The JRC NRG-98 is the Receiver (RF Front-End) module typically housed within the scanner unit of JRC marine radars, such as the JMA-9000 series. It is a critical component that handles the transition from high-power transmission to sensitive signal reception.

1. NRG-98 Receiver Unit

The NRG-98 is the “bucket” that contains the sensitive microwave components. In a radar system, this unit is responsible for taking the weak echo signals from the antenna and down-converting them into intermediate frequency (IF) signals that the display can process.

• Main Function: Signal amplification and frequency mixing.

• System Context: Primarily found in 25kW X-Band radars (like the JMA-9122 or JMA-9252).

2. NJS6926 Microwave Diode Limiter

Similar to the NJS6930 discussed earlier, the NJS6926 is the “shield” for the receiver.

• Purpose: It prevents the high-power pulse from the magnetron (transmitter) from entering and destroying the sensitive S-RX24 module.

• Note: While the NJS6930 is common in newer 8kW–10kW sets, the NJS6926 is often the specific variant used in higher-power 25kW scanner units.

3. S-RX24 (0636) MIC Front-End

The S-RX24 (often labeled with a secondary code like 0636 or paired with a CAE-333 PCB) is the Microwave Integrated Circuit (MIC).

• Role: This is the Low Noise Front-End (LNFE). It contains the local oscillator and the mixer.

• Sensitivity: This is the most delicate part of the radar. If your radar has “blind spots” or the range has significantly decreased, the S-RX24 is the most likely component to have failed (often due to a failing limiter or a magnetron “misfire”).