Compact 3-Element Ceramic IF Filter for Motorola Radio Receivers
This is a Motorola-specified three-element ceramic intermediate frequency (IF) filter used in various Motorola two-way radio models. The component is marked "55D8" with a circled "M" symbol and "J" designation on its black plastic housing, indicating it's manufactured by a specialist RF filter supplier to Motorola's specifications. This compact through-hole mount filter features three pins for PCB installation and provides intermediate frequency filtering in the radio's receiver chain. The visible internal construction shows encapsulated ceramic resonator elements designed for precise frequency response and stability.
Key Features
- Motorola-specified 3-element ceramic IF filter
- Compact black plastic housing with three through-hole mounting pins
- Component markings: "55D8", circled "M", and "J" designations
- Three-pin configuration for input, output, and ground connections
- Encapsulated ceramic elements for frequency stability
- Through-hole design for traditional PCB soldering
- Factory-tuned to precise IF specifications
Compatible Models
- Various Motorola two-way radios (consult service manual or parts diagram for specific model compatibility)
What's Included
- One (1) 3-Element Ceramic IF Filter
Application & Installation
This three-element ceramic IF filter is a precision RF component requiring professional installation by a qualified radio technician. The filter must be soldered into the radio's circuit board in the intermediate frequency section, where it provides bandwidth filtering and selectivity. Compared to six-element filters, this three-element design typically offers a broader bandwidth with less steep selectivity characteristics, making it suitable for applications requiring wider passbands or less stringent adjacent channel rejection. Replacement is necessary when the filter fails due to physical damage, thermal stress, or electrical breakdown, with symptoms including poor receiver sensitivity, broadband noise, distorted audio, or complete receive failure. Installation requires proper through-hole soldering techniques with careful heat management to prevent damage to the internal ceramic elements. The three-pin configuration must be oriented correctly according to the PCB layout to ensure proper signal flow from input to output. After installation, receiver alignment may be required using specialized RF test equipment to optimize performance and ensure the radio meets design specifications for sensitivity and selectivity.
Manufacturer Part Number: 9180098D06
Component Markings: 55D8, Ⓜ, J
Filter Type: 3-Element Ceramic IF Filter ("3 Wr" - 3 Wire/Element)
