Main Trading Company 

Home of the 

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” 

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 efficiency 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 TapsAdditional 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 whip16 inch hat----- 48 inch whip12 inch hat ---- 59 inch whipThese whip lengths are intended as a reference only. The length of the whip should be kept as long as practical. # 440 COILThe # 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 

 # 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.

HD80 MATCHING COIL

As with all high “Q” mobile antennas (especially on 40, 75 & 160 meters) the feedpoint impedance is quite low. This necessitates some method of feedpoint impedance matching. This matching can be done several ways. An inductor, capacitor, toroidal transformer or other method can be used.Because of the ease of use we recommend the shunt inductor. The GLA Systems Heavy Duty Matching Coil is easy to tune and will match our antennas in all cases. It can also be used to match other types of HF antennas with great success.

The HD-80 matching coil is 2 inches in diameter and 2.5 inches long. The base of the coil is a solid piece of copper that is the full diameter of the coil. This copper plate has a 3/8” hole in the center that allows the stud of the mast to secure the coil to the mount. The coil wire is wound on a solid CPVC form. The coil form has a 1 inch hole in the center to allow the mast to pass through and secure the coil to the mount. This greatly increases the strength of the coil and also reduces coil vibration.

The coil is shorted to ground with a jumper and coil clips that are provided with the HD-80.