Cylindrical Style EMI Filters
BK Series – .375/.410 Dia. – Button Hermetically Sealed
Circuits Available – C & L
APPLICATIONS
The BK series offers effective filtering
from 500 KHz to 10 GHz. Glass sealed
for hermeticity, this low profile series is
impervious to high moisture, solvents, or
other severe environmental conditions
commonly encountered in military appli-
cations. It is designed for bulkhead
mounting in a slotted hole with nut and
lockwasher supplied. This series is ideal
for low to medium impedance circuits
where large amounts of capacitance to
ground can be tolerated. In the “L”
section version an internal ferrite bead
element provides both inductance and
series resistance (lossy characteristic)
which improves insertion loss and pro-
vides superior transient performance.
Alternate lead configurations or special
capacitance values may be ordered.
Custom packages or filter arrays utilizing
the BK series can be furnished.
CHARACTERISTICS
• .410 Dia. version (AK) meets or exceeds
the applicable requirements of MIL-F-
28861/1. See QPL listings.
• Internal ferrite bead provides inductance
for the L-section version.
• High DC current rating: 15 Amps
• Glass hermetic seal on both ends.
SPECIFICATIONS
1. Case/Terminal Plating:
STANDARD CONFIGURATION
Electro-tin standard – Silver or gold
available
2. Material:
Case: Brass standard – Steel available
End Seal: Mild steel
.070 .010
(2 PLC)
.250-28 UNF-2A (1/4-28)
.050
.375 DIA.
.010
ALT. .410 DIA. MAX.
See Note 4
Terminals: Nickel-iron alloy
3. Operating Temperature Range:
-55°C to +125°C
4. Electrical Characteristics:
A. Rated Voltage: See chart
B. Insulation Resistance:
.115
REF.
.200
.010
.190
MAX
.160
MAX.
.170
.010
At 25°C: 1,000 megohm-microfarad
min., or 50,000 megohms,
whichever is less, at the rated
DC voltage
*
.010
* = A FOR .187 THREAD
B FOR .312 THREAD
(See Note 1)
At 125°C: 100 megohm-microfarad
min., or 5,000 megohms,
CIRCUIT DIAGRAMS
whichever is less
C. Dielectric Withstanding Voltage (DWV):
R-level designs:
THRD
END
L2
2.0 times rated DC voltage
Class B, Class S designs:
2.5 times rated DC voltage
D. Capacitance: Values listed in chart are
“guaranteed minimum value” (GMV)
5. Marking:
Standard Marking: AVX, AVX part number,
lot code
BK2 only: Letter “L” denotes ferrite bead
inductor at threaded end
C
BK1
BK2 (See Note 2)
Notes:
millimeters (inches)
.25 (.010) 4.75 (.187)
1.27 (.050) 4.83 (.190)
1.78 (.070) 5.08 (.200)
2.92 (.115) 7.93 (.312)
3.81 (.150) 9.53 (.375)
1. Thread length option. Standard
part numbers shown (e.g.,
BK1CA-103) are .187" thread
length. Optional .312 length
available. (e.g., BK1CB-103).
3. Metric equivalent dimensions
given for information only.
4. .410 Dia. (identified as AK) is
required for all hi-rel tested
parts (e.g., MIL-F-28861/1
series).
2. Ferrite bead inductor at thread-
ed end (BK2 only).
See Reliability Codes section for definition of
Reliability Level marking. See How to Order
section for part number construction.
6. Installation:
4.32 (.170)
—
—
(See Note 3)
(See Note 1)
A. Mounting Torque:
44 oz-in. 4 oz-in.
B. Refer to “Installation, Handling, Hardware
Options” section of the catalog.
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