Crescend P2-RTK-450
Power Amplifier User Manual
1. General Information
The P2-RTK-450 is a AB class power amplifier (PA), intended to work with UHF RTK positioning syst ems,
amplifying phase modulated signals.
PA has the automatic gain control (AGC) l oop. The gain value is set up in the factory.
PA is protected against the load mismatch and ov erheating. It is also protected against exces sive DC power
supply voltage and DC voltage reversed polarity (for short time). PA has a current limiter, which threshold goes
down in the case of overheating.
PA provides LED indication of normal and alarm modes, as well as the combined alarm signal.
PA contains an externally controlled by-pass line, activated either when the power supply voltage is removed, or
when the special pin “SH/D” is pulled to the ground.
There is a forced air cooling system, working when the unit is in the amplifying mode.
The general parameters of RTK-450 in the normal operation mode are listed below:
Frequency range of operation (f), MHz . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 450 - 470;
Input power (Pin), W . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.4 – 2.0;
Input return loss, dB, not less than . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10;
Gain in the normal operation (G), dB, nominal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11;
Bypass insertion loss, dB, not greater than . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.0;
DC power supply voltage (Vsup), V
- nominal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.8;
- working range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.0 – 17.0;
DC current (Io), A, not greater than
- in amplifying mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.5;
- in quiescent mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.8;
- in by-pass mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.002;
Working ambient temperature range, ºC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -30 to +60;
Threshold of overheat protection activation: heat sink temperature, ºC . . . . . .. + (85 + 5);
RF connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 Ohm, N (F);
DC connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . screws # 6-32 AWG.
2. Construction
The unit is intended for installation in a standard 19” cabinet rack, where it takes 4U (7.0”) in the vertical
direction. Its depth does not exceed 5”.
There are four LED at the front panel that indicat e the status of unit operation.
There are two N connectors, DC block, four pins (f i l ters) and two ground poles at the rear of chassis. A l so, the fan
is placed over the heatsink at the rear.
2
3. Installation
Unit installation shall provide proper air access to the unit; no obstacle for air is allowed closer than 3” from fan.
Unit shall be protected against the direct solar li ght and precipitation. The air inlets and outlet s sh oul d be checked
every 30 days and cleaned if necessary. If the equipment is operated in a severe dust environment, i t should be
checked and cleaned more often. If dust and dirt are allowed to accumulate, the cooling efficiency will be
diminished. Using either compressed air or a brush with soft bristles, loosen and remove accu m ul ated dust and
dirt from the air inlet panels.
Check that the fans are running smoothly. A slow ru nni ng or noisy fan may indicate an imminent fan f ai l ure. Heat
is one of the biggest factors in reducing the reliabi li ty of the amplifier. Ensure the fan has access to cool and
clean airflow within the rack.
Copper wires # 12 AWG shall be use in DC power lin e. Wires shall be crimped to ring terminals.
Pre-tinning of crimps is recommended.
Use # 18 or # 20 AWG wire for unit status monitori ng circuit. Connect this wire to the pin “AL A RM ”.
Use # 18 or # 20 AWG wire for forced switching to by-pass mode ci rcuit. Con nect this wire to the pin “SH/D”.
Make sure all connections are constructed and implemented properly with best practices.
Make sure that DC power supply voltage and RF sou rce f requency and power are in the
mentioned above limits and that the DC polarity is correct before applying DC power to the amplifier.
Notes: - The reversed DC polarity protection circuit may not operate longer than 0.3 sec;
- Input power shall not exceed 3 W in the working frequency rang e and shall not exceed
0.3 W out of the specified frequency range of operation.
4. Operation
Green LED “DC ON” is on and fan is running when DC power supply voltage i s appli ed to the unit, its value
does not exceed 17 V and pin “Sh/D” is not connect ed to the ground.
Red LED “LOW OUTPUT” is on if gain is less than 6 dB or input power is less than 0.1 W.
Red LED “HIGH VSWR” is on when the load VSWR ex ceeds 2:1.
Red LED “HIGH TEMP” is on when the heat sink temperature reache s +(85 + 5)ºC.
The voltage at filter “ALARM” is about 0.5 V less than power supply voltage during normal operation a nd
drops to 0.3V or less when any of mentioned above red LEDs turn on. If a 2 kOhm resistor is connected
between this filter and the ground, a TTL compati ble output is created.
When switching the PA to the by-pass mode, the resistance between pin “SH/D” and ground shall be less
than 100 Ohm, or, if a transistor key is used, the voltage drop on the key shall not exceed 0.2 V . The
current, coming out from pin “SH/D” does not exceed 1.7 mA.
5. FCC RF Exposure Requirements
CAUTION: This transmitter must be rest rict ed to work related operations in a Controlled RF exposure
environment. All qualified end-users of this dev i ce must have the knowledge to control their expos ure
conditions and/or duration, and the exposur e conditions and/or duration of their passengers a nd bystanders,
to comply with the General Population / Uncontrolled MPE limit and requirements.
Vehicle – Antenna Installation Instructions
3
The antenna(s) used for this transmitter must be i nstalled to provide a separation distance of at least 0.95m
from all persons, must not be co-located or operating in conjunction with any other antenna or t ransmitter,
and must not exceed an antenna gain of 3 dBi with a minimum cable loss of 1.5 dB.
Population/Uncontrolled Exposure envir onm ent:
· Persons should be allowed no closer than 0.95m per the example above.
Failure to observe these restrictions will result i n exceeding the FCC RF exposure limits.
IC RSS-GEN, Sec 7.1.2 Warning Statement- (Required for Transmitters)
ENGLISH:
Under Industry Canada regulations, this radio tr ansmitter may only operate using an antenna of a type and
maximum (or lesser) gain approved for the tran smi tter by Industry Canada. To reduce potential radio
interference to other users, the antenna type and its gain should be so chosen that the equi valent
isotropically radiated power (e.i.r.p.) i s not more than that necessary for successful communication.
FRENCH:
Conformément à la réglementation d'Industrie Canada, le présent émetteur radio peut fonctionner avec une
antenne d'un type et d'un gain maximal (ou inférieur) approuvé pour l'émetteur par Industrie Canada. Dans
le but de réduire les risques de brouillage radioél ectrique à l'intention des autres utilisateurs, il faut choisir le
type d'antenne et son gain de sorte que la puissance isot rope rayonnée quivalente (p.i.r.e.) ne dépassepas
l'intensité nécessaire à l'établissement d'une communication satisfaisante.
IC RSS-102, Sec 2.6 Warning Statements
ENGLISH:
The applicant is responsible for providing proper i nstructions to the user of the radio device, and any usage
restrictions, including limits of exposure durations. The user manual shall provide inst all ation and operation
instructions, as well as any special usage conditions, to ensure compliance with SAR and/or RF field
strength limits. For instance, compliance di st ance shall be clearly stated in the user manual.
The user manual of devices intended for controlled use shall also include information relating to the
operating characteristics of the device; the operating instructions to ensure compliance with SAR and/or RF
field strength limits; information on the inst al l ation and operation of accessories to ensure compliance with
SAR and/or RF field strength limits; and contact information where the user can obtain Canadian information
on RF exposure and compliance. Other related information may also be included.
FRENCH:
Le demandeur est tenu de fournir des instruct ions appropriées à l'utilisateur de l'appareil de rad i o, et des
restrictions d'utilisation, y compris les limi tes de durée d'exposition. Le mode d'emploi doit fournir installation
et de fonctionnement des instructions, ai nsi que les conditions d'utilisation particulières, pou r assurer la
conformité avec SAR et / ou les limites d'intensité de champ RF. Par exemple, la distance de conf orm ité doit
être clairement indiqué dans le mode d'emploi .
Le manuel d'utilisation de dispositifs dest inés à un usage contrôlé doit également contenir de s informations
sur les caractéristiques de fonctionnement de l 'appareil, les instructions de fonctionnement pour assurer la
conformité avec SAR et / ou les limites d'intensité de champ RF; informations sur l'installation et le
fonctionnement des accessoires pour assurer l e respect SAR et / ou les limites d'intensité de champ RF, et
les informations de contact où l'utilisateu r peut obtenir des informations sur l'expositi on canadienne de
radiofréquences et la conformité. Autres renseignements connexes peuvent également être inclus
Loading...