Pomona Electronics 73057 TNC Connector Plug Equivalent & Substitute Parts

Part Overview

The Pomona Electronics 73057 is a TNC connector plug designed for 50-ohm coaxial cable applications. This straight-mount, male-pin connector features crimp termination and is rated for frequencies up to 6 GHz. The part is currently classified as obsolete, making equivalent and substitute parts necessary for ongoing system maintenance and new designs requiring compatible RF connectivity solutions.

Substiute Parts

73057

Pomona ElectronicsIn Stock: 117473057 Datasheet

Current PartRFQ

73054

Pomona ElectronicsIn Stock: 95373054 Datasheet

MFR RecommendedRFQ

73056

Pomona ElectronicsIn Stock: 97273056 Datasheet

MFR RecommendedRFQ

31-320-RFX

Amphenol RFIn Stock: 256431-320-RFX Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the Pomona Electronics 73057 is determined by the following critical parameters:

Primary Compatibility Criteria:

• Connector style (TNC vs. alternative connector types)
• Impedance rating (50 Ohms)
• Connector type (Plug, Male Pin)
• Mounting configuration (Free Hanging/In-Line)
• Contact termination method (Crimp)
• Frequency capability (minimum 6 GHz)
• Fastening type (Threaded)

Substitute Classification:

Direct Equivalents (MFR Recommended): Parts 73054 and 73056 maintain identical TNC connector style, 50-ohm impedance, male-pin configuration, and crimp termination. Both are active products from the same manufacturer, ensuring design continuity and compatibility with existing cable assemblies.

Similar Alternative (Different Connector Style): Part 31-320-RFX from Amphenol RF represents a different connector family (BNC instead of TNC). While it shares 50-ohm impedance, crimp termination, and free-hanging mounting, the BNC connector style and bayonet fastening differ fundamentally from the threaded TNC interface. This part is suitable only when system redesign to accommodate BNC connectors is acceptable.

Parameter Comparison

Engineering Selection Recommendations

For Direct Replacement (Recommended):

Pomona Electronics 73056 is the preferred substitute for the obsolete 73057. Both maintain identical TNC connector geometry, 50-ohm impedance, straight-mount configuration, and crimp termination. Part 73056 is an active product with ROHS3 compliance and extends frequency capability to 11 GHz, exceeding the original 6 GHz specification. Cable compatibility includes RG-58 and RG-141, which overlap with common applications. The inclusion of four components (connector, contact, ferrule, heat shrink) versus three in the original part provides additional assembly flexibility.

Pomona Electronics 73054 serves as an alternative when right-angle mounting is required. It maintains all electrical and mechanical compatibility with the 73057 while offering different physical orientation. This part is active and ROHS3 compliant.

For System Redesign Only:

Amphenol RF 31-320-RFX should be considered only when connector style change from TNC to BNC is acceptable. This part introduces a different fastening mechanism (bayonet lock versus threaded) and operates at a lower maximum frequency (4 GHz). Cable compatibility is broader, supporting RG-58 variants and additional cable types. This substitution requires mechanical redesign of mating interfaces and is not a direct plug-in replacement.

Frequently Asked Questions (FAQ)

Q: Can I use Pomona Electronics 73054 as a direct replacement for 73057?

A: Part 73054 is electrically compatible but differs in mounting orientation. The 73054 features right-angle mounting, while the 73057 is straight-mount. Use 73054 only if your application requires or can accommodate right-angle cable routing.

Q: What is the primary difference between 73056 and 73057?

A: Both are straight-mount TNC plugs with 50-ohm impedance and crimp termination. The 73056 is an active product with extended frequency capability (11 GHz versus 6 GHz) and supports different cable groups (RG-58, 141 versus RG-59, 62). The 73056 includes four components instead of three.

Q: Why is the Amphenol RF 31-320-RFX listed as a similar part rather than a direct equivalent?

A: The 31-320-RFX uses BNC connector style with bayonet fastening, fundamentally different from the TNC threaded interface of the 73057. While both are 50-ohm male-pin plugs, the connector mismatch prevents direct substitution without mechanical redesign of mating connectors and cable assemblies.

Q: Are all substitute parts ROHS3 compliant?

A: Yes. The main part (73057) and all listed substitutes (73054, 73056, 31-320-RFX) are ROHS3 compliant, meeting environmental and regulatory requirements for new designs and replacements.

Q: Which substitute part supports the widest frequency range?

A: Pomona Electronics 73056 supports frequencies up to 11 GHz, exceeding both the original 73057 (6 GHz) and the Amphenol RF alternative (4 GHz).

Q: Can I use these connectors with different cable types than specified?

A: Cable group specifications define the impedance-matched coaxial cables for which each connector is designed. Using connectors outside their specified cable groups may result in impedance mismatches and signal degradation. Adhere to the cable group designations provided for each part.