Add $50.00 for FREE shipping
Up to 20% Off Insteon Starter Kits!Free Shipping On Orders $50 And Up
Alert System Type
Driveway Alert
Entry Alert
Motion Alert
Sensor Type
Vehicle / Driveway
Infrared (IR)
Radio Frequency (RF)
Battery Operated
Outdoor Rated
Ease of Installation
Beginner (Installs < 10 minutes)
Other Ways to Shop
Customer Favorites
In Stock
On Sale
Order the Smarthome Catalog

Wireless Infrared Transmitter Sends Signals up to 2,000 Feet to your Optex Wireless 2000 or 1000 Receivers
Optex TD-20U Indoor/Outdoor Wireless Infrared Transmitter
Optex TD-20U Indoor/Outdoor Wireless Infrared Transmitter
Optex TD-20U Indoor/Outdoor Wireless Infrared Transmitter
Item# 7136ST
Price: Normally $90.00 
Hot Deal $66.97
Free shipping on orders over $50 - See Details


  • 2000 ft. line-of-sight transmission range
  • Uses passive infrared to detect motion and send RF signals to receivers
  • Weatherproof housing (IP54 rating) for both indoor and outdoor use
  • Selectable 50 foot Long Range or 17 foot Fan (Wide) detection pattern

Essential Info

The Optex TD-20U Indoor/Outdoor Wireless Infrared Transmitter is an accessory that enhances the effectiveness of Optex Wireless 1000 and 2000 systems. With a built-in infrared sensor, this wireless transmitter sends alarm signals to an Optex receiver placed up to 2,000 feet away.

The transmitter has a Fan and Long Range Beam setting for the infrared sensor. The Fan setting is ideal for door or entrance ways, or even as a motion sensor mounted in the corner of a room; and tracks motion with a wide 17 foot detection range. The Long Range Beam setting is ideal for wide driveways, parking lots, or even as a perimeter sensor for your property; and tracks motion with a 50 foot detection range.


What's Included

  • 1x - Indoor/Outdoor Wireless Infrared Transmitter

  • Specifications

    Manufacturer Optex
    Manufacturer Product No. TD-20U
    UPC 788924040226
    Weight0.4 pounds (6.3 ounces) (180 grams)
    Detection MethodPassive Infrared
    Detection AreaLong Range Beam: 50 feet (15 meters)

    Fan Pattern:17 feet (5 meters)
    Angle Adjustment± 45° Vertically and ± 5° Horizontally OR ± 5° Vertically and 45° Horizontally
    Status IndicatorRed LED
    Power Source9V Alkaline Battery
    Battery LifeApproximately 2 years [250 times per day at 70°F (20°C)]
    Operating Temperature15°F ~ 120°F (-10°C ~+50°C)
    Installation LocationOutdoor / Indoor
    Manufacturer Warranty 2-year limited warranty


    34 Ratings
    5 star: 79%  (27)
    4 star: 12%  (4)
    3 star: 3%  (1)
    2 star: 3%  (1)
    1 star: 3%  (1)
    Average Customer Rating
    (34 customer ratings)
    Share your thoughts with other customers
    MICHAEL -- kaufman, TX   5/1/2014
    After having some security issues that mandated motion sensors I bought three of these units to replace another popular/competitive sensor that failed to achieve it's advertised potential. These Optex sensors are great. They have a good, usable distance, especially if set on the beam setting, and don't produce a lot of false alarms. They will pick up birds or small game if placed in an area of activity or on the ground but set at 12-24 inches above the ground they work great. The beam will catch anything out to about 60 feet and the fan setting is good to about 18 feet. So far all good.
    RICHARD A -- sacramento, CA   4/3/2014
    Sensitive, clean design, easy to install, and I didn't even need to replace my previous version which has lasted 15+ years (so long I've lost track!)
    KAKI -- mountain brk, AL   8/29/2013
    Great product. Works really well!!!
    CATHERINE -- lawrenceville, GA   8/29/2013
    Product as described -
    RONNIE -- trinity, NC   6/23/2013
    All good worked just like it should have and delivered on time. Thanks
    DANIEL -- woodstock, GA   5/30/2013
    Replacement for a transmitter bought years ago and damaged by squirrels. Easy to set up. Linked with both of my existing receivers. Requires batteries about twice per year - otherwise no adjustments or maintenance necessary. The earlier model did not work well in the rain. This one seems to work fine in all weather. Overall an excellent product.
    TAMERA -- portsmouth, RI   5/6/2013
    Easy to link with the system. Best we have found.
    NORMAN -- port jefferson, NY   2/28/2013
    Works exactly as described.
    STEPHEN F -- rio rancho, NM   12/8/2012
    This item arreive in just 2 days, and is exactly what I needed. It is a replacement for a 10 year old model, and works perfectly.
    LOREN -- leesburg, OH   11/24/2012
    Got here quickly!
    ELENA -- freeport, NY   10/11/2012
    very happy with our order! Works great
    JAMES -- cresco, PA   9/30/2012
    Seems to work as advertised. Doesn't look like should be outdoors.Cheap construction, not waterproof. Put it in some kind of weatherproof container with an open front or it may not last long.
    DOW -- fairburn, GA   7/16/2012
    I received my product
    VICTOR -- hampstead, MD   7/8/2012
    The.This product is very reliable and easy to configure. This is the second motion that has been added to our loation. The first unit has performed flawlesly in all types of weather. A great security asset to our property.We are considering adding a third unit
    PAUL -- richmond, IN   1/19/2012
    Doesn't send signal when face of unit is wet....??? Otherwise, feel safer when I know there is someone/something around.
    JACK -- hillsboro, TX   1/19/2012
    While their ability to transmit signals long distance is great, their sensitivity or range was dissappointing.
    O'NEIL -- elk point, AB   1/5/2012
    Works great
    PAUL -- richmond, IN   6/23/2011
    Had to call Optex Tech Support to sync the receiver with the detector. Unit works well now.
    RYAN -- castro valley, CA   4/8/2011
    Very good range. False alarms from pets a problem so set unit up to PET ALLEY mode when used outdoors and point diagonally. Vertical aiming is good over doorways or where there are NO PETS. Do not put in direct sunlight where trees or bushes create a shadow on the lens or you will get false alarms. Correct set up and placement is very important with this unit to reduce false alarms. I played with placement for about a week to get it fine tuned. (Only put one screw in the unit when mounting until you are sure its in a good place) Very good quality product. Have been getting about 16 months on 1 9V battery. Battery low indicator sound is a huge PLUS! Highly recommend unit.
    MILTON -- rapid city, SD   3/10/2011
    We are very happy with this product. We use it in our Storage business. Great reception in most weather conditions and a great variety of adjustments for different locations and applications.

    Related Items

    Customers Also Bought

    Sign-up for Exclusive Email offers 
    How to Order Track Your Package Shipping Returns Contact Us Customer Service Retail Store
    Getting Started Learning Center FAQ Dealers Customer Testimonials Affiliate Program
    About Us INSTEON Press Awards Employment Guarantees Security & Privacy
    Free Catalog Email Newsletter Forum RSS Site Map
    Have questions? Call us at 800-762-7846 (Mon-Fri 5am-7pm and Sat 6am-3pm PT) or send us a message
    Place your order by 3pm PT for same day shipping
    Copyright 1995-2014 SMARTHOME™
    Verisign Secure Site PayPal Acceptance Mark