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Bi-Directional beverage antenna 2 coax outputs manual

Bi-Directional beverage antenna 2 coax outputs manual

With careful attention to design and construction, a single beverage antenna can be made to cover two directions with good performance. The transformer at the end of the beverage is designed to match impedance of the antenna. Compare to single wire beverage antenna, where there is only load resistor, in this system all transformers must be calculated exactly for the antenna design (height, wires space and diameter etc).

Principle

This version is designed for antenna direction sharing into the more RX. Together with our gears you can run SO2R or MM and share antenna outputs to more TRX. There are two output connectors with both directions from antenna at the same time.

Construction

Beverage antennas should be installed more than a wavelength from other large metallic structures, such as vertical antennas, towers, power lines, electric fence wires etc. Antenna units can be mounted on trees, wooden pole or fiberglass rods - DO NOT use metal pipes and never mount this unit with the connectors facing up.

The parallel wire line used to construct the antenna must be perfect balanced transmission line conditions. The wires must be parallel to the ground. A line should not be constructed in a vertical fashion, using single support poles with one wire under the other. The closer the wire spacing of the line, the lower the impedance of the line, and the less critical installation-related unbalances become. When the antenna is ladder-line (300 or 450 Ohm) - twist the ladder line multiple times along its length.

Feeder Box

This box contains transformers, direction relay, common-mode filter and protections.

2 coax version with PL SO-239 connector

2 coax version with F connector

Schematic

schematic bi-dir beverage 2 coax qro.cz hamparts.shop

Part list

NAME	PART	VALUE
VP 1-2	neon lamp	lamp 65V
PTC1	PTC	PTC 100mA
VAR1	varistor	14V DC
Tr1, Tr2	transformer	BN-6802-73

PCB

pcb bi-dir beverage 2 coax qro.cz hamparts.shop

Terminator Box

This box contains of Load transformer and protection.

Part list

NAME	PART	VALUE
PTC	PTC	PTC 100mA
Transformer	transformer	BN6802-73

Schematic

schematic terminator bi-dir 1 coax qro.cz hamparts.shop

PCB

pcb terminator bi-dir 1 coax qro.cz hamparts.shop

KIT

2 coax version with PL SO-239 connector

2 coax version with F connector

Transformer winding

Transformers winding - ⚠ very important thing!

This is very important part of the Bi-Dir antenna. All three transformers are calculated directly for antenna construction (wire diameters, space, height...). We recommend to read more of the theory in ON4UN's LBDX or google.

ℹ Use our simply TRANSFORMER CALCULATION FILE.

example of transformer winding

CMCC construction

- common-mode current choke construction
- wind 4 turns on one side then cross to another side of the cores and wind rest turns.

cmcc construction qro.cz hamparts.shop

Article

ℹ Read article by Greg Smith, ZL3IX and article CLASSIC vs BOG beverage antenna.

FAQ

Grounding

GND screw on feeder box is insulated from Coax shield. This isolation prevents introducing unwanted signals and noise into the antenna system. Grounds are insulated by Common-Mode filter.
Connect the ground terminal screws only to earth ground using at least one (copper/army GND rods with screw) ground rod. Use as large diameter ground rod as possible.
A good ground system improves performance (lower noise) and enhances lightning survivability.

Antenna construction

The parallel wire line used to construct the antenna must be perfect balanced transmission line conditions.
The wires must be parallel to the ground. A line should not be constructed in a vertical fashion, using single support poles with one wire under the other. The closer the wire spacing of the line, the lower the impedance of the line, and the less critical installation-related unbalances become.
When the antenna is ladder-line (300 or 450 Ohm) - twist the ladder line multiple times along its length.
With advantage you can use wire antenna insulator pack which you can find at our web category PARTS & ACCESSORIES.

Switching the direction

One coax version has got internal relay for direction switching. Without voltage on coax, the antenna works in REVERSE direction.
You have to apply +12V (or AC) to switch direction to STRAIGHT.
Please use Bias-Tee or controller which is designed for low bands. Do not use cheap bias-tee boards from China which are usually designed for higher bands (VHF).

Construction parameters

Compared to a classic single wire beverage, these Bi-Dir parts are designed exactly for the right type of mechanical/electric construction. For example you can not use 2 wire (10-20cm spaced) boxes for WD-1 wire.
The same for construction of BOG and antenna in the air. Parameters = Transformers are calculated directly for the design.
Beverage antennas should be installed more than a wavelength from other large metallic structures, such as vertical antennas, towers, power lines, electric fence wires etc.
Antenna units can be mounted on trees, wooden pole or fiberglass rods. Do not use metal pipes. Never mount this unit with the connectors facing up.

First antenna testing

When the antenna is mounted on place, you can measure SWR. With VNA or antenna analyser. SWR must be lower than 1:2 for 75 Ohm output and 1:1.7 for 50 Ohm version.
You have to connect dummy load (50 or 75 ohm) to the second port when you measure SWR on TWO coax version.

Check your antenna time to time

Due to storms, lightning and animals we recommend to check SWR of the antenna time to time. If there is any problem with high SWR, please bring the feeder and terminator boxes close to each other and connect it with three short wires, measure SWR again.

Signal Strength

STRAIGHT DIRECTION: There is little that can go wrong to reduce the level of the wanted forward signal significantly. Attenuation along a lossy line may have a small effect, and a poor ground connection at the feed end may reduce the signal by a dB or two, since the ground loss forms a potential divider with the common mode characteristic impedance.
REVERSE DIRECTION: The level of the reverse direction signal will be affected more by line attenuation than that of the forward direction signal, since the signal has to traverse the line twice. Lines with a significant loss, such as some samples of WD1, may make a noticeable difference. Any loss in the ground connection at the reflection transformer forms a potential divider with the common mode line impedance, and can also contribute to signal loss.

Product details

Included in package

Bi-directional box assembled and tested or all parts for KIT version
Bi-directional terminator assembled and tested or all parts for KIT version

Box dimensions (mm)	100x100x50 mm - PU box IP56
Box dimensions (mm)	65x58x35 mm - PU box IP56
PCB dimensions (mm)	95x40 mm
PCB dimensions (mm)	50x33 mm
Weight brutto (kg)	0.55 to 0.58 kg

Manufacturer:

Ing. Jan Šustr
ID 05476356, VAT CZ8407024780
Palachova 1777/7, 591 01 Žďár nad Sázavou, Czech republic, Europe

General instructions:

Please also read general instructions before handling the product.

European Union Declaration of Conformity

Manufacturer Ing. Jan Šustr (QRO.cz):

ID 05476356, VAT CZ8407024780
Palachova 1777/7, 591 01 Žďár nad Sázavou, Czech republic, Europe

declares that the assembled product:

BI-DIR 2C/BI-DIR BOG 2C

is compatible with the relevant Union harmonisation legislation directives:
EMC Directive 2014/30/EU
ČSN EN 61000-6-3 ed. 2
ČSN EN 61000-6-1 ed. 2 (333432)

On behalf of Ing. Jan Šustr (QRO.cz)
Ing. Jan Šustr, CEO
1st January 2023

The beverages work GREAT!!!!!!

No noise on them, but the best was the “diagram”, in my case, if I selected the NA beverage, it eliminates the signals coming from EU, nice F/B of around 20db but better F/S of at least 25/30db!!!!!! Its normal??????? Both of them are about 250m, in the ground just aluminium pipe of around 1m, no radials, the ground was complety wet and mud.

- Imanol, EC2DX -