Codan Radio Communications AMP 4 470 User Manual

RF Exposure Warning

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Exposure to radio frequency (RF) energy has been identified as a potential environmental factor that must be considered before a radio
transmitter can be authorized or licensed. The FCC and IC have therefore developed maximum permissible exposure (MPE) limits for field
strength and power density, listed in FCC 47 CFR § 1.1310 and IC RSS-102 Issue 2 Sect 4. The FCC has furthermore determined that
determination of compliance with these exposure limits, and preparation of an Environmental Assessment (EA) if the limits are exceeded,
is necessary only for facilities, operations and transmitters that fall into certain risk categories, listed in FCC 47 CFR § 1.1307 (b), Table 1.
All other facilities, operations and transmitters are categorically excluded from making such studies or preparing an EA, except as indicated
in FCC 47 CFR §§ 1.1307 (c) and (d).

Revised FCC OET Bulletin 65 (Edition 97-01) and IC RSS-102 Issue 2 provide assistance in determining whether a proposed or existing
transmitting facility, operation or device complies with RF exposure limits. In accordance with OET Bulletin 65, FCC 47 CFR § 1.1307 (b)
and RSS-102 Issue Sect 2.5, the Codan Radio Communications transmitter manufactured in Canada is categorically excluded from routine
evaluation or preparing an EA for RF emissions and this exclusion is sufficient basis for assuming compliance with FCC/IC MPE limits.
This exclusion is subject to the limits specified in FCC 47 CFR §§ 1.1307 (b), 1.1310 and IC RSS-102 Issue 2 Sect 4. Codan Radio
Communications has no reason to believe that the excluded transmitter encompasses exceptional characteristics that could cause non­compliance.

Notes:

• The FCC and IC’s exposure guidelines constitute exposure limits, not emission limits. They are relevant to locations that • are
accessible to workers or members of the public. Such access can be restricted or controlled by appropriate means (i.e., fences,
warning signs and others).

• The FCC and IC’s limits apply cumulatively to all sources of RF emissions affecting a given site. Sites exceeding these • limits are
subject to an EA and must provide test reports indicating compliance.

RF Safety Guidelines and Information

Base and Repeater radio transmitters are designed to generate and radiate RF energy by means of an external antenna, typically mounted
at a significant height above ground to provide adequate signal coverage. To reduce potential radio interference to other users, the
antenna type and its gain should be so chosen that the equivalent isotropically radiated power (EIRP) is not more than that permitted for
successful communication. The following antenna installation guidelines are extracted from Appendix A from OET Bulletin 65 and must be
adhered to in order to ensure RF exposure compliance:

Non-building-mounted Antennas:

Height above ground level to lowest point of antenna ≥ 10 m

• Power ≤ 1000 W ERP (1640 W EIRP)

Building-mounted Antennas:
Power ≤ 1000 W ERP (1640 W EIRP)

The following RF Safety Guidelines should be observed when working in or around transmitter sites:

The minimum safe distance the user should be from the transmitter antenna while transmitting is 142 cm for transmitters 8W or

less and 300 cm for amplifiers 30W or less. This assumes a maximum antenna EIRP of 15 dBi.

• Do not work on or around any transmitting antenna while RF power is applied.

• Before working on an antenna, disable the appropriate transmitter and ensure a “DO NOT USE” or similar sign is placed on or

near the PTT or key-up control.

• Assume all antennas are active unless specifically indicated otherwise.

• Never operate a transmitter with the cover removed.

• Ensure all personnel entering a transmitter site have electromagnetic energy awareness training.

For more information on RF energy exposure and compliance, please refer to the following:

FCC Code of Regulations; 47 CFR §§ 1.1307 and 1.1310

• FCC OET Bulletin 65, Edition 97-01, “Evaluating Compliance with FCC Guidelines for Human Exposure to Radiofrequency
Electromagnetic Fields”

• http://www.fcc.gov/oet/rfsafety/
IC RSS-102 Issue 2, “Radio Frequency Exposure Compliance of Radio Communication Apparatus”

Power Amplifier AMP-4-470-30-00

1. General description.

The power amplifier (PA) is a one stage unit, working in AB-class operation mode. In addition to the
power amplifier section, the PA contains the power control, status monitoring and protecting circuitry,
as well as voltage regulation for supplying the RF and main control circuits.

The output power may be controlled either by the external analog signal (remote control), or by
potentiometer, accessible from the front panel (local control).

The voltage regulator turns on, when all four of the following conditions are present:

- remote control voltage (in the case of remote control) is greater than 1 V;

- input power is not less than 0.5 W;

- the case temperature does not exceed + 85°C;

- power supply voltage does not exceed 17 V.

If any of three first mentioned conditions is not met, unit remains in stand-by mode.

The PA is provided with a forced air cooling system and is protected against load mismatch, overheating
and overvoltage. The load mismatch protection smoothly reduces output power as the load VSWR
increases above 2:1.

Three LED on the front panel indicate the unit status. The green LED “TX” shows that the output power
is between the nominal (>30 W) and minimum set power ( ~20 W). The red LED “G/F” (general fault)
turns on during overheating or overvoltage. The red LED “VSWR” is active when the load VSWR is
above 2:1.

The PA has three outputs (open collector) for remote status monitoring. In an alarm state, the level is
pulled low.

The block diagram of PA is represented in Fig. 1.

2. General parameters.

- Frequency range, MHz . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 450 - 512;

- Output power, W;

o nominal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . > 30;

o minimum set by local or remote control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . < 20;

o in stand-by mode operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . < 0.2;

- Harmonic level at the output, dBc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . < -70;

- Reverse intermodulation attenuation, dB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . > 40;

- Input power, W:

o nominal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.0;

o maximum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.0;

o guaranteeing the stand-by mode operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . < 0.5;

- Input VSWR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . < 1.8;

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- Carrier attack time, ms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . < 5.0;

- Remote control voltage, V:

o working range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 – 9.5;

o guaranteeing the nominal output power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . > 7.0;

o guaranteeing the stand-by mode operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . < 1.0;

- Enhancer:

o nominal passband gain. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.7 dB;

o nominal bandwidth. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 450-512 MHz;

o rated mean output power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 W;

o input and output impedances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50 ohms;

The Manufacturer's rated output power of this equipment is for single carrier operation. For situations
when multiple carrier signals are present, the rating would have to be reduced by 3.5 dB, especially
where the output signal is re-radiated and can cause interference to adjacent band users. This power
reduction is to be by means of input power or gain reduction and not by an attenuator at the output of the
device.

3. Construction.

Unit is realized as a module – see Fig. 2.

There are at the front panel:

- RF connectors;

- Fan, which pushes the air across an internal heatsink;

- Status LED;

- Access hole to the power set potentiometer;

- Handle for moving the unit into/from a subrack;

- Four quick release fasteners for fastening the unit in a subrack.

Front panel dimensions are 5.585”(W) x 5.055”(H). The full length of PA does not exceed 8.2”.

The PA contains two PCB assemblies: the Main Board Assembly and the DC Connector Board
Assembly.

The Main Board is placed inside a shielded compartment and is to the main chassis plate/heat spreader.
The heatsink is attached to the outer side of Main Plate, as well as the fan controlling thermal switch.

The Main Board contains RF circuitries and the majority of DC circuits. The DC Connector Board
includes the LED, power controlling potentiometer, a fan voltage regulator and three DC connectors.
The control, monitoring and supply lines between the Main Board Assembly and the DC Connector
Board Assembly are routed through feedthrough filters, screwed into the Main Plate and are connected
through an 8-wire cable and two pairs of connectors (6-pin and 3-pin on the cable end, and 6-pin and 4­pin in the DC Connector Board). This allows the same cable to handle the two modes of operation
(remote or local, depending on which pins are connected.

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