ET14 Trimmer Capacitor Equivalent & Substitute Parts

Part Overview

The ET14 is a 0.8–14pF trimmer capacitor manufactured by Knowles Voltronics, designed for top panel mount applications with a rated voltage of 125V. This component features an air dielectric, sealed construction, and operates across the temperature range of –65°C to 125°C. The ET14 is classified as obsolete, making identification of compatible substitute parts essential for ongoing system support and component procurement.

Substiute Parts

ET14

Knowles VoltronicsIn Stock: 1011ET14 Datasheet

Current PartRFQ

AT14

Knowles VoltronicsIn Stock: 1179AT14 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the ET14 is determined by the following critical parameters:

• Capacitance Range Compatibility: The substitute must cover the required tuning range. The ET14 operates from 0.8–14pF; the AT14 operates from 1–14pF. The AT14 minimum of 1pF represents a 0.2pF offset from the ET14 minimum, which may be acceptable depending on circuit tolerance requirements.
• Voltage Rating: Both parts are rated at 125V, ensuring electrical equivalence under specified operating conditions.
• Adjustment Type & Mounting: Both parts feature top adjustment and panel mount configuration, ensuring mechanical and operational compatibility.
• Physical Dimensions: The ET14 measures 0.300" diameter (7.62mm) with a maximum seated height of 0.480" (12.19mm); the AT14 measures 0.280" diameter (7.11mm) with identical height. The dimensional difference must be evaluated for mechanical fit in the target application.
• Operating Temperature Range: Both parts operate across –65°C to 125°C, providing thermal equivalence.
• Q Factor: Both parts maintain Q of 3000 @ 100MHz, ensuring equivalent RF performance characteristics.

Parameter Comparison

Engineering Selection Recommendations

The AT14 is an active production substitute for the obsolete ET14. Both parts are manufactured by Knowles Voltronics and share identical electrical performance characteristics, including voltage rating, Q factor, and operating temperature range. The AT14 is ROHS3 compliant, providing regulatory advantage for new designs and procurement cycles.

The primary engineering consideration is the capacitance range offset: the AT14 minimum of 1pF versus the ET14 minimum of 0.8pF introduces a 0.2pF difference. This offset must be evaluated against circuit tuning requirements and tolerance specifications. The physical diameter reduction from 0.300" to 0.280" requires mechanical fit verification in the target application, though seated height remains identical at 0.480".

The dielectric material change from air to PTFE does not affect the electrical performance parameters provided but may influence long-term stability characteristics in specific environmental conditions.

Frequently Asked Questions (FAQ)

Q: Can the AT14 directly replace the ET14 in existing designs?

A: Electrical substitution is feasible based on matching voltage rating, Q factor, and operating temperature range. Mechanical fit must be confirmed due to the 0.020" (0.51mm) diameter reduction. The 0.2pF capacitance range offset at minimum tuning must be evaluated against circuit tolerance requirements.

Q: What is the significance of the dielectric material change from air to PTFE?

A: Both dielectric materials are suitable for trimmer capacitor applications. The PTFE dielectric in the AT14 provides sealed construction characteristics. The electrical performance parameters (Q factor, voltage rating, temperature range) remain equivalent between the two parts.

Q: Why is the ET14 listed as obsolete?

A: The ET14 has been discontinued by the manufacturer. The AT14 represents the active production equivalent from Knowles Voltronics and is recommended for new procurement and design implementations.

Q: Does the AT14 meet current regulatory requirements?

A: Yes. The AT14 is ROHS3 compliant, meeting current environmental and regulatory standards for electronic component manufacturing and distribution.

Q: Are there dimensional constraints for panel mount installation?

A: Both parts are designed for panel mount configuration with identical seated height of 0.480" (12.19mm). The AT14 diameter of 0.280" is 0.020" smaller than the ET14. Verify that the mounting aperture accommodates the AT14 diameter specification.