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Texas BugCatcher 

Quality Built by GLA Systems 

“The SERIOUS HF Mobile Antenna” 

4” and 6” Diameter High “Q” Coils for 3 to 30 Mhz Operation Stainless Steel Mast and Hardware - Aircraft Aluminum Capacity Hats All Parts Have Standard 3/8-24 Threads - Tunes All HF Bands 

“COMPLETE HF MOBILE ANTENNA SYSTEMS” 

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The GLA Systems Texas BugCatcher antenna is constructed of the best materials available. The center support rod is 1.5 inch diameter “Delrin”. All coil end connectors are machined from 1 inch Brass Hexagon bar. The fittings are tapped with 3/8-24 threads to allow connection to mast or whip. The coil wire ends are connected to the brass end fittings with lugs and Stainless Steel bolts. This insures the best possible mechanical and electrical connection between the coil and mast or whip. The coil supports on each end are made of polycarbonate (Lexan). Center coil form supports are used on all coils for added strength. No parts are made of PVC or phenolic, both of which are brittle. The coils are the open wound type to prevent the buildup of moisture, dust and dirt between the coil and coilform. All GLA masts are constructed of 3/4 inch outside diameter stainless steel tubing with stainless steel threaded inserts welded in each end. All masts have 3/8-24 female threads on each end. A Stainless Steel threaded stud is provided for each end to allow connection to most any type mount. The capacity hats are made from aircraft type 2024-T4 aluminum. 

The “Texas BugCatcher” antenna can be assembled to meet almost any mechanical configuration necessary to fit a particular installation. However it is important to remember that the center loaded antenna has the highest theoretical radiation efficiency (as much as 50% higher than a similar base loaded system). With this in mind, we strongly recommend a base mast of 3 to 5 feet and a whip length of 4 to 8 feet.Variations from this range will still give excellent results but should be used only when installation requirements prohibit true center loading. When selecting mast length, consideration should be given to several factors. A mast should be used that will allow the bottom of the coil to be at least 6 inches above the roof of the vehicle. It is also important to keep the coil as far above ground as possible to reduce ground losses. This should be increased to 12 inches if the edge of the roof is close to the coil as would be the case with vans, suburbans and other “sport utility” type vehicles. The important thing to remember is that the Texas BugCatcher can be assembled to fi t YOUR particular vehicle and when properly tuned will give excellent performance on all bands. We have systems being used with great success from as short as 7 feet up to lengths of 15 feet on mobile installations and much longer for fixed use. All GLA Systems coils are built with both top performance and durability as a top priority. It is impossible to cover all possibilities in this limited space but we hope we can give you enough information to help you design your Texas BugCatcher. 

A TYPICAL 

Texas BugCatcher 

Antenna Installation Will Contain the Following parts

WHIP 

1/8 IN OR 3/16 IN DiameterEither can be custom cut to desired length 

CAPACITY HAT 

Optional.. Depends on Coil size, Whip length and desired frequency 

LOADING COIL 

Select according to operating frequency and degree of effi ciency desired 

MAST 

Select mast length to insure bottom of loading coil is at least 6 inches above roof of vehicle. 12 inches above roof if loading coil is within 2 feet of body of vehicle. For top performance mast should be at least 3 feet long 

MATCHING COIL 

HD-80 for 10 - 160 Meters 

MOUNT 

A mount must be used to isolate the antenna from ground. A ball mount or stud type mount  is acceptable but MUST be as strong 

as possible. 

 OPTIONS 

CORONA BALL 

3/4 inch diameter corona balls are available when required for high power operation (over 300 watts) 

EXTENDER MAST

6 inch - 12 inch 

Can be used to raise capacity hat above coil. 

COIL TAPS

Banana Plug Taps

Additional banana jack type coil clips with banana plug type jumpers can be ordered to make coil tapping simpler and quicker. 

QUICK-DISCONNECTS 

Quick-disconnects can be used above or below the coil or at the base of the mast to allow easy removal of the antenna. 

SPECIAL BRACKETS 

Some type of special bracket may be required

Trailer Hitch Bracket

Fold-Over Trailer Hitch Bracket

Van or Suburban Bracket

Tire Carrier Bracket

3-Way Mirror Bracket

Lexan Mast support 

400 and 600 Series Coils

These coils have end caps of 3/8” thick Lexan. Wire supports are 3/8” diameter Lexan rod and coil.

The 400 and 600 series coils are custom designed and hand constructed in our own machine shop in Texas.

As with all GLA Systems coils the inserts in each end of the coil center post are machined from 1” hexagon brass bar.    

These coils are 4-3/8 inches in diameter and 7 inches long. They are wound with 12 Ga. wire at 6 turns per inch. The larger diameter along with the shorter length provides a higher “Q” which improves the overall performance on all bands. 

The # 480 COIL

The #480 coil has 85 microhenrys of inductance and will load on 75 meters with a whip length of 72 inches without the addition of a capacity hat.

 When using a capacity hat MINIMUM whip lengths will be as follows:

20 inch hat----- 36 inch whip

16 inch hat----- 48 inch whip

12 inch hat ---- 59 inch whip

These whip lengths are intended as a reference only. The length of the whip should be kept as long as practical. 

# 440 COIL

The # 440 is 4-3/8 inches in diameter but only 4 inches long. The # 440 coil has the same mechanical and electrical advantages as the # 480 coil. Because of its shorter length it is an excellent choice when 75 meter operation is not desired. The #440 coil has 40 microhenrys of inductance and will allow 40 meter operation with a whip as short as 59 inches  

# 480XL COIL 

The 480 XL coil is the same diameter as the 480 coil but is 11 inches long and has 66 turns of 12 ga wire. The 480XL will tune 75 meters with a whip as short as 3 ft without using a capacity hat. 

The 480XL coil is designed for use on tall vehicles such as 18 wheelers which do not allow the use of long whips and the overall height of the antenna must be kept below a maximum height. 

# 680 COIL 

The #680 HQ Coil is 6-3/8 inches in diameter and 7 inches long. It is wound with 12 Ga. wire at 4 turns per inch.

   Because of its larger diameter, shorter length and wider turn spacing the Q of the coil is higher than the #480 which improves the radiation efficiency. The #680 HQ has a total inductance of approximately 85 microhenrys which will allow 75 meter operation with a whip length of 72 inches without the use of a capacity hat. 

Adding a capacity hat will allow whip lengths as follows: 

20 Inch Hat----- 36 Inch Whip

16 Inch Hat ----- 48 Inch Whip

12 Inch Hat ----- 60 Inch Whip

These whip lengths are intended as a reference only. The length of the whip should be kept as long as practical. 

The “Higher Q” makes this coil the best choice for 40 and 75 meter operation. 

# 640 COIL 

The #640 HQ coil has the same mechanical construction as the #680 but is only 4 inches long . This coil is best suited for 10 through 40 meter operation. The # 640 will require a whip at least 72 inches long for 40 meter operation. As with all coils the whip may be shortened by adding a capacity hat.   

# 6160 COIL 

The #6160 coil is 6 inches in diameter and is wound with 12 Ga. wire at 6 turns per inch. It is 10 inches long and will give excellent performance on 160 meters. 

A 20 inch capacity hat and a whip at least 78 inches long will be required.

 Operation on 75 and 40 meters will be possible but tuning oh the higher bands may be troublesome because of the excessive shorted turns. 

Capacity Hats

 2024-T3 Aluminum 

8 Inch Diameter -- $24.00 12 Inch Diameter - $45.00 16 Inch Diameter- $60.00 20 Inch Diameter - $79.00

Capacity hat Info Click Here

Larger hats available on special order. Please call for quote. 

MOUNTS

HD Stud Mount - $10.00 G-200 (Standard Stud Mount)---- $3.50

G-201 (Mount with SO-239) ------ $4.50

SS-750 “Super Stud Mount” ---- $12.95

 (Super Strong Mount with SO-239) (Mounts in 3/4” Hole) G-260 Cowl Mount ---- $8.50 (Mounts in 5/8 Hole) 

G-221 Mirror Mount $6.50 (Aluminum With 1/2” Hole)

G-271Mirror Mount $6.50 

(Stainless Steel With 1/2” Hole) G-272 Mirror Mount ---------------- $6.50 (Stainless Steel With 3/4” Hole)

Special Brackets

     Insulated Feed Through Supplied With Special Brackets Listed Below Fold-Over Hitch Mount ----------$95.00 

The Fold-Over Hitch Mount can be made to special lengths for Ful-sized Vans and other tall vehicles. (Special Order) Lexan mast Support ------ $4.50 

HEAVY DUTY STUD MOUNT 

The GLA Systems Heavy Duty Mount is a heavy duty stud type mount using a 3/4 inch stainless steel hex top piece and a 3/8-24 N.F. Stainless steel bolt for the stud.   

Nylon washers of 1-1/8 inch diameter are used on the top and bottom of the mounting surface to give a larger load bearing surface. The GLA Heavy Duty Mount is recommended where a strong mount is needed on a flat surface.

COIL TAP KIT 

Our new “Banana Plug” coil taps are special built banana jacks that quickly attach to the coil with no tools. They provide an easy and secure tap and can be quickly moved. They are standard on all Texas BugCatcher loading coils .

The “Banana Plug” Tap Kit contains 5 Banana Plug taps and 2 Jumpers.

Once the tap points are located and the special coil taps are in place the frequency can be changed by simply plugging the jumper on at the proper place. 

The “Banana Plug” taps provide an easier and more secure means of tapping the coil.

COIL TAP PARTS 

Coil Top Ring for Banana Plug -- $10.00 Banana Plug Coil Clip ------ $7.00 (Screw to coil and Tap with Banana Plug)

Banana Plug Jumper-------- $4.00 (Plugs into Banana Coil Clip)

Banana Plug Tap Kit -------- $40.00 (5 Banana Plug Coil clips & 2 Jumpers) 

MASTS

6 inch (.5 foot) ----- $30.00

12 inch (1 foot) ---- $32.00

18 inch (1.5 feet) - $34.00

24 inch (2 feet) ---- $36.00

30 inch (2.5 feet)- -$38.00

36 inch (3 feet) ----$40.00

42 inch (3.5 feet) - $42.00

48 inch (4 feet) ---- $44.00

54 inch (4.5 feet) - $46.00

60 inch (5 feet) ---- $48.00

Mast Studs (2 free w/ mast) ----- $1.00 

Special length mast can be made if needed. For special lengths under 60 inches use price of next longest mast plus $5.00.

 For special lengths over 60 inches the price will be $48.00 plus $2.00 for each additional 6 inches ( or portion thereof) over 60 inches

FOLD OVER HITCH MOUNT

is designed to be bolted directly to a trailer hitch where the hitch ball would normally be . This provides a strong mount for the “Texas BugCatcher” or other large antenna without drilling any holes in the vehicle and does not require any additional support such as guy lines. The FOLD OVER HITCH MOUNT is constructed of 1-1/2 inch square steel tube with a steel plate on the bottom to allow bolting to the trailer hitch. A 1/4  inch thick plate with 1/2 inch hole for mounting the antenna is provided 7 inches up from the bottom. It has a pin that can be quickly pulled which allows the mount to fold away from the vehicle to enable a door or tailgate to be opened.A strong antenna support of 1/4 inch thick “lexan” is provided at the top. The Fold-over Hitch Mount is black powder coated for durability. The FOLD-OVER HITCH MOUNT is the answer for antenna mounting on vehicles such as MINI VANS, FULL SIZE VANS, SUV’S, PICKUPS or on any vehicle on which a trailer hitch can be installed

Tuning the Texas BugCatcher

The Texas BugCatcher is relatively easy to tune and tuning can be accomplished by anyone with a little patience and experience. PLEASE remember the word PATIENCE especially when tuning on 75 meters.

After assembling and mounting the BugCatcher on the vehicle it is suggested that you first tune for maximum receiver noise at the chosen frequency. This is easily done by slowly moving the coil tap from the top to the bottom of the loading coil, touching each turn of the coil momentarily and listening for maximum signal strength (or noise).

When maximum signal strength is found, attach the tap clip to the coil at that point and then key the transmitter and check for lowest SWR or minimum reflected power. Tuning can usually be more easily accomplished using a reflected power meter instead of a SWR meter. With the transmitter keyed, rotate the VFO back and forth to locate the resonant frequency. (frequency with lowest SWR or reflected power) After determining the resonant frequency in this manner you will know if the antenna needs to be longer or shorter. Use more turns to make the antenna longer and fewer turns to make the antenna shorter.

Move the coil tap up or down the loading coil to fine tune to desired frequency. At this point let's remember that word "PATIENCE" because small movements on the loading coil and winding the tap wire around the loading coil in opposite directions can make a big difference in resonant frequency. We suggest small movements on the loading coil and frequent checks for resonant frequency. It is recommended that tuning be accomplished on 20 or 40 meters first. The higher frequency bands are a little easier to tune and working with them first will help you get the feel of the tuning process.

At times some of the higher frequencies may be difficult to tune on some of the coils. This is due to the large amount of inductance in the unused portion of the loading coil. When this happens we suggest breaking the unused portion of the loading coil into 2 or more sections. For example you may tap for 40 meters first, leave the 40 meter tap wire in place and then tap from that point on up to the higher frequency. This seems to occur most often on the coils with larger amounts of inductance such as the #88 but can also occur on the other 80 meter coils.

You may find the lowest possible SWR (especially on 75 or 40 meters) to be as high as 3:1 or 4:1. Don't be alarmed, this is normal. The feedpoint impedance for a loaded mobile antenna for 75 or 40 meters will be somewhere between 7 and 15 ohms. This will require some type of impedance matching at the feed point. There are several ways to accomplish this and all will work with some degree of success.

The easiest way we have found to handle this matching job is with the "Impedance matching coil". This coil is constructed so it can be easily held in place between the mast and the chosen mount. The matching coil is then tapped to antenna ground with the tap wire provided. By moving this tap up and down it is possible to achieve a perfect match of 1:1. Two or more taps will be required for full phone band operation on 40 and 75 meters. As a rule of thumb the matching coil will require 4 to 5 turns on 75 meters and 3 to 4 turns on 40 meters. 20 thorough 15 meters will require fewer turns and 10 and 12 meters will require little or no matching at all.  

Normally only one tap for each band will be required on the matching coil. One tap point per band on the loading coil will usually allow full phone band operation on 10 meters, 12 meters,

Please observe the following rules to insure maximum performance and life from your Texas BugCatcher.

1. We strongly recommend supporting the Texas BugCatcher as high up the mast as possible because of weight and wind loading. 

2. Because of water shorting between turns of the coil DO NOT transmit using more than 100 watts output when operating in rain or drizzle. This problem can be reduced when coil is tapped from the top down as shown in the drawing.

3. DO NOT transmit at any power level if coil is iced over. 

4. We CAN NOT be responsible for corona arcing due to power level being excessively high in relation to the mechanical size of the antenna

With normal care the Texas BugCatcher will give many years of excellant service when the above suggestions are followed

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