TDK Model CU522a is a RF circulator/isolator designed to route signals in a single, fixed direction while isolating preceding stages from reflected signals.
Key Functions
  • Protects the Transmitter: If an antenna is damaged, iced over, or improperly matched, it creates a high Voltage Standing Wave Ratio (VSWR), causing RF energy to reflect backward. The circulator routes this dangerous reflected power away from the delicate final power transistors and into a terminating load.
  • Acts as an Isolator: When the third port of a circulator is connected to a matched 50-ohm load, it functions as an RF isolator. This absorbs reflected waves completely, preventing the reflected power from re-entering the transmitter output stage, which avoids distortion and equipment failure.
  • Impedance Matching: It provides a constant, stable load impedance for the FM transmitter, ensuring that the power amplifier operates at maximum efficiency and stability regardless of external antenna conditions. 
How the Ports Work
A standard 3-port circulator routes signals sequentially:
  • Port 1: Connected to the FM Transmitter's power amplifier.
  • Port 2: Connected to the Antenna.
  • Port 3: Connected to a 50-ohm Dummy Load.
A forward signal from the transmitter (Port 1) travels only to the antenna (Port 2). Any reverse energy bouncing back from the antenna (Port 2) is automatically routed to the dummy load (Port 3), where it is safely dissipated as heat. 
Frequency Range: 88-108 Mhz. 

Connectors: N-Type Female. All three connectors are in excellent condition. 

Size: 3-1/2 x 3-1/2 x 1-1/2 Inches

NOTE >>> There is no dummy load included. Also I have no spec sheet so I'm not sure about the power rating. 
I'm thinking 150- 200 watts on the FM Band ?  

Used. Has some wear. Overall looks good. SEE PICS ! 

International Shipping ? No problem !

Buy for $350.00 + $12 Shipping/Insurance 

Thanks for your interest. 

Jeff/scram  

Member since: Jul-04-98 in United States
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