Comet VA-250 User manual

VA~250 Broadband antenna install a veranda
Instruction and assembly manual
Thank you for purchasing the Comet VA-250 Broadband antenna. For your safety and to
get the best possible results, we recommend that you read this manual to fully
familiarize yourself with the VA-250. Also, please keep this manual in safety place for
your future reference.
Features;
• It was compared with a usual antenna, and
the ultra wide-band property which
became stable was realized.
@ Thick base element(2mm) for heavy
duty operation.
©Utilizing stainless bolts and nuts for longer
life.
®An antenna wire kind can be used even if
Zeppelin form wire antenna is taken
because it is attached.
Before assembly;
Please make sure all parts are enclosed in
carton box as listed below.
No. Description
Qty.
1 Matching section assembly
1
2 Worm cramp for Aluminum element (1)
1
3 Aluminum element (2) with the element attachment lug
1
4 Top element
1
5 Top element with the reduction coil
6 U bolt (w/ lock washier, nut) 2
7 Antenna wire : 3.5 sq.mm (10m) 1
8 Insulator 1
9 Nylon rope (5m) 1
10 Self adhesive tape (20cm) 1

Specifications;
• Frequency Transmit 3.5 ~ 54MHz / Receive 2.0 ~ 90MHz
Recommend antenna coupler combination
• Max. Power 200 Watts ( SSB )
It is based on the power at the time of the intermittent transmit.
• Impedance 50 ohms
• V.SWR Less than 1.5 : 1 typical
• Connector SO-239
• Max. Length 8.4 ft ( 2.56 m ) / Max. Height : 2.16 ft ( 0.66 m )
• Weight 5.2 Ib ( 2.36 Kg )
• Wind survival 89.5 mile/Hr ( 144 Km/Hr )
• Mast size range 1.18 -2.8 in ( 3.0 ~7.2 cm )
Representative frequency characteristic figure;
Warning;
• Before you install your antenna, select the most available open site away from electric
power lines and telephone lines. To get the maximum performance from your antenna.
• Be sure to wear a safety hat, safety belt in case of a high behavior industry so that drop
accident desperation may be prevention. An antenna should fail down and drop, and
install it in the location not to give a person and a building harm.
Assembling;
1. Thrust a top element in the fitting screw hole in the top of Pipe (2), and fasten a fixed
Lock nut.
2. Face a red seal side toward the bottom, and install an top element with the reduction coil
in the same way.
3. Loosen and fix a Hexagon head screws (M6 X 8).
4. Use a U bolt, nut for your pole and so on, and fix an antenna itself.
5. Connect your 50 ohms coaxial cable to the female connector of the matching section, and
connect it.
6. Confirm Standing-Wave Ratio value Less than 1.5
Use an antenna coupler with 3.5~ 14-MHz together.
7. Use the supplied self-amalgamating tape to waterproof the connector.
make it waterproof.
* Frequency can be tuned in the amount of insertion of Pipe (2) exactly.

[In case of Zeppelin form wire antenna]
Frequency characteristic
example figure of 7m;
Assembling in the wire;
1. Loosen a fixed screw in the bottom
of the element attachment lug, and
tighten it as the figure with the
terminal of the wire.
2. Pass the terminal of the wire through
the insulator, and fix it in the plastic
band and so on.
3. A nylon rope has already been passed
through one hole, and spread it in the
optional position.
ft A characteristics changes by the wire
installation requirements.

Note & Remarks on handling and driving:
• Never touch or adjust the antenna while transmitting. Otherwise, severe
injuries including burn may result.
• When a lightning is observed, stop operating with the antenna. Don't touch
a coaxial cable and so on because it is sometimes struck by electricity.
• Please confirm tight fastening of connector and screws, etc. of antenna.
Loosening and falling off will lead to personal injury and property damage.
• Please adjust antenna correctly. Irregular VSWR will lead to heat-up,
break-down or power-down of antenna.
Note & for operation:
• T his antenna is for amateur radio and Broad Band receipt operator. Do not
use other than for the purpose of antenna.
• Please use this antenna within the standard and specifications described in
this manual. Failure to this may cause heat up and break down of the unit.
• Whatever damage and the malfunction which is due to the repair and the
reorganization at end-user itself occur, it doesn't take the responsibility.
• Recommend antenna coupler combination when you transmit in 3.5~14MHz band.
Be careful of the transmitting power, time because it is being based on the power at
the time of the intermittent transmit.
[Maintenance]
• If mal-function is occurred, stop operation and try to find the reason. If it is not settled,
please contact the store/shop where you purchased the antenna or our Engineering
Department.
• Before the practical use when transmitting, please check the VSWE is less than 1.5 at
your operating frequency.
• Routinely, please confirm tight fastening of each Screws, clamp, etc.
[ Customer Service ]
• Replacement parts and accessories are available at our dealer and our factory.
• This quality product is manufactured under strict quality control.
contact the store/shop for those damaged by transportation.
• For further information about assembling work and other technical matters, please
contact to our Engineering Department.