SPECIFICATIONS
GENERAL
Performance specifications are nominal unless otherwise specified and are subject to
change without notice.
Genera
l
Frequency Range
Operation mode
Power Supply
Weight (excluding batteries)
System hum and noise
Microphone
TRANSMITTER
RF Output
Spurious & Harmonics
Modulation
Frequency Stability
Voice Compressor
VOX Threshold
VOX Characteristics
Current Draw
RECEIVER
Rece
iv
er Circuit
Sensitivity
Modulation Acceptance
Selectivity
Spurious & Image
lntermod Response
Frequency Stability
Current Draw
72-76 MHz Std. (Other frequencies are available by
special request.)
Simplex, Duplex or Repeating (model specific)
9V Alkaline Battery, NEDA 1604A or Earmark RPS
Approximately 26 Oz.
-50 dB
Electret, 10 kOhm
100 mW, 50 Ohm
75 dB
16K0F3E
0.005% @ (-30 c• to +50 C
0
)
Attack, <1 ms; Decay, 130 ms
6 dB below full modulation
Attack, <1 ms; Delay, 750 ms
45 mA, ON; 3 mA, standby (VOX)
Dual conversion, 1st IF Frequency 10.7 MHz, 4 Pole Quartz
Filter; 2nd IF 455 kHz, 4 Pole Ceramic Filter
0.4 uV for 12 dB quieting
20 kHz
-55 dB @ 40 kHz from center frequency
-47 dB
-70 dB
0.005% @ (-30 c• to +50 C
0
)
10 mA
APPROVALS AND AUTHORIZATIONS
FEDERAL COMMUNICATIONS COMMISSION
All Headsets have been type accepted and certificated by the FCC for operation in Part 90 (Private Land
Mobile Services) in the 72-76 MHz band. All transmitters, including Repeater Stations operate in the 72-
76 MHz band with a power of 100 mW and modulation characteristics 16K0F3E. Type approval numbers
are located on each unit. FCC rules require licensing by the purchaser. Requests for application
forms or information may be obtained from the FCC, Gettysburg, PA 17325.
UNDERWRITER'S LABORATORY LISTING
EARMARK Communication Headsets are UL listed for Intrinsic Safety as follows:
Series 4 & 4W Class I, Division I, Group C & D;
Non-lncendive: Class I, Div. 2, Gr. A, B, C and D
Series 4W
Class II, Group E, F & G; Class Ill.
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INSTALLING THE EARMARK RPS
To install the Earmark Rechargeable Power System, loosen the two knurled nuts and lift
off the Battery Cover Plates on either side of the Headset. Install the Battery Box
Extenders by threading them onto the exposed screws on each side of each Battery Box.
Insert the Rechargeable Power Packs and secure them with the New Battery Cover
�-
Your Headset will function equally well with either the alkaline batteries or the Earmark
Rechargeable Power Systems. The only difference will be the time available between
battery changes. The following chart shows the
APPROXIMATE
operating times you may
expect from various models and battery combinations.
MODE
Power
9V Alkaline
8.4V (NiMh)
EARMARK
Condition
Rechargeable
RPS (NiCd)
Continuous
HI
18
4.5
9
Live Mic
LO
25
6.0
12
Push-to-talk
HI
60
14
28
LO
84
20
40
B. COMFORT FEATURES
1. Vertical StabUlzer Strap
The Earmark Series 4C Headset is most comfortable when worn with the
Vertical Stabilizer Strap. The wide strap distributes the Headset's weight over
the greatest possible area and guarantees optimum comfort. You can move the
Headband Pad from the Headband onto the Vertical Stabilizer Strap for even
more comfort. Set the strap so the top of your ear just clears the inside of the
earmuff. Lock
it
in place with the buckle. This setting will also provide good
clearance for your shoulder, under the muff.
2.
Back Support Strap
Adjust the Back Support Strap so that it fits gently against the back of the head
and prevents the Headset from falling forward when you bend over.
C. EARMUFFS
Your Earmark Headset comes with hypo-allergenic, noise cancelling earmuffs.
These are special earmuffs for your Series 4C Headset. They are fabricated of
polyurethane and are exceptionally durable.
If you are using the NVM (no visible microphone), please read the following:
The transmitter earmuff contains the microphone. You can feel it at the bottom of the
earmuff surface. Putting other earmuffs or cooling devices on the Headset will cause
a reduction in your overall transmission quality. If you want to use a moisture
absorbing pad over the earmuff, cut out the piece of the pad that covers the
microphone.
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