Mirage BD-35 Instructions manual

MIRAGE BD-35 Dual Band Amplifier

MIRAGE BD-35

DUAL BAND POWER AMPLIFIER

INTRODUCTION:

The Mirage BD-35 is a 45/35 watt dual band power amplifier for use with
today's dual band handie talkies operating in the 144/440MHz bands. We
have succeeded in the development of a c ross-band full duplex f unction and
have incorporated it into this design. The compact design of the power
amplifier unit employs the new "two band / one RF power transistor"
technique. The BD-35 is a
for the

FEATURES:

discriminating

•

High output power

Up to 45 watts at 144MHz or up to 35 watts at 440MHz. 30 to 35

watts is achieved with 2 to 6 watts input.

•

Input power from 0.3 to 7 watts

With an input power of 7 watts m aximum, the Mirage is compatible

with most modern hand-held tranceivers.

•

Small size

This amplif ier's s ize mak es it the per fec t com panion f or f ield operation

without the added weight.

•

Automatic Frequency selection and control circuit

This allows the amplifier to have only one input connector and makes

for a perfect match for today's dual band radios and dual band
antennas.

•

Reverse DC power polarity protection circuit

Protects the amplifier from accidental reversing of the power leads.

•

"ON-AIR" indicator

Lets you know that you are transmitting.

remarkable

Amateur Radio operator.

and

useful

dual band power amplifier

1

SPECIFICATIONS:

FREQUENCY: 144 TO 148MHz / 430 TO 450MHz
RF INPUT: 0.3 - 7 watts
RF OUTPUT: Up to 35 watts at 440MHz and up to

DUTY CYCLE: INTERMITTENT (ICAS)
MODES: F3 (FM)
KEYING: AUTOMATIC SENSING
SUPPLY VOLTAGE: 12 -15 Vdc
RF CONNECTORS: TWO (2) SO-239 UHF
SUPPLY CURRENT; 7 AMPS TYPICAL
FUSE: 8 AMP, FAST BLOW
INPUT/OUTPUT IMPEDANCE: 50 OHMS

EXPLANATION OF FEATURES:

••••

VHF ON AIR LAMP

This LED indicates that the power amplifier is transmitting in the VHF
(144 - 148MHz) band.

••••

UHF ON AIR LAMP

This LED indicates that the power amplifier is transmitting in the UHF
(430 - 450MHz) band.

••••

POWER ON LAMP

When the power switch is engaged the amplifier will illuminate the

POWER ON

amplify any signal of the proper frequency applied to its input.

••••

ANT (RF OUTPUT)

The coax from your antenna is connected to this port.

••••

RADIO (RF INPUT)

The coax from your radio or exciter is connected to this port.

••••

DC PWR (13.8V)

This port has two wires. The
FUSE holder. The
amplifier will accept from 12 to 15 Vdc.

lamp. This lets you know that the amplifier is ready to

Red

Black

wire is for negative. The Mirage BD-35

MIRAGE BD-35 Dual Band Amplifier

45 watts at 144MHz

wire is for positive and incorporates a

2

MIRAGE BD-35 Dual Band Amplifier

INSTALLATION AND OPERATION:

The Mirage BD-35 may be mounted using the bracket supplied or simply
placed in a convenient operating position. In either case, there must be
adequate ventilation for the finned heat sink . This generally means at leas t 1
inch clearance from the heat-sink to any surrounding enclosure and an
unobstructed flow from the front to the back of the heat s ink. Do not operate
the amplifier in places where it will be expos ed to direct sunlight or a nearby
heat source such as heaters, radiator, etc.

+

CAUTION: With extended use, the heat sink becomes VERY HOT!

If it is necessary to extend the DC power leads, use wire of the s ame gauge
in order to avoid a voltage drop on your power leads. Be careful that the DC
power supplied is no higher than 15 Volts or dam age may result. A source
voltage of 13.8 Vdc is recommended and should be used whenever available.
Some automobiles will generate a high current surge when started. It is
recommended that the am plifier be placed in the

OFF

position when starting

your vehicle.
Use a minim um length of good quality 50 Ohm cable between the radio and

the amplifier. The antenna s ystem should have a VSW R of 1.5 : 1 or better
for best perfor mance. If used in a m obile installation, choose a good m obile
antenna which will withstand the power of this amplifier. Be sur e to c hec k the
SWR f or any degrading once the antenna has been heated by a few minutes
of operation. An antenna with a rating of 100 watts is recommended.

Never connect the "rubber duck" antenna supplied with your tranceiver
directly to the antenna connector of the amplifier unit by use of a SO-239 to
BNC converting unit, or by any other means; It may cause damage to both
the amplifier and the "rubber duck."

When utilizing a mono band antenna, check the transmitting frequency of
your radio and be sure that it is matched to the type of antenna you are using
prior to operation. Furthermor e, when inserting coaxial switches to either or
both input or output of the power amplifier in order to operate two sets of
tranceivers and antennas of which the frequenc ies differ, be s ure to carefully
check switch positions.

3

MIRAGE BD-35 Dual Band Amplifier

A typical connection of this amplifier with duplex type dual band tranceiver
and a dual band antenna is shown in
is made with either two tranceivers or two antennas, please refer to

2

or 3.

Figure 1

. If connection of this am plif ier

Figures

4

MIRAGE BD-35 Dual Band Amplifier

During 145MHz / 435MHz crossband full duplex operation, there may be
some m inor interferences such as noise on certain fr equencies (depending
on the combination of Transmit / Receive frequencies selected). Select
TX/RX frequencies which show no interferences and/or trouble especially
with a 145MHz band transmission and a 435MHz reception. Select
frequencies that are not mutually harmonic.

With som e regulated DC power supplies, the output voltage may rise to an
abnormal level, resulting from malfunctions due to RF signal intrusion.
Therefore, use a power supply with sufficient cur rent capacity as well as with
good protection against RF intrusion. If the power supply malfunctions,
discontinue operation by turning the power switch off.

If the amplifiers power cables are connected in reverse polarity, the cables
could sustain damage, espec ially when your source is a battery. Be sure to
check the polarity before connection!

After confirmation of proper connections, etc., turn the power switch ON.
Transmit either a 146MHz or a 440MHz signal to the antenna and confirm the
SWR and that the proper LED is illuminated for the band of operation. Switch
the band of operation to the opposite and of the one selected above and
transmit again to confirm that the amplifier has detected the proper band
(once again, by the illuminated LED) and SWR.

TROUBLESHOOTING:

The Mirage BD-35 is designed for long, trouble-free perf ormance and should
not require extensive troubleshooting in the field. If difficulty is encountered,
check the following before assuming the amplifier has a malfunction:

1. Loose antenna or power supply connections

2. VSWR of the antenna system

3. Coaxial cables from radio to amplifier, and amplifier to antenna

4. Output voltage of power supply

5. Power output of radio

6. Improper fuse rating

5

MIRAGE BD-35 Dual Band Amplifier

TECHNICAL ASSISTANCE:

If you have any problem with this unit, f irst check the appropriate section of
this manual. If the m anual does not reference your problem or your problem
is not solved by reading the manual you may call

MIRAGE

601-323-8287

at
You will be best helped if you have your unit, manual and all information on
your station handy so you can answer any questions the technicians may ask.

You can also send questions by FAX to

601-323-6551

. Send a complete
description of your problem, an explanation of exactly how you are using your
unit, and a complete description of your station.

.

6