Circular connectors offer the capability to transmit power and electrical signals in multi-pin designs. They are easily installed and removed. Because of their cylindrical structure, they are sealed to provide the toughest performance in the harshest of applications. They have outstanding mechanical sturdiness and a higher strength-to-weight performance critical for high shock and vibration environments. EMI Filter Circular Connectors strip unwanted electromagnetic interference (EMI) or transient voltages from signal lines by incorporating ceramic capacitors. This type of connector provides effective EMI filtering, reducing the amount of real estate required within a product enclosure.
As a fully vertically integrated company, Spectrum Control is truly unique among connector suppliers. Spectrum Control’s filtered EMI connector offerings are fully vertically integrated and manufactured in the USA. Components including ceramic capacitors and shells are manufactured by our State College, PA facility, providing our customers with high-quality parts with the industry’s shortest lead times.
At Spectrum Control, we know it is rare to find an of-the-shelf connector that completely satisfies the environmental, mechanical, and electrical requirements of demanding, high reliability applications. Our engineering team is ready to modify one of these existing designs or start with a “clean sheet” to ensure our connector satisfies all of your requirements.
This premium line of custom circular EMI filtered connectors are completely intermateable with MIL-DTL-38999 Series III. Spectrum Control also offers custom circular connectors in an EMI filtered style, including MIL-DTL-55116, -83723, -24308, -26482, and -5015. Our filtered compact shell connectors provide an effective filtering device that reduces the amount of real estate required within a product enclosure. Using our expertise in EMI filter design and manufacturing, we offer planar-style filtered arrays available in C and Pi circuits. Other filter circuits, including transient protection, are available.
In addition, we can accommodate your quick-turn schedule for prototyping by adding either planar or tubular capacitor filtering to the rear of a standard connector.
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For even greater design flexibility, Spectrum Control offers composite shell circular connectors. These composite connectors feature shells fabricated from high grade thermoplastic and designed to replace traditional metal connector shells for substantial weight reduction. The composite shell maintains the form, fit and function of the original connector shell, making it ideal for applications where weight is a critical factor. A composite shell version of any Spectrum Control’s circular connector designs is available. |
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Our vertical integration includes a unique material process and extensive machining capabilities, allowing us to easily modify the mechanical package of any connector, ensuring fast and affordable custom designs. Other connector manufacturers mold their composite shells, making custom designs expensive. At Spectrum Control, custom mechanical variations are machined allowing for unique packages without traditional tooling charges. · Stainless steel, aluminum, composite shess for harsh environmental and weight sensitive appplication · Cadmium, nickel, black nickel zinc pating for military and RoHS envionments · AC and lightning withstand designs for transient environments (up to DO 160 Level IV) |
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Spectrum Control also has a family of hermetically sealed circular connectors that protect against changes in atmospheric pressure and exposure to humidity, grime, and chemicals, making them ideal for aerospace engine control, hydraulic, and caustic environments where harsh conditions could exist. The hermetically sealed connector’s receptacle has a seal of 10-7cm3 and comes in filtered and unfiltered versions. |
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Spectrum Control’s Mini-MIL circular connectors are small and lightweight offering space and weight savings while providing equivalent performance to standard MIL-DTL-38999 connectors. These connectors are available filtered with C, Pi or mixed capacitance, or unfiltered, with a range of engagement, termination and receptacle types. Mini-MIL connectors can be customized to satisfy various mechanical and electrical requirements and are ideal for military, industrial, and medical applications where space restrictions do not allow for larger 38999 connectors. |
Cap Code | Cap Value | Circuit |
---|---|---|
251 | 250 pF | C |
501 | 500 pF | C, Pi |
102 | 1,000 pF | Pi |
122 | 1,250 pF | C |
252 | 2,500 pF | C, Pi |
502 | 5,000 pF | C, Pi |
103 | 10,000 pF | C, Pi |
203 | 20,000 pF | Pi |
253 | 25,000 pF | C |
503 | 50,000 pF | Pi |
Note: Custom capacitance values and tolerances available. |
Shell Size | A | B | C | D | E | F | G Thread | H Thread | ![]() |
A(9) | .937 | .719 | .594 | .128 | .216 | .820 | .6250-0.1P-0.3L-TS | M12x1.0-6g 0.100R | |
B(11) | 1.031 | .812 | .719 | .128 | .194 | .820 | .7500-0.1P-0.3L-TS | M15x1.0-6g 0.100R | |
C(13) | 1.126 | .906 | .812 | .128 | .173 | .820 | .8750-0.1P-0.3L-TS | M18x1.0-6g 0.100R | |
D(15) | 1.220 | .969 | .906 | .128 | .194 | .820 | 1.0000-0.1P-0.3L-TS | M22x1.0-6g 0.100R | |
E(17) | 1.311 | 1.062 | .969 | .128 | .194 | .820 | 1.1875-0.1P-0.3L-TS | M25x1.0-6g 0.100R | |
F(19) | 1.437 | 1.156 | 1.062 | .128 | .194 | .820 | 1.2500-0.1P-0.3L-TS | M28x1.0-6g 0.100R | |
G(21) | 1.563 | 1.250 | 1.156 | .128 | .194 | .790 | 1.3750-0.1P-0.3L-TS | M31x1.0-6g 0.100R | |
H(23) | 1.689 | 1.375 | 1.250 | .154 | .242 | .790 | 1.5000-0.1P-0.3L-TS | M34x1.0-6g 0.100R | |
J(25) | 1.811 | 1.500 | 1.375 | .154 | .242 | .2790 | 1.6250-0.1P-0.3L-TS | M37x1.0-6g 0.100R |
Shell Size | A | B | C | D | E | F Thread | G Thread | ![]() |
A(9) | 1.189 | 1.063 | .9375 | .649 | .102 | .6250-0.1P-0.3L-TS | M12x1.0-6g 0.100R | |
B(11) | 1.374 | 1.252 | 1.0625 | .749 | .102 | .7500-0.1P-0.3L-TS | M15x1.0-6g 0.100R | |
C(13) | 1.500 | 1.374 | 1.250 | .936 | .102 | .8750-0.1P-0.3L-TS | M18x1.0-6g 0.100R | |
D(15) | 1.626 | 1.500 | 1.375 | 1.060 | .102 | 1.0000-0.1P-0.3L-TS | M22x1.0-6g 0.100R | |
E(17) | 1.752 | 1.626 | 1.4375 | 1.185 | .102 | 1.1875-0.1P-0.3L-TS | M25x1.0-6g 0.100R | |
F(19) | 1.937 | 1.811 | 1.5625 | 1.310 | .134 | 1.2500-0.1P-0.3L-TS | M28x1.0-6g 0.100R | |
G(21) | 2.063 | 1.937 | 1.750 | 1.435 | .134 | 1.3750-0.1P-0.3L-TS | M31x1.0-6g 0.100R | |
H(23) | 2.189 | 2.063 | 1.8125 | 1.560 | .134 | 1.5000-0.1P-0.3L-TS | M34x1.0-6g 0.100R | |
J(25) | 2.311 | 2.189 | 2.000 | 1.685 | .134 | 1.6250-0.1P-0.3L-TS | M37x1.0-6g 0.100R |
Shell Size | A | B | C | D | E Thread | ![]() |
A(9) | .858 | .748 | 1.220 | .724 | M12x1.0-6g 0.100R | |
B(11) | .984 | .862 | 1.220 | .830 | M15x1.0-6g 0.100R | |
C(13) | 1.157 | 1.027 | 1.220 | 1.000 | M18x1.0-6g 0.100R | |
D(15) | 1.279 | 1.153 | 1.220 | 1.129 | M22x1.0-6g 0.100R | |
E(17) | 1.405 | 1.291 | 1.220 | 1.267 | M25x1.0-6g 0.100R | |
F(19) | 1.515 | 1.397 | 1.220 | 1.374 | M28x1.0-6g 0.100R | |
G(21) | 1.641 | 1.523 | 1.220 | 1.500 | M31x1.0-6g 0.100R | |
H(23) | 1.787 | 2.641 | 1.220 | 1.618 | M34x1.0-6g 0.100R | |
J(25) | 1.889 | 2.767 | 1.220 | 1.744 | M37x1.0-6g 0.100R |
Contact Size | ØA | ØB REF | Recommended Solder Cup Wire Size | ![]() |
22D | .020±.002 | 0.056 | 22-26AWG | |
20 | .030±.002 | 0.076 | 18-22AWG | |
16 | .040±.002 | 0.100 | 14-18AWG | |
12 | .062±.002 | 0.145 | 10-14AWG |
Spectrum Control has been a leader in providing application specific EMI filtered connector solutions since its founding in 1968. Our brand offers the industry’s most extensive line of circular connectors that are designed for high reliability or demanding environmental applications such as commercial aviation and avionics, of highway and agricultural vehicles, high reliability power supplies, as well as all airborne, ship or ground-based military applications.
At Spectrum Control, we know it is rare to find an of-the-shelf connector that completely satisfies the environmental, mechanical, and electrical requirements of demanding, high reliability applications. Our engineering team is ready to modify one of these existing designs or start with a “clean sheet” to ensure our connector satisfies all of your requirements.