Dx engineering Maxi-core dxe-bal450h10-bp Instruction manual

Maxi-Core®

Special Line Transformers

DXE-BAL450H10-BP

DXE-BAL450H10-BP-INS Rev 0b

P.O. Box 1491 ∙ Akron, OH 44309-1491 USA

Phone: (800) 777-0703 ∙ Tech Support and International: (330) 572-3200

Fax: (330) 572-3279 ∙ E-mail: [email protected]

Introduction

The DX Engineering Maxi-Core®Special Line Transformers are designed to be used in the

construction of an ultra-low loss, low cost, long length feedline system for 50 ΩHF antennas.

The model DXE-BAL450H10-BP consists of a pair of DXE-BAL450-H10-B high power 450 Ω

balanced to 50 Ωunbalanced line transformers which may be used at each end of any length of 450

Ωparallel wire transmission line. This allows a cost-effective, low-loss, very long feedline to be

created, to connect a 50 ΩHF transmitter or transceiver to a distant matched 50 ΩHF antenna

system.

Using Maxi-Core®Technology, the DXE-BAL450-H10-B Special Line Transformer is a heavy

duty 450 Ωto 50 Ωcurrent choke balun that operates from 1.8 MHz to 30 MHz. Maxi-Core®

Technology contributes significantly higher common mode impedance and a larger effective core

area than similar designs made with conventional enameled wire or bead baluns. This results in:

Higher power handling with lower loss –more power to the antenna

Widest bandwidth –covers all amateur HF frequencies

Reduced RFI –less interference to and from your radio

Additional construction benefits include:

Internal DC shield ground and arc gaps improve lightning protection and reduce static

Teflon®silver coax connector, ceramic output posts, stainless steel terminals, and rugged

aluminum housing provide maintenance-free operation

Specifications

DXE-BAL450H10-BP Maxi-Core®high power matching transformers include internal current

chokes. They provide exceptional common mode current isolation between their 450 Ωbalanced

line terminals and their unbalanced 50 Ωcoaxial cable connections over a wide frequency range.

High common mode isolation from an internal choke, along with the carefully balanced matching

transformer, significantly reduces stray signal reception and feedline radiation when compared to

other less sophisticated matching methods.

1.8 MHz through 30 MHz

5 kW Continuous

10 kW Intermittent

Formed aluminum case

Top quality Teflon®SO-239 connector to connect the user supplied coaxial cable

Ceramic insulators with stainless steel connection hardware for connecting to 450 Ωladder

line

Please Note: The designation "450 Ω" is conventional terminology in Amateur Radio, even though the

specifications for 450 Ωladder line can range from 380 Ωto 430 Ω. The Maxi-Core®Special

Line Transformers were designed specifically for this application.

General Information

Some operators have access to moderately distant areas of land that may be ideal locations for many

types of low SWR 50 ΩHF antenna installations. However, the distance between the station and the

desired antenna system is too long, due to high cable losses, for the use of standard RG-8 or RG-

213 type coaxial cables. Furthermore, the use of expensive, ultra low-loss helical and hardline

coaxial cables can be very cost prohibitive.

The DXE-LL450-5C (500 foot spool) or DXE-LL450-1K (1,000 foot spool) 450 Ω

ladder line, available from DX Engineering, also known as “window” type of parallel-

wire transmission line, is readily available at a fraction of the cost of standard coaxial and

larger flexible or hardline cables.

Specifically, balanced 450 Ωladder line offers the major advantage extremely low RF loss as

compared to standard coaxial cable, and can be properly installed over long distances much more

easily than other feedlines.

The use of home-made or commercial open-wire feeder with "spreaders" is discouraged. Parallel

open-wire impedance is difficult to maintain with the correct conductor separation over long lengths

and the conductors are prone to shorting if installed with the proper axial twist. 450 Ωladder line is

constructed to assure constant spacing of the conductors and constant impedance over its length.

The RF power loss of 450 Ωladder line is lower than the loss of all 50 Ωand 75 Ωcommercial

hardline and CATV hardline cables 7/8" and smaller, and is equal to the loss of 1-1/4" hardline!

(Loss figures from The ARRL Antenna Book)

The loss of 450 Ωladder line is typically 1/10 of the loss of RG-213. Depending upon feedline

length and frequency of operation, power transfer and signal reception can be improved by 2 to 5

dB using DXE-BAL450H10-BP Special Line Transformers and DXE-LL450-5C or DXE-LL450-

1K 450 Ωladder line that represents an improvement of one and a half to over three times in system

performance when transmitting.

Table 1 shows the Cable Loss at 10 MHz in dB and approximate cost1of each 50 Ωfeedline system

is shown, compared to DXE-BAL450H10-BP Special Line Transformers and DXE-LL450-5C or

DXE-LL450-1K 450 Ωladder line.

Line

RG-213

Belden 8267

Low-loss

LMR-400DB

1/2” Heliax®

LDF4-50A

7/8” Heliax®

LDF5-50A

450 ΩLadder Line

(with DXE Special Line

Transformers 2)

Line

$/foot

$1.40/ft

$1.05/ft

$2.60/ft

$6.30

$0.49 or less

Feet

$US

dB3

$US

300

2.4

420.00

1.2

315.00

0.6

780.00

0.3

1890.00

0.6

446.95

500

3.0

700.00

2.0

525.00

1.0

1300.00

0.5

3150.00

0.7

544.95

1000

6.0

1400.00

4.0

1050.00

3.0

2600.00

1.0

6300.00

1.0

749.94

1. Approximate costs of these feedline systems are for the feedlines only and do not include connectors, trenching, feedline supports, or

installation labor costs. Costs were estimated in August of 2009.

2. This approximate $US cost includes the 450 Ωladder line and two DXE-BAL450-H10-B Special Line Transformers

3. Nominal insertion losses of 0.2 dB per Line Transformer is included

Table 1

The installation of long runs of low-loss coaxial transmission lines requires that a "Do-It-Your

Selfer" rent a trencher. Otherwise, the digging of the very long trench must be contracted with an

excavation company, which can cost many hundreds and even thousands of additional dollars.

Digging a trench for transmission lines is not feasible in steep or rocky land areas, and rigging such

heavy cable at appropriate heights above the reach of animals would also be cost prohibitive.

Installation of a very long above-ground 450 Ωultra low-loss feedline can be done at a reasonable

cost by almost anyone. Using posts made of treated lumber, fiberglass, or by attaching the ladder

line insulators to available trees, this type of long feedline system opens up new possibilities for

those who own or have access to land, even in steep grade areas. Even if one were to contract the

installation of this type of feedline supports with a fence company, using three to five posts per

hundred feet and no fence material, the overall cost of a 450 Ωfeedline system is much lower than

equivalent low-loss coaxial transmission lines. Maintenance of 450 Ωladder line is relatively

inexpensive. In the case of damage from a major weather event, or due to a dozen or more years of

exposure in a harsh environment, the repair or replacement cost of a new run of 450 Ωladder line is

well within any budget.

The 450 Ωfeedline must be supported above ground by at least one foot and must not be covered

with accumulated or drifting snow. It is recommended that the 450 Ωladder line is installed above

the reach of animals and riders, at about 8 to 12 feet above ground. Any influence from other wires

or the ground is easily minimized by maintaining feedline separation of a few to several inches and

by twisting the ladder line axially several turns per span. This also helps prevent wire fatigue, and

reduces the amount of rain, snow and ice collecting on the feedline, which can have an effect on the

impedance and loss of the system. According to the ARRL Handbook for Radio Communications,

the 450 Ωfeedline may be treated with some types of wax based products to minimize rain water

collection and to speed the drying of accumulated rain or dew.

Figure 1 - Typical 450 ΩLadder Line - Any length - Twisted

Figure 2 - Use of DXE-LL-INS Ladder Line Supports

This long length feedline system may be used with low SWR or matched 50 Ωantennas. Un-

matched systems such as random length horizontal or vertical antennas should not be used, since

any line transformer system would transform the wide variety of impedances across a wide

frequency range to values beyond the reach of antenna tuners. However, matched, 50 Ωmulti-band

antennas may be used. Only low SWR, 50 Ωantennas may be successfully fed at low loss using this

50 Ωunbalanced to 450 Ωbalanced to 50 Ωunbalanced transmission line system.

Both balanced terminals are effectively floating,or ground independent,over the operating

frequency of the special line transformers.

Connections

When making 450 Ωladder line connections to the balanced terminals, it is recommended that you

install ring terminals on the ladder line rather than just twisting the bare wire around the terminals.

Using ring terminals will provide a longer lasting reliable connection.

Additionally, the use of a 3/8" open-end wrench is strongly suggested to hold the hex nut in place

while you hand tighten the wing nut. This will prevent the 2-1/2" long hex bolt that goes inside the

balun from rotating and possibly breaking an internal soldered connection.

The supplied wing nuts should be hand tightened only. Do not use pliers or other tools to tighten

them as excessive force may damage the internal connections or the ceramic insulators.

Figure 3

Connection of Ladder Line

and Hand Tightening the Wing Nuts

Installation

While the installation of this special line transformer is a simple process, there are a multitude of

factors to consider when designing and erecting antenna systems. The antenna mounting height,

proximity to structures, the feedline type, length and velocity factor are all factors that affect

antenna performance.

Mounting

The DXE-BAL450-H10-B Special Line Transformers are manufactured with a formed aluminum

enclosure. Although mounting is application specific, follow these general guidelines:

The DXE-BAL450-H10-B Special Line Transformers are not affected by moisture and may be left

outside in all types of weather, including heavy rain, as long as the balun is positioned so that water

will drain from the case. However, they may not be immersed in water and care should be taken to

avoid blocking the drainage of any water that could get inside.

For most installations, weather-sealing of the formed aluminum enclosure balun is not required. If

you chose to add weather-sealing to enhance weather resistance, it may be useful to put a bead of

high quality, non corrosive, marine grade silicone UMI-82180,along the top facing seam where the

two halves of the case meet. Depending on the mounting orientation, leave a small opening in the

seam at the lowest point to allow any condensation to drain. Silicone sealant which contains acetic

acid, which has a vinegar-like smell, is corrosive to aluminum and should be avoided.

A high quality DXE-PL259 Teflon®silver PL-259 connector on your coaxial cable is

recommended. Be sure to weather-seal the coaxial connection with proper tape layers. Use DXE-

3M2155 rubber splicing tape and wrap the connector with one layer from end-to-end while

stretching the tape by a factor of about 2:1. Follow with a wrap of TRM-06132 vinyl tape. Unlike

some waterproofing solutions promoted to the Amateur market, the DXE-3M2155 splicing tape can

be easily removed at any time and will not permanently adhere to the fitting.

The DX Engineering DXE-BAL450-H10-B Special Line Transformers require no maintenance

when properly installed.

Optional Items

DXE-LL450-1K - Ladder Line, 450 Ω- 1000 ft. Spool - DXE-LL450-1K

DXE-LL450-5C - Ladder Line, 450 Ω- 500 ft. Spool - DXE-LL450-5C

Transmit-quality 450 Ωladder line for your antenna project when the feedpoint impedance is close to 400 ohms. It is also ideally

suited for use with our Reversible Beverage Antenna, the RBS-1P. This quality line is constructed of 16 gauge conductors that

are formed by 19 strands of 29 gauge copper-clad steel wire which provides the strength to hold up for long runs between supports.

Actual impedance is nominally 400 ohms with a nominal velocity factor of 91%.

1000' or 500' Spools

Conductor AWG (strand): 16 (19/29)

Nominal Impedance: 400 Ω

Velocity factor of 91%

DXE-LL-INS - 450 ΩLadder Line Supports (25 per pack)

Top grade, UV stabilized, polyethylene ladder line supports designed for Beverage antennas that use 450 Ωline as the antenna wire,

like the DXE-RBSA-1P.

25 Per Pack

Easy to install

Molded Pin Holds Wire or Ladder Line Tightly –Simply pull the pin to release.

Fits Standard Wood Posts

Heavy Duty Flange Holds insulator to Post

Top Grade, UV Stabilized Polyethylene Prevents Arcing and Provides Long Life

5 Year Warranty

Balun, FCC & VFCC Mounting Kits Use one of these BMB kits to mount your DX Engineering Balun to the

bottom of a vertical, the boom of a Yagi, antenna mast or a tower leg. Three different kits fit tubing or pipes from

3/4 in. to 3 in. The Dipole Adapter Bracket kit can be used as the center insulator of a dipole and allow a balun to be

mounted right at the feedpoint. These kits will work with any DX Engineering balun.

DXE-BMB-1P

Balun Mounting Kit for a .750 in. thru 1.50 in. Boom

DXE-BMB-2P

Balun Mounting Kit for a 1.56 in. thru 2.25 in. Boom

DXE-BMB-3P

Balun Mounting Kit for a 2.31 in. thru 3.00 in. Boom

DXE-9551 - Replacement Ceramic Insulators

2 ceramic insulators for use with DX Engineering Baluns.

DX Engineering Baluns utilize 4 Ceramic Insulators per balun, however our replacement insulators are sold in pairs.

DXE-VFCC-BRKT - Balun or Feedline Current Choke Mounting Kit for HF Verticals -

This mounting kit allows you to mount a DX Engineering Balun or Feed Line Current Choke at the base of any

vertical antenna. The polymer mounting plate is isolated from the rest of the vertical ground system for best

performance and decoupling. The mounting bracket was designed to utilize one DX Engineering V-bolt Saddle

Clamp DXE-CAVS-1P, to mount the bracket to a 1/2”to 1-3/4”ground pipe. Also available are the heavy duty

DXE-CAVS-11P for 1/2”to 1-3/4”pipe and DXE-SSVC-2P for 1 to 2 in. pipe. The V-Bolt Saddle Clamps are not

included and will need to be purchased separately if you choose to mount your bracket to a ground pipe. If, you are

mounting to a 4”x 4”or 6”x 6”wooden post then no clamps are necessary; simply use (2) wood screws.

Works with any DX Engineering Formed Aluminum Enclosure

Kit includes:

Polymer mounting plate and aluminum adaptor bracket

Stainless steel mounting hardware

DXE-3M2155 - 3M Temflex™ 2155 Rubber Splicing Tape

Conformable self-fusing rubber electrical insulating tape. It is designed for low voltage electrical insulating and moisture

sealing applications. For outdoor use, it should be protected from UV deterioration with an overwrap of TRM-06133

TRM-06133 - Scotch® Super 33+.

Highly conformable super stretchy tape for all weather applications. This tape provides flexibility and easy handling for

all around performance. It also combines PVC backing with excellent electrical insulating properties to provide primary

electrical insulation for splices up to 600V and protective jacketing. Both tape products are available from DX

Engineering.

UMI-82180 - DX Engineering Approved RTV Sealant By Permatex®

We have all used RTV to seal water out of things, right? Have you ever sealed a piece of electronic gear with it --

then opened it some time later to find that it had still managed to become corroded inside? Guess what? It's not the

rain that corroded it - It's the RTV! Normal RTV gives off acetic acid when it cures. That's the vinegar smell. The

acetic acid causes the corrosion. DX Engineering has located a Neutral Cure RTV made right here in Ohio that is

non-corrosive and is safe for sealing those baluns and other electronic gear that are going to be out in the weather.

Applies just like "normal" RTV, dries in one hour and cures in 24 hours at 70 degrees F.

And it doesn't smell like vinegar!

3.3 oz. Tube

Black *This part is classified hazardous and is limited to domestic UPS Ground shipping only

Technical Support

If you have questions about this product, or if you experience difficulties during the installation,

contact DX Engineering at (330) 572-3200. You can also e-mail us at:

DXEnginee[email protected]

For best service, please take a few minutes to review this manual before you call.

Warranty

All products manufactured by DX Engineering are warranted to be free from defects in material and workmanship for a period of one (1) year from

date of shipment. DX Engineering’s sole obligation under these warranties shall be to issue credit, repair or replace any item or part thereof which is

proved to be other than as warranted; no allowance shall be made for any labor charges of Buyer for replacement of parts, adjustment or repairs, or

any other work, unless such charges are authorized in advance by DX Engineering. If DX Engineering’s products are claimed to be defective in

material or workmanship, DX Engineering shall, upon prompt notice thereof, issue shipping instructions for return to DX Engineering (transportation-

charges prepaid by Buyer). Every such claim for breach of these warranties shall be deemed to be waived by Buyer unless made in writing. The above

warranties shall not extend to any products or parts thereof which have been subjected to any misuse or neglect, damaged by accident, rendered

defective by reason of improper installation, damaged from severe weather including floods, or abnormal environmental conditions such as prolonged

exposure to corrosives or power surges, or by the performance of repairs or alterations outside of our plant, and shall not apply to any goods or parts

thereof furnished by Buyer or acquired from others at Buyer’s specifications. In addition, DX Engineering’s warranties do not extend to other

equipment and parts manufactured by others except to the extent of the original manufacturer’s warranty to DX Engineering. The obligations under

the foregoing warranties are limited to the precise terms thereof. These warranties provide exclusive remedies, expressly in lieu of all other remedies