Specifications
STUDIO EQUIPMENT
ALLEN AVIONICS
900
HUM ELIMINATORS
RF transmission in cables is routinely plagued by 50Hz or 60Hz hum or other interference.
When a cable is used for video signals, small electrical currents caused by differences in
ground potential (ground loops) or induced common-mode noise, can result in
considerable hum interference. Cameras, video recorders, monitors and video effects
generators... even switchers and computers downstream... are affected. Allen Avionics
offers three types of products to eliminate hum caused by ground loops or induced
currents. All are broadcast quality. Although they can be inserted anywhere in the
transmission system, they are most effective at or near the end of the cable run.
www.bhphotovideo.com
PHOTO - VIDEO - PRO AUDIO
◆ Flat response
◆ Bandwidths up to 30MHz (100 MHz on the
HEC-5000)
◆ For color and B&W
◆ No low frequency or high frequency roll-off
◆ No differential gain distortion
◆ No differential phase distortion
◆ Passive device-failure free
◆ Reversible
◆ Rugged, waterproof case
◆ Small, compact package
◆ Use in the field between remote truck; telco
and microwave; for intertruck hookup
◆ Use in the studio between buildings; on long
runs in buildings; between studios and trans-
mitters; incoming/outgoing telco circuits
HEC-500:
50 Ohms unbalanced (impedance), 50dB for 60Hz hum reduction
depending on system, 0.2dB maximum insertion loss, 20dB minimum
return loss. Made of high-impact ABS plastic, measures 5
3
⁄8 x 4 x 2”
(HxWxD) and weighs 2.5 lbs.
(Mfr # HEC500 • B&H # ALHEC500) ..................144.95
HEC-1000:
75 Ohms unbalanced (impedance), 50dB for 60Hz hum reduction
depending on system, 0.2dB maximum insertion loss, 20dB minimum
return loss. Made of high-impact ABS plastic, measures 5
3
⁄8 x 4 x 2”
(HxWxD) and weighs 3.5 lbs.
(Mfr # HEC1000 • B&H # ALHEC1000)..............139.95
HEC-2000:
75 Ohms unbalanced (impedance), 60dB for 50Hz or 60Hz hum
reduction depending on system, 0.2dB maximum insertion loss, 20 dB
minimum return loss. Made of die-cast metal, measures 4
11
⁄16 x 3
11
⁄16 x
2
1
⁄16” (HxWxD) and weighs 3.5 lbs. (Mfr # HEC2000 • B&H # ALHEC2000) ....149.95
HEC-2000-H:
Same as above, except designed for optional rack mounting installation.
A heavy-duty version, 1/4” thick, stainless steel guard rails to protect the
connectors when not in use.
(Mfr # HEC2000H • B&H # ALHEC2000H)..........169.95
HEC-2000-V:
Heavy-duty version, 1/4” thick, stainless steel guard rails protect
connectors when not in use.
(Mfr # HEC2000V • B&H # ALHEC2000V) ..........174.95
HEC-3000:
75 Ohms unbalanced (impedance), provides 3 channels of 60dB for
50Hz or 60Hz hum reduction depending on system, 0.2 dB maximum
insertion loss, 20dB minimum return loss. Provides 70dB isolation
between channels. Made of die-cast metal, measures 7
1
⁄16 x 4
3
⁄4 x 3
1
⁄16”
(HxWxD) and weighs 10 lbs.
(Mfr # HEC3000 • B&H # ALHEC3000) ........................................................................399.95
HEC-4000:
GBR unbalanced (impedance), Sync balanced, provides 3 channels of
60dB for 50Hz or 60Hz hum reduction when used in RGB or YUV
systems, plus one channel of transformer isolation. 0.2dB maximum
insertion loss, 20dB minimum return loss. Provides 70dB isolation
between channels. Made of die-cast metal, measures 7
1
⁄16 x 4
3
⁄4 x 3
1
⁄16”
(HxWxD) and weighs 10 lbs.
(Mfr # HEC4000 • B&H # ALHEC4000) ........................................................................519.95
HEC-5000:
75 Ohms unbalanced (impedance), provides 5 channels of 60 dB per
channel hum reduction. 0.2dB maximum insertion loss, 20dB minimum
return loss. Provides 70dB isolation between channels.
The HEC-5000 has a bandwidth of over 100 MHz making it suitable for
HDTV applications and many video projection systems with 100 MHz
bandwidths. Made of die-cast metal, measures 7
1
⁄16 x 4
3
⁄4 x 3
1
⁄16” (HxWxD)
and weighs 10 lbs.
(Mfr # HEC5000 • B&H # ALHEC5000 )........................................................................594.95
Hum Eliminators
Hum eliminators work best in those circumstances where interference is cause by small differences in ground potential (less than 20v DC) or by
induced currents in long cable runs. When there are multiple power panels in a building, or even on a single floor, equipment and lighting loads result
in small differences in potential which induce ground loop current flow and 60Hz hum.
Electromagnetically-induced currents in long cable runs also create hum. For 50Hz and 60Hz power systems, and where induced currents are high,
HEC-2000 and HEC-2000-H increase the attenuation at the power frequency. Should a small amount of hum remain after an HEC has been added to
the circuit, a second HEC can be added in series, without significant degradaton of the video signal.