NHRC NHRC-4/M2, Инструкция по установке и настройке

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NHRC-4/M2 User Guide
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2001, 2005, NHRC LLC. All Rights Reserved.
3.3
Using the Digital Output
The NHRC-4 Repeater Controller has a digital output that can be used for various remote
control applications or to control a fan on the repeater's transmitter. The digital output is an
open-drain into a power MOSFET, which is capable of sinking quite a bit of current, but we
recommend a maximum load of about 500 mA. Use a relay to drive larger loads. The open-
drain output can be used to gate the HOOKSWITCH signal to a TS-32 or other CTCSS
decoder, to enable or disable CTCSS. Software allows the output to be enabled, disabled, or
pulsed. In fan control mode, this output will be turned on when the transmitter is turned on,
and turned off a programmable amount of time after the transmitter is turned off.
3.4 Adjusting the Audio Levels
Audio Level Adjustments
Potentiometer Use
VR1 Primary Receiver Level
VR2 Secondary Receiver Mix Level
VR3 Primary Receiver Mix Level
VR4 Beep Tone Mix Level
VR5 Primary Transmitter Master Level
VR6 Secondary Transmitter Master Level
Preset all potentiometers to midrange. Key a radio on the primary input frequency, send
some touch-tones, and adjust VR1 (the primary receiver level) until DTMF decoding is
reliably indicated by yellow LED D5.
Note: If VR1 is set too high, a crackling noise may be heard in the transmitted audio during
the hang time. Reduce the level set by VR1 until this noise goes away. Any repeated audio
level reduction caused by adjusting VR1 can be compensated for by adjusting VR3 (primary
receiver level) or VR5 (primary transmitter output level.)
The primary radio's transmit deviation is set with VR5 (the primary transmitter master level)
on the controller board and the transmitter's deviation/modulation control. The key to
properly adjusting these controls is to remember that the limiter in the transmitter is
after
VR5 but probably before the transmitter's deviation/modulation control. The transmitter's
deviation/modulation control will set the actual peak deviation, and VR5 will set the level
into the transmitter. You do not want excessive limiting on normal speech going through the
repeater; it sounds bad and tends to "pump-up" background noise. On the other hand, some
limiting is desirable. An oscilloscope connected to the audio output of a receiver tuned to the
transmitter's frequency will show limiting as the audio gets "flat-topped" or clipped by the
limiter. Ideally, a 4.5KHz deviation signal input to the repeater should result in a 4.5 KHz
deviation output, and 5.5 KHz of input deviation should result in just under 5.0 KHz of
deviation out of the repeater. A service monitor (or two), deviation meter, and/or a signal
generator are necessary to do this job right.
The secondary radio's transmit deviation is set with VR2 (the secondary transmitter master
level). Enable the secondary transmitter, and adjust VR2 for proper transmit deviation,
similarly to VR5.