FCCID.CO- FCC ID Database
HomeCompaniesEquipment ClassesSearch

© 2026 FCC ID Database. All rights reserved.

AboutContactData sourced from FCC public records
  1. Home/
  2. Snap One, LLC/
  3. R33C4DSC

R33C4DSCEXTERIOR DOOR STATION

Snap One, LLC
EXTERIOR DOOR STATION - FCC ID R33C4DSC - Snap One, LLC
Click to zoom

Application Details

Equipment Class
DTS - Digital Transmission System
Date of Grant
Aug 28, 2012
Application Purpose
Original Equipment
Date of Application
Aug 28, 2012
Equipment Note
EXTERIOR DOOR STATION
Frequency Range
2412.00000000 - 2462.00000000
Company
Snap One, LLC
Country
United States

Documents & Files

Select a file to view

Users Manual

↗

Cover Letter(s)

↗
↗
↗
↗

External Photos

↗

ID Label/Location Info

↗
↗

Internal Photos

↗

RF Exposure Info

↗

Test Report

↗

Test Setup Photos

↗

Document Text

Text extracted from the exhibit documents filed with the FCC. Open a document above to read the original.

Users Manual

™ Requirements • Tools to install the back box, such as a tape measure, pencil, hammer or screwdriver • Nails or screws (4 to 6) • Antenna Kits (optional, sold separately) - Antenna, 12” (C4-AK-26cm) - External Antenna, 10’, EWA 2450M (C4-AK-3M) Specifications Dimensions (H x W x D) 6.1” x 4.1” x 3” (156 mm x 104 mm x 76 mm) Weight1.10 lbs. NetworkEthernet or WiFi (802.11 b/g/n) Grounding Requirements The following table indicates which power options require an earth ground. Power TypeEarth Ground? ACYes, required for safety. Power Over Ethernet (PoE)No. Do not connect. DCRecommended; not required. Network and Power Considerations This device uses an Ethernet or WiFi network connection and can be powered using PoE, AC, or DC. NOTE: It is recommended to use Ethernet rather than WiFi for the best network connectivity. See the Door Station - Exterior Setup Guide for wiring installation details. Mounting Tips Follow these tips for best results. 1 Install the Door Station in a place where it will be protected from water (e.g., rain, sprinklers, etc.). 2 Do not expose the Door Station to direct sunlight. For installations in direct sunlight, the Satin Nickel model (C4-DCS-EN-SN) will yield the least amount of color fading. 3 Find an appropriate exterior location for the Door Station. Also see the Door Station - Exterior Setup Guide for back box placement. a Mount the Door Station where the video Supported Model • C4-DSBB-E-M Door Station Metal Back Box Figure 1. Door Station Back Box General Description Control4® provides a back box to accommodate the installation of a Control4 Door Station - Exterior (C4- DSC-EN-xx). Box Contents Unpack the Door Station Back Box and ensure the following items are included in the box. Contact your Control4 Dealer immediately if you find any missing or damaged components. • Control4 Door Station Back Box (model C4-DSBB-E-M) Door Station Back Box Installation Guide 1 ™ camera is aimed at an average person’s height so the viewer can see the person calling in. b Mount the Door Station so that the caller can comfortably speak into the microphone or about 18” to 2’ away (45 cm x 60 cm). 4 It is not recommended to use wireless (WiFi) for an outside installation. If you use WiFi, follow these tips: • Place the Door Station in a location where the wireless signal (WAP broadcast) is strong. • Place the access point in a clear line of sight or less than 100 feet, if possible. • Place the access point where it will have the least number of walls to pass through. • Place the access point on the second level by a window. • Use Composer Pro’s, System Manager to test the wireless signal after you’ve installed the Door Station. • Verify that the signal works. See the Door Station - Exterior Setup Guide (when the Door Station is released) for WiFi installation instructions. Installation NOTES: (1) Place the back box between studs. Do not attempt to install a back box over a wall stud. (2) To conform to NEMA safety standards, install a strain-relief cord (sold separately) in the punchout on the back box before inserting the wires. See “Regulatory Information” or the NEMA website at: http:// www.nema.org/stds/ for details. Door Station Back Box Installation Guide IMPORTANT! Make sure the back box protrudes far enough out (0.118” or 3 mm) from the exterior wall surface (brick, rock, stucco, wood, concrete, etc.) to allow the plate and gasket to seal the Door Station (see Figure 2). Figure 2. Back Box Side View in Wall with Door Station Faceplate 1 Feed the AC, DC, or PoE wires through a tab in the back of the back box. See the Door Station - Exterior Setup Guide to determine your installation option. 2 After placing the back box inside the wall, secure the box with screws or nails. 3 Attach the ground wires to the back box as needed (see “Grounding Requirements” on page 1) and Door Station plate in the location indicated by the ground symbol (see Figures 3 and 4). There are two (2) ground screws in the back box: one (1) for Earth ground and one (1) for grounding the Door Station faceplate to the back box. 2 Figure 4. Gound Wires from Door Station to Back Box Warnings IMPORTANT! Improper use or installation can cause LOSS/DAMAGE OF PROPERTY. Important! L’utilisation ou l’installation inexacte peut causer LOSS/DAMAGE DE PROPRIÉTÉ. WARNING! Before you install the Door Station Back Box using AC, switch off the circuit breaker or remove the fuse from the fuse box. AVERTISSEMENT! Pour l’endroit où vous installez station de porte avec AC, coupez le disjoncteur ou enlevez le fusible de la boîte de fusible. Regulatory/Safety Information To review regulatory information for your particular Control4 products, see the information located on the Control4 website at: http://www.control4.com/ regulatory/ 4 If using WiFi, the WiFi antenna must be installed in the back box and extend outside the box. NOTE: Do not allow any contact of the antenna element to any metal surface on the back box; otherwise, antenna performance will diminish. Figure 3. Ground Wire to Door Station WARNING! For AC installation, failure to ground the metal back box and Door Station faceplate properly can result in a potentially hazardous condition. AVERTISSEMENT! Pour installation d’AC, défaut de brancher la mise à la terre de la boîte arrière en métal et la façade avant correctement peut entraîner une situation dangereuse. 3 Ground Wire Ground Wire Back Box Door Station Faceplate ©2012 Control4. All rights reserved. Control4, the Control4 logo, the Control4 iQ logo and the Control4 certified logo are registered trademarks or trademarks of Control4 Corporation in the United States and/or other countries. All other names and brands may be claimed as the property of their respective owners. control4.com | ™ 4 Warranty Limited 2-year Warranty. Go to http://www.control4. com/warranty for details. About This Document Part number: 200-00244, Rev. E 6/05/2012 ™ Specifications Dimensions (H x W x D) 7.19” (182 mm) x 5.13” (130 mm) …

Text truncated - open the document above for the full version.

Cover Letter(s)

11734 South Election Road, Ste. 200 | Salt Lake City, Utah 84020 | www.control4.com | 801.523.3100 phone | 801.523.3199 fax Timco Engineering 849 N.W. State Road 45 PO Box 370 Newberry, FL 32669 Attn: Director of Certification Authority to Act as Agent FCC On our behalf, I authorize Tom Jackson, General Manager, or Merry Jackson, Officer Manager, of Nemko-CCL, Inc. Nemko-CCL, Inc. at 1940 W. Alexander Street, Salt Lake City, UT 84119, to act as our agent in the preparation of this application for equipment certification. I certify that submitted documents properly describe the device or system for which equipment certification is sought. I also certify that each unit manufactured, imported or marketed, as defined in Federal Communications Commission regulations will have affixed to it a label identical to that submitted for approval with this application. In signing this letter, Applicant certifies that neither the applicant nor any party to the application is not subject to a denial of Federal benefits, that include FCC benefits, pursuant to Section 5301 of the Anti-Drug Abuse Act of 1988, 21 U.S.C. § 862 because of a conviction for possession or distribution of a controlled substance. See 47 CFR 1.2002(b) for the definition of a "party" for these purposes. For instances where our authorized agent signs the application for certification on our behalf, I acknowledge that all responsibility for complying with the terms and conditions for certification, as specified by Timco Engineering still resides with Control4 at 11734 South Election Road, Suite 200, Draper UT 84020-6432, USA. Dated this 15 Day of June 20 12 Agency agreement expiration date: December 31, 2012 By: Roger Midgley Signature Printed Title: Sr. Regulatory Compliance Engineer On behalf of : Control4 Telephone: (801) 523-3187

Cover Letter(s)

11734 South Election Road, Ste. 200 | Salt Lake City, Utah 84020 | www.control4.com | 801.523.3100 phone | 801.523.3199 fax July 23, 2012 CONFIDENTIALITY REQUEST LETTER Federal Communications Commission Authorization and Evaluation Division Confidentiality Request regarding application for certification of FCC ID: R33C4DSC Pursuant to Sections 0.457 and 0.459 of the Commission’s Rules, we hereby request confidential treatment of information accompanying this application as outlined below: Exhibit Type File Name Schematics C4-DSC-EN Schem.pdf Block Diagram C4-DSC-EN BlkDia.pdf Operational Description C4-DSC-EN OpDes.pdf The above materials contain trade secrets and proprietary information not customarily released to the public. The public disclosure of these materials may be harmful to the applicant and provide unjustified benefits to its competitors. The applicant understands that pursuant to Section 0.457 of the Rules, disclosure of this application and all accompanying documentation will not be made before the date of the Grant for this application. Sincerely, Roger Midgley Sr. Regulatory Compliance Engineer

Cover Letter(s)

11734 South Election Road, Ste. 200 | Salt Lake City, Utah 84020 | www.control4.com | 801.523.3100 phone | 801.523.3199 fax ATT-001 Issue 1 March 2012 MANUFACTURER’S STATEMENT/ATTESTATION Applicant: Control4 Address: 11734 South Election Road, Suite 200 Draper, UT 84020 USA Contact Name: Roger Midgley Title: Sr. Regulatory Compliance Engineer Brand Name: Control4 Model Number: C4-DSC-EN FCC ID/IC ID: R33C4DSC/7848A-C4DSC Brand Name: Cisco Model Number: SCH-VDS-E Nemko-CCL Test Reports: 205425-2, 205425-3, 205425-4, 205425-5 and 205425-6 The manufacturer or responsible party for the equipment tested hereby affirms: a) That he/she has reviewed and concurs that the tests shown in this report are reflective of the operational characteristics of the device for which certification is sought; b) That the device in this test report will be representative of production units; c) That the product will have all of the documented modifications incorporated into the product when manufactured and placed on the market; d) That all changes in hardware and software/firmware to the subject device will be reviewed. e) That any changes impacting the attributes, functionality or operational characteristics documented in this report will be communicated to the body responsible for approving or certifying the subject equipment. Roger Midgley July 23, 2012 Authorized Representative (please print) Signature Date

External Photos

Front View of the EUT Back View of the EUT Inside Back Box

ID Label/Location Info

11734 South Election Road, Ste. 200 | Salt Lake City, Utah 84020 | www.control4.com | 801.523.3100 phone | 801.523.3199 fax C4-DSC-EN & SCH-VDS-E Label Label Example (Control4): Label Example (Cisco):

ID Label/Location Info

11734 South Election Road, Ste. 200 | Salt Lake City, Utah 84020 | www.control4.com | 801.523.3100 phone | 801.523.3199 fax C4-DSC-EN & SCH-VDS-E Label Placement Label is placed on the bottom side of the C4-DSC-EN as shown in the drawing below:

Internal Photos

Back View of the EUT With Back Box Removed View of the Component Side of the Power PCB View of the Trace Side of the Power PCB View of the EUT with Back Box and Power PCB Removed View of the Component Side of the Main/RF PCB View of the Trace Side of the Main/RF PCB View of the Switch Side of the LED/Switch PCB View of the Trace Side of the LED/Switch PCB View of the Imager Side of the Camera PCB View of the Trace Side of the Camera PCB View of the Sleeve Antenna View of the Patch Antenna

RF Exposure Info

Page 1 of 4 11734 South Election Road, Ste. 200 | Salt Lake City, Utah 84020 | www.control4.com | 801.523.3100 phone | 801.523.3199 fax MPE Calculations Control4 Model: C4-DSC-EN Cisco Model: SCH-VDS-E FCC ID: R33C4DSC IC ID: 7848A-C4DSC Page 2 of 4 11734 South Election Road, Ste. 200 | Salt Lake City, Utah 84020 | www.control4.com | 801.523.3100 phone | 801.523.3199 fax 1.0 SCOPE_________________________________________________________3 2.0 REVISION LEVEL_______________________________________________3 3.0 REFERENCE DOCUMENTS______________________________________3 4.0 CALCULATIONS________________________________________________4 5.0 CONCLUSION___________________________________________________4 1.0 SCOPE: This Report Demonstrates Evaluation and Compliance to the following standards: 1. Code of Federal Regulations Title 47, Volume 1, Section 1.1310. 2. Radio Frequency Exposure Compliance of Radiocommunication Apparatus (All Frequency Bands) - RSS-102 Issue 3 2.0 REVISION LEVEL: DATE COMMENTS REVISION 10/10/08 Created. 1.0 08/16/10 Added RSS-102 references 2.0 3.0 REFERANCE DOCUMENTS: (A) Limits for Maximum Permissible Exposure (MPE). Code of Federal Regulations Title 47, Volume 1, Section 1.1310. (B) Evaluating Compliance with FCC Guidelines for Human Exposure to Radiofrequency Electromagnetic Fields. OET Bulletin 67 Edition 97-01. (C) Radio Frequency Exposure Compliance of Radiocommunication Apparatus (All Frequency Bands) - RSS-102 Issue 3 Page 3 of 4 11734 South Election Road, Ste. 200 | Salt Lake City, Utah 84020 | www.control4.com | 801.523.3100 phone | 801.523.3199 fax 4.0 CALCULATIONS: The C4-DSC-EN contains an 802.11 b/g/n Transceiver. The worst case emissions were with the C4-DSC-EN transmitting on 802.11 n mode. Below is the MPE calculation for this Transceiver. 802.11 n Transceiver The following worst case emissions was calculated by using Method 1 below Method 1: Based on a PPt (Peak Power Total) measurement of the total power into the antenna and the worst case antenna gain. Effective/Equivalent Isotropic Radiated Power [EIRP] dBm = Total power into the antenna [dBm] + antenna gain [dBi] To convert the values from dBm to mW mW = 10 dBm/10 Total power into the antenna (dBm) = 23.11 Antenna gain (dBi) = 1.41 EIRP (dBM) = 24.52 EIRP (mW) = 283.14 worst case while in the Wi-Fi “n” mode Method 2: Based on the radiated field strength measurement at 3 meters [at a calibrated OATS site, maximizing the antenna polarity and height] After obtaining the EIRP, the Power density is calculated and compared against the FCC and IC limits. S FCC = Power density in mW/cm² for FCC S FCC = EIRP/4π·R² EIRP = Equivalent isotropically radiated power 283.14 mW R = Distance to the center of radiation of the antenna 20 cm S FCC = 0.056 mW/cm² S FCC Limit = 1.0 mW/cm² S IC = Power density in W/m² for IC S IC = EIRP/4π·R² EIRP = Equivalent isotropically radiated power in watts 0.28314 W R = Distance to the center of radiation of the antenna 0.2 m S IC = 0.563 W/m² S IC Limit = 10 W/m² for IC Page 4 of 4 11734 South Election Road, Ste. 200 | Salt Lake City, Utah 84020 | www.control4.com | 801.523.3100 phone | 801.523.3199 fax 5.0 CONCLUSION: 1. Based upon the limits for Maximum Permissible Exposure (MPE) given in Table 1 of reference document (A) as 1mW/cm², this device falls under the required limits. 2. Based upon the limits given in section 4.2 of the reference document (C) as 10W/m², this device falls under the required limits.

Test Report

Nemko-CCL, Inc. 1940 West Alexander Street Salt Lake City, UT 84119 801-972-6146 Test Report Certification Test Of: C4-DSC-EN and SCH-VDS-E FCC ID: R33C4DSC Test Specifications: FCC PART 15, Subpart C Test Report Serial No: 205425-3.1 Applicant: Control4 11734 S. Election Road, Suite 200 Draper, UT 84020 Dates of Test: April 23, 24 & 26, 2012 June 6, 7 & 11, 2012 Report Issue Date: July 18, 2012 Accredited Testing Laboratory By: NVLAP Lab Code 100272-0 Nemko-CCL, Inc. TEST REPORT: 205425-3.1 REPORT ISSUE DATE: 7/12/2012 Page 2 of 123 CERTIFICATION OF ENGINEERING REPORT This report has been prepared by Nemko-CCL, Inc. to document compliance of the device described below with the requirements of Federal Communications Commission (FCC) Part 15, Subpart C. This report may be reproduced in full, partial reproduction may only be made with the written consent of the laboratory. The results in this report apply only to the sample tested. - Applicant: Control4 - Manufacturer: Control4 - Brand Name: Control4 - Model Number: C4-DSC-EN - Brand Name: CISCO - Model Number: SCH-VDS-E - FCC ID Number: R33C4DSC On this 12 th day of July 2012, I, individually and for Nemko-CCL, Inc., certify that the statements made in this engineering report are true, complete, and correct to the best of my knowledge, and are made in good faith. Although NVLAP has recognized that the Nemko-CCL, Inc. EMC testing facilities are in good standing, this report must not be used to claim product certification, approval, or endorsement by NVLAP, NIST, or any agency of the federal government. Nemko-CCL, Inc. Tested by: Norman P. Hansen EMC Technician Reviewed by: Thomas C. Jackson General Manager Nemko-CCL, Inc. TEST REPORT: 205425-3.1 REPORT ISSUE DATE: 7/12/2012 Page 3 of 123 TABLE OF CONTENTS PAGE SECTION 1.0 CLIENT INFORMATION .................................................................................4 SECTION 2.0 EQUIPMENT UNDER TEST (EUT) ..................................................................5 SECTION 3.0 TEST SPECIFICATION, METHODS & PROCEDURES .............................9 SECTION 4.0 OPERATION OF EUT DURING TESTING ..................................................15 SECTION 5.0 SUMMARY OF TEST RESULTS ...................................................................16 SECTION 6.0 802.11b/g/n TRANSCEIVER – MEASUREMENTS AND RESULTS ..........17 APPENDIX 1 TEST PROCEDURES AND TEST EQUIPMENT ..........................................91 APPENDIX 2 PHOTOGRAPHS ................................................................................................97 Nemko-CCL, Inc. TEST REPORT: 205425-3.1 REPORT ISSUE DATE: 7/12/2012 Page 4 of 123 SECTION 1.0 CLIENT INFORMATION 1.1 Applicant: Company Name: Control4 11734 S. Election Road, Suite 200 Draper, UT 84020 Contact Name: Roger Midgley Title: Sr. Regulatory Compliance Engineer 1.2 Manufacturer: Company Name: Control4 11734 S. Election Road, Suite 200 Draper, UT 84020 Contact Name: Roger Midgley Title: Sr. Regulatory Compliance Engineer Nemko-CCL, Inc. TEST REPORT: 205425-3.1 REPORT ISSUE DATE: 7/12/2012 Page 5 of 123 SECTION 2.0 EQUIPMENT UNDER TEST (EUT) 2.1 Identification of EUT: Brand Name: Control4 Model Number: C4-DSC-EN Serial Number: Engineering Unit Brand Name: Cisco Model Number: SCH-VDS-E Dimensions: 18.2 cm x 13.0 cm x 5.8 cm 2.2 Description of EUT: The C4-DSC-EN is an exterior door station that provides video and audio to home control system devices. The C4-DSC-EN has an 802.11bgn transceiver and an Ethernet port for interfacing the home control system. The C4-DSC-EN may be powered by AC, POE, or a DC source. For testing using POE, an Ault PW130 POE injector was used to power the EUT. For testing using a DC source, a Delta Electronics 0950-4466 power supply was used. A contact/relay port is provided to interface sensors or contacts of devices such as gates, doors, or doorbells. The C4-DSC-EN has a metal back box that is placed in a wall and a metal front faceplate. The faceplate color is designated by 2 letters after the model number. Available color options are: BL for satin black, OB for oil rubbed bronze, VB for Venetian bronze, or SN for satin nickel. The Cisco SCH-VDS-E is identical to the C4-DSC-EN except in branding and labeling. This report covers the circuitry of the devices subject to FCC Part 15, Subpart C. The circuitry of the device subject to FCC Subpart B was found to be compliant and is covered in Nemko-CCL, Inc. report #205425-2.1. The C4-DSC-EN 802.11b/g/n transceiver uses 11 channels in the 2400 to 2483.5 MHz frequency range. Testing was performed at the upper, middle, and lower channels using 802.11b, 802.11g, and 802.11n. The C4-DSC-EN transceiver uses either an Aristotle Enterprises RFA-02-D3-16W-200, 1.41 dBi sleeve antenna or a Cirocomm Technology 03A153040379240, -5.0 dBi patch antenna. The channels and the maximum transmitter power settings to be incorporated in production software are shown below. Nemko-CCL, Inc. TEST REPORT: 205425-3.1 REPORT ISSUE DATE: 7/12/2012 Page 6 of 123 Channel Frequency (MHz) Power Setting 802.11b 802.11g 802.11n 1 2412 +12 +15 +14 2 2417 +12 +17 +16 3 2422 +12 +17 +16 4 2427 +12 +17 +16 5 2432 +12 +17 +16 6 2437 +12 +17 +16 7 2442 +12 +17 +16 8 2447 +12 +17 +16 9 2452 +12 +17 +16 10 2457 +12 +17 +16 11 2462 +12 +13 +12 2.3 EUT and Support Equipment: The FCC ID numbers for all the EUT and support equipment used during the test are listed below: Brand Name Model Number Serial Number FCC ID Number or Compliance Description Name of Interface Ports / Interface Cables BN: Control4 MN: C4-DSC-EN ( Note 1) SN: R33C4DSC Door Station See Section 2.4 BN: Control4 MN: C4-HC250B-BL SN: Engineering Unit R33C4HC250 Controller Ethernet with power/Cat5e cable with RJ-45 connectors BN: Control4 MN: C4-TW7C0-BL SN: R33C4TW7C0 In-wall touchscreen display Ethernet with power/Cat5e cable with RJ-45 connectors Nemko-CCL, Inc. TEST REPORT: 205425-3.1 REPORT ISSUE DATE: 7/12/2012 Page 7 of 123 Brand Name Model Numbe…

Text truncated - open the document above for the full version.

Test Setup Photos

Front View Radiated Disturbance Worst Case Configuration – POE Power Back View Radiated Disturbance Worst Case Configuration – POE Power Front View Radiated Disturbance – AC Power Back View Radiated Disturbance – AC Power Front View Radiated Disturbance – DC Power Back View Radiated Disturbance – DC Power View Showing Worst-Case Patch Antenna Placement Front View Conducted Disturbance Worst Case Configuration – POE Power Back View Conducted Disturbance Worst Case Configuration – POE Power Front View Conducted Disturbance – AC Power Back View Conducted Disturbance – AC Power Front View Conducted Disturbance – DC Power Back View Conducted Disturbance – DC Power

Contact Information

Applicant

Roger J Midgley(Principle Compliance Engineer)
[email protected]8015233187Fax: 801 523 3199

Test Firm

VPI TechnologyJason Stewart
[email protected]801-495-2310

Technical Specifications

#Rule PartsFrequency RangePower Output
115C2.41 GHz - 2.46 GHz283.14 mW
Confidentiality
Long Term
Grant Notes
This device must be professionally installed and include the circuit modifications listed in the Test Report. Power listed is conducted. The antenna installation and operating configurations of this transmitter, including any applicable antenna gain and cable loss must satisfy MPE categorical Exclusion Requirements of �2.1091. The antenna(s) used for this transmitter must be installed to provide a separation distance of at least 20 cm from all persons and must not be co-located or operated in conjunction with any other antenna or transmitter. Users and installers must be provided with antenna installation instructions and transmitter operating conditions for satisfying RF exposure compliance.

Other Applications from Snap One, LLC

Touchscreen Display for home automation system - FCC ID R33C4TT10 - Snap One, LLC
R33C4TT10

Touchscreen Display for home automation system

Jan 26, 2016

Equipment Class

DTS - Digital Transmission System
Controller for home automation system - FCC ID R33C4EA1 - Snap One, LLC
R33C4EA1

Controller for home automation system

Jan 25, 2016

Equipment Class

DTS - Digital Transmission System
WIFI MODULE - FCC ID R33C4LGWM - Snap One, LLC
R33C4LGWM

WIFI MODULE

Mar 24, 2015

Equipment Class

DTS - Digital Transmission System
Remote control - FCC ID R33C4SR260 - Snap One, LLC
R33C4SR260

Remote control

Mar 18, 2015

Equipment Class

DTS - Digital Transmission System
THERMOMETER - FCC ID R33C4THERM - Snap One, LLC
R33C4THERM

THERMOMETER

Feb 09, 2015

Equipment Class

DTS - Digital Transmission System