FXS to FXO example FXO 201 Site A Site B Caller on Site B could dial any Site A local PSTN numbe r Case Scenario: Caller on Site B FXS 203 wants to be able to pick up phone and imme diately have dial tone to Site A local PSTN.
TVP-221H User’s Guide 74 Site B TVP Gateway Configuration - FXS to FXO PLAR Telnet / Console Web Configuration Login to Site A TVP Gateway From Console 1. Logon to the Web Configurati on by opening your browser Enter Username “admin” Enter Password “123” 2.
TVP-221H User’s Guide 75 Case Scenario: Site A Site B Caller on Site A PBX could pick up any PBX extension FXO (201) FXO (201) Site A PBX Extension Caller 316 wants to be able to pick up phone, dial a number and immediately have dial tone on Site B PBX, and then be able to call any Site B PBX extension.
TVP-221H User’s Guide Telnet / Console Web Configuration Login to Site A TVP Gateway From Console 1. Logon to the Web Configurati on by opening your browser Enter Username “admin” Enter Password “123” Enter 192.168.0.20 2. You will be prompted for Username and Password.
TVP-221H User’s Guide 6 Chapter 6 Connection Considerations This section discusses the special connection consideration for various environment s and situations where you can use the VoIP Gate way. 6.1 Port Configuration V oIP Gateway supports FXS and FXO ports.
TVP-221H User’s Guide 78 Application 1: Special FXS Connections The following diagram illustrates two dif ferent types of connections. The SITE A FXS Connection shows the normal connec tion between a gateway and telephone set (POTS) or F AX machine.
TVP-221H User’s Guide 1 7 Chapter 7 Troubleshooting Tips This section provides soluti ons for problems you may possibly encounter while instal ling and connecting your VoIP Gateway. Power (PWR) LED is not illuminate 1. Check the power adapter connection.
TVP-221H User’s Guide 80 2. Check the IP network (Ethernet cable, Ethernet port and GW IP setting) is connected correctly 3. Check the destination TVP-221H and phone is available Final S teps If the procedures in this section have not solved the problem, reset the gateway by turning the power on and off.
TVP-221H User’s Guide Appendix A - T echnical S pecifications TVP-221H Technical Specifications Telephony Interface Physical interface Desktop with 4 Analog Ports • Loop start 2 x FXO (RJ-11) • Loop start 2 x FXS (RJ-11) Programmable line interfaces Complex line impedance H.
TVP-221H User’s Guide 82 Telephony Line Module Specifications FXO Ports Signaling Loop start/DTMF Number of channels 2 Interface connectors 2 RJ-11 2-pin m odular jacks Line impedance 600 900 Com plex line impedance Insertion loss 2 dB nominal Frequency response 300 Hz ~ 3400 Hz +/- 2 dB w.
TVP-221H User’s Guide 83 Console Port The console port uses a DB-9 RS-232 connector. The supplied straight through RS-232 cable connects the console port of the TVP-221H to a console PC or terminal. Pin assignment for the port is described in the following table.
TVP-221H User’s Guide FXO Port Pin Assignments The FXO Telephony Interface Module has 2 RJ11C/W modular jacks. The following diagram and table show the assignments of the pin for the RJ11 port.
TVP-221H User’s Guide 85 The console port uses a DB-9 RS-232 connec tor. The supplied straight through RS- 232 cable connects the console port of the T VP-221H to a console PC or terminal.
TVP-221H User’s Guide 86 ping (xxx.xxx.xxx.xxx): 56 data bytes xxx.xxx.xxx.xxx is alive If the ping times out, you do not have Internet Access or the Public IP Address you used is incorrect.
TVP-221H User’s Guide 87 Appendix C – Connecting Thr ough T elnet To use Telnet, Internet Access must have been previously setup so that the gateway is visible on the internet (See User Guide fo r More Information).
TVP-221H User’s Guide 88 Appendix D – CLI Commands Normal Mode Commands Command Description atpm aadd Add an entry to the address table atpm adel Delete an entry from the address table atpm afind .
TVP-221H User’s Guide 89 net set gateway Set default gateway’s IP address net set http Turn on/off HTTP server net set ip Set IP address net set ip_preced Set IP precedence bits net set mask Set I.
TVP-221H User’s Guide 90 Appendix E - Factory Default Settings The following table lists the settings of cer tain param eters before the TVP-221H is shipped. Parameter Default Setting Network PPPoE disabled DYN DNS disabled DHCP client disabled Configured IP address 192.
TVP-221H User’s Guide 91 h323 out_fast_start Off h323 in_fast_start Off h323 h245_tunneling Off h323 cisco_t38 On h323 callSignalPort 1720 h323 call_name None h323 local_alert Off h323 default_dtmf H323 V2 Signal h323 gk_mode Off h323 h245_timeout 30000 h323 term_id None h323 refresh 120 Voice codec Preferred voice codec G.
TVP-221H User’s Guide 92 Appendix F - Worksheet s IP Parameters Consult your network manager to obtain a static IP address for the TVP-221H, and the information about the IP subnet m ask and the default gateway for your network. Fill out the following work sheet before configuring the TVP-221H.
TVP-221H User’s Guide 93 Remote Destinations Each remote TVP-221H to be reached mu st be assigned a unique destination ID. Obtain the IP addresses of the TVP-221H at remote sites and fill out the wo.
TVP-221H User’s Guide 94 ATPM Hunt Group Table Several destinations may be groupe d together to form a hunt group. When an incoming phone num ber matches the phone number of the hunt group, the TVP- 221H attempts to term inate the call at each of the destinations in the hunt group one at a tim e until a call is successfully completed.
TVP-221H User’s Guide 95 ATPM Address Table Each phone number to be recognized by th e TVP-221H must have its first digits match an entry in the address table.
TVP-221H User’s Guide 96 A Address Table............................. 17 Administration............................ 38 Aliases ........................................ 31 Append Prefix ............................ 33 ATPM............................
TVP-221H User’s Guide 97 K KTS ........................................ 4, 10 L LAN Port .................................... 82 LED ........................................ 4, 11 Line Settings............................... 37 M Max Registration Retries .
TVP-221H User’s Guide Limited Warranty TRENDware warrants its products against defect s in material and workmanship, under norm al use and service, for the following lengt hs of time from the date of purchase.
TVP-221H User’s Guide 99 INCIDENTAL, CONSEQUENTIAL, INDIRECT , SPECIAL, OR PUNITIVE DAMAGES OF ANY KIND, OR FOR LOSS OF REVENUE OR PROFITS, LOSS OF BUSINESS, LOSS OF INFORMATION OR DATE, OR OTHER FI.
TVP-221H User’s Guide 100.
デバイスTRENDnet TVP- 221Hの購入後に（又は購入する前であっても）重要なポイントは、説明書をよく読むことです。その単純な理由はいくつかあります：
TRENDnet TVP- 221Hをまだ購入していないなら、この製品の基本情報を理解する良い機会です。まずは上にある説明書の最初のページをご覧ください。そこにはTRENDnet TVP- 221Hの技術情報の概要が記載されているはずです。デバイスがあなたのニーズを満たすかどうかは、ここで確認しましょう。TRENDnet TVP- 221Hの取扱説明書の次のページをよく読むことにより、製品の全機能やその取り扱いに関する情報を知ることができます。TRENDnet TVP- 221Hで得られた情報は、きっとあなたの購入の決断を手助けしてくれることでしょう。
TRENDnet TVP- 221Hを既にお持ちだが、まだ読んでいない場合は、上記の理由によりそれを行うべきです。そうすることにより機能を適切に使用しているか、又はTRENDnet TVP- 221Hの不適切な取り扱いによりその寿命を短くする危険を犯していないかどうかを知ることができます。
ですが、ユーザガイドが果たす重要な役割の一つは、TRENDnet TVP- 221Hに関する問題の解決を支援することです。そこにはほとんどの場合、トラブルシューティング、すなわちTRENDnet TVP- 221Hデバイスで最もよく起こりうる故障・不良とそれらの対処法についてのアドバイスを見つけることができるはずです。たとえ問題を解決できなかった場合でも、説明書にはカスタマー・サービスセンター又は最寄りのサービスセンターへの問い合わせ先等、次の対処法についての指示があるはずです。
