EC14 Trimmer Capacitor Equivalent & Substitute Parts

Part Overview

The EC14 is a 0.8–14pF air dielectric trimmer capacitor rated for 125V operation with top-side adjustment and through-hole mounting. Manufactured by Knowles Voltronics, this component is classified as obsolete. Due to its discontinued status, identifying functionally compatible substitute parts is essential for design continuity, repair, and legacy system support. Substitute parts must maintain electrical performance within the specified capacitance range, voltage rating, and physical form factor while accommodating minor adjustments in adjustment type and mounting configuration where applicable.

Substiute Parts

EC14

Knowles VoltronicsIn Stock: 1008EC14 Datasheet

Current PartRFQ

GAA14008

Sprague-GoodmanIn Stock: 1242GAA14008 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the EC14 is evaluated based on the following criteria:

Electrical Compatibility:

• Capacitance range must include or exceed 0.8–14pF
• Voltage rating must be ≥125V
• Dielectric material must be air (ensures equivalent Q factor and temperature stability)

Mechanical Compatibility:

• Physical diameter must be 0.300" (7.62mm) or compatible with existing footprint
• Height must not exceed 0.500" (12.70mm) to avoid assembly interference
• Mounting type (through-hole or user-defined) must accommodate existing PCB design

Environmental Compatibility:

• Operating temperature range must encompass –65°C to 125°C

The substitute part GAA14008 (Sprague-Goodman AIRTRIM® GAA series) meets these criteria with the following trade-offs:

• Capacitance range: 1–14pF (lower minimum, but covers the operational range above 1pF)
• Voltage rating: 250V (exceeds requirement)
• Adjustment type: Bottom (differs from top adjustment; requires design review for accessibility)
• Mounting type: User-defined (flexible integration)
• Physical dimensions: 0.303" Dia × 0.500" Max Height (compatible)
• Q factor: 5000 @ 100MHz (superior performance)

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute: GAA14008 (Sprague-Goodman AIRTRIM® GAA)

The GAA14008 is the designated manufacturer-recommended substitute for the EC14. Selection is justified on the following grounds:

• Electrical Performance: Capacitance range (1–14pF) covers the operational band above 1pF; voltage rating (250V) provides a 2× safety margin over the original 125V specification.
• Dielectric Equivalence: Air dielectric ensures identical temperature stability and Q factor characteristics.
• Physical Compatibility: Diameter (0.303") and height (0.500") are functionally equivalent to the original part.
• Environmental Compliance: RoHS compliance of the substitute supports modern manufacturing and regulatory requirements.
• Performance Enhancement: Q factor of 5000 @ 100MHz exceeds the original 3000, indicating superior dielectric quality.

Design Considerations:

The primary difference is adjustment type: the EC14 features top adjustment, while the GAA14008 features bottom adjustment. This requires verification that the PCB layout and assembly process accommodate bottom-side access. For applications where top adjustment is mandatory, alternative substitutes or custom integration may be necessary.

Both parts are obsolete; inventory availability should be confirmed with component distributors before design finalization.

Frequently Asked Questions (FAQ)

Q: Can the GAA14008 directly replace the EC14 without PCB modification?

A: Physical and electrical compatibility is high. However, the adjustment type differs (bottom vs. top). If the original design requires top-side access for tuning, PCB layout modification may be necessary. Verify that the bottom adjustment mechanism does not interfere with adjacent components or assembly fixtures.

Q: What is the significance of the capacitance range difference (0.8–14pF vs. 1–14pF)?

A: The EC14 minimum is 0.8pF; the GAA14008 minimum is 1pF. For applications requiring tuning below 1pF, the substitute is not suitable. For most general-purpose trimmer applications, the 1pF minimum is acceptable. Confirm the minimum capacitance requirement in the circuit design.

Q: Why is the voltage rating of the GAA14008 (250V) higher than the EC14 (125V)?

A: Higher voltage ratings provide design margin and reduce the risk of dielectric breakdown under transient overvoltage conditions. This is a beneficial characteristic and does not compromise performance at the original 125V operating point.

Q: Are there any RoHS or environmental compliance differences?

A: The GAA14008 is RoHS compliant; the EC14 compliance status is not specified. For applications subject to RoHS regulations, the GAA14008 is the preferred choice.

Q: Both parts are obsolete. How do I ensure long-term availability?

A: Consult authorized component distributors for current inventory levels. Consider qualifying multiple substitute parts or evaluating modern trimmer capacitor alternatives from active manufacturers. Document the substitution decision and maintain records for future reference.

Q: What is the difference between "Through Hole" and "User Defined" mounting types?

A: Through-hole mounting specifies a standard PCB integration method with leads passing through drilled holes. "User Defined" indicates flexible mounting options, including through-hole configuration. The GAA14008 can be integrated using through-hole methods compatible with the original EC14 footprint.

Q: How do I verify that the GAA14008 is suitable for my specific application?

A: Confirm that the following parameters align with your circuit requirements: capacitance range (1–14pF), voltage rating (≥125V), operating temperature (–65 to 125°C), and adjustment accessibility (bottom-side). If all parameters are satisfied, the substitute is electrically and mechanically compatible.