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Linear MegaCode ACT-21B Block Coded One Channel Mini Transmitter

Product Highlights:

• Compatible with all Linear MegaCode access controllers & receivers
• Supplied with quick-disconnect key ring
• Superior transmission range
• Factory programmed MegaCode format supports over 1,000,000 codes
• Two type 1616 Lithium batteries supplied
• 5-year battery service life
• Frequency: 318 MHz - Block coded
• 1 Week Lead Time
SKU: LIN-act-21b

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The Model ACT-21B 1-Channel Block Coded Key Ring Transmitter is designed for use with Linear’s access control products. The Model ACT-21B is a single-channel device supplied with a quick-disconnect key ring. Also included are lithium batteries with a five-year service life. A unique 10-second time-out feature prevents the system from being shut down by a single transmitter transmitting continuously.

The transmitter is MegaCode format, which means each transmitter is factory preprogrammed with one of over 1,000,000 codes, virtually eliminating the possibility of code duplication. Because the receiver ”learns” each specific code, no unauthorized person can gain access to the system by reprogramming a transmitter.

Block coded transmitters are factory programmed to a sequential series of transmitter ID codes. When used with a Linear access controller, transmitters can be locally or remotely programmed into memory by entering the first and last codes of the block into the system. Facility codes can be selected to further customize the system.

*All products require a 1 week lead time


Additional Info

Brand Linear
Manufacturer Part Number ACT-21B
Former Part Number N/A
Specifications N/A


Select Optional Accessories Below to Customize Your Equipment:

Showcased Accessories

  • All Products
  • Stand-Alone Keypads
  • Radio Remotes
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  • Hard-Wired Keypads

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