background image

 

 

four bolts also serve to fix two tube clamps.

 

(   ) Take the aluminum plate (fig. 5) and insert it into the underside 

 

(   ) Note that  the two L-shaped plates will  be at the bottom  and its 

 

 

If  necessary, lock the nuts in position using pliers.

 

 

of the previously assembled set between the "

L

" plates.

 

 

(   ) Using a 10mm (3/8 inch) wrench securely  tighten all  hex bolts. 

 

 

(   ) Pass two M6 x 25mm hex bolts (small), two flat washers, two 

 

 

spring washers and two nuts.

 

(   ) Use four  of the six  remaining holes to secure the set to a  38  to  

 

 

ly need to use 4 holes to keep the assembly tight and secure.

 

 

"U-64" clamps provided. The plate has six holes but you will on  

 

 

 

suggest that you keep the central support  always mounted to fa- 

 

 

(   ) Tighten firmly so that the set is very stable and fixed. 

 

(   ) Keep the antenna as high as you can reach to finish mounting. 

 

 

64mm  (1-1/2" to 2-1/2") telescopic pole, mast or pipe.  Use two 

 

(   ) If your intention is to use this antenna in portable operations, we 

 

 

cilitate temporary installation.

Figure 5

Aluminum plate

Side view of the center 
support already with clamps

8

 

(   ) Repeat the same operation on both ends of  all bands from 10  to  

 

 

marking  represents  the approximate  center  frequency  of each 

 

 

wires about 40 cm (16") over the tube in the inner direction and 

 

 

spacer must be installed symmetrically.

 

 

2 or 3 holes as shown in photo 4.

 

(   )Do  not pull  excessively to  avoid straining the  end of the  fiber 

 

(   ) Place the plastic spacers at the ends of each band wires.

 

 

secure  (Point B in figure 9)  with a  releasable  cable tie.  Allow   

 

(   ) Pass  the wire  through the first hole  of the spacer and pull  until 

 

(   ) Using the plastic tighteners, stretch the five ropes so that the ele- 

 

 

ments are slightly up.

 

(   ) In the case of the 6 meter antenna (the innermost one), align  the 

 

 

excess of wires to hang downward.

 

(   ) Note  that at the  end of  each  wire there is a yellow mark.  This 

 

 

band.

 

 

reaching the mark.  Pass the wire  through the third  hole so  that   

 

 

the spacer does not come loose.  Braid the rest of the wire every  

 

 

tubes. It is normal for the wires to have a sag.

 

 

40 meters.

 

(   ) For 10, 12, 15, 17, 20, 30 and 40 meters antennas, a plastic band 

Photo 4 - How to attach the wires to the spacers

13

Summary of Contents for RH-DX640

Page 1: ...ASSEMBLING INSTRUCTIONS MANUAL Antena RH DX640 Cobweb Antenna for portable or base station operation in 6 10 12 15 17 20 30 and 40 meters ...

Page 2: ... 10m band 28000 29700 kHz 12m band 24890 24990 kHz 15m band 21000 21450 kHz 17m band 18068 18168 kHz 20m band 14000 14350 kHz 30m band 10110 10150 kHz 40m band 7000 7300 kHz Braid the cable through the central plastic insulator as above Do the same on both sides 2 Return the remainder of the wire so that it is adjusted according to the frequency of each band above wire hanging dropped NOTE The fre...

Page 3: ... feet off the ground 14 2MHz Minimum SWR 1 1 Impedance 50 Ohm Conector PL 259 with coaxial cable 50 Ohm Weight 5 5 kg 12 1 lbs Dimension 540 x 540 cm 212 x 212 inches TECHNICAL SPECIFICATIONS Type Omnidirectional Cobweb Reception 500kHz to 50 000kHz 50MHz Transmission 6 10 12 15 17 20 30 and 40 m Wind resistance Moderate to strong winds Mast diameter 38 to 64mm 1 1 2 to 2 1 2 MW and SW reception re...

Page 4: ...kHz Youwillneeda lotof patience preference Rememberthata fewinches canmovethe ressonant frequencymanykHz yourpreferenceandtrytoadjustitinthatsegment ofjust100kHz 28 068 to28 168 kHz Adjust inthe centerof the band In20meter 14 000 to14 350kHz adjustinthesegment of your The3 0 meterbandistheshortestofall Withonly50kHz 10 100 ly100kHz from24 890 to24 990 kHz Afew inchescanmove Incaseofthe12 meterante...

Page 5: ...tening elements 3 Releasable Cable Tie nylon 8 Tube clamp 25mm 1 inch large 24 Snap Rivet nylon 5 16 Startby setting the6 meter band 50 to 54 Mhz Startchecking vethereleasablecabletie furthertowards outsidethecenterofthe youprefer movethecable tietowards theinnerofthecenter cau antenna If thefrequencyisabove54MHz orabovethefrequency In a first step check the resonant frequency of each band If it s ...

Page 6: ... thatwhen raisingtheantennaitisnottooclosetoobstaclessuch as This antenna has limited badwidth with an acceptable SWR Thus it is important that you define which is the preferred segment of operation in each band and try to leave each band adjusted to your preference But you will have abetterresultusing andantennatuner BASIC RULE TO ADJUST Higher frequency Decrease the length Lower frequency Increas...

Page 7: ...upthe4 telescopicfiberglass masts Keepthemclosedandin Figure 3 Figure 4 Insert each mast until they get close with the limit of the clamps 7 14 Connect a good quality 50 Ohm coaxial cable with the shortest possible length between the antenna and the radio Roll up a ba lun on the coaxial cable itself keeping the coils together with Secure the coaxial cable to the matching box tube with the last tape...

Page 8: ...lation Figure 5 Aluminum plate Side view of the center support already with clamps 8 Repeat the same operation on both ends of all bands from 10 to marking represents the approximate center frequency of each wires about 40 cm 16 over the tube in the inner direction and spacer must be installed symmetrically 2 or 3 holes as shown in photo 4 Do not pull excessively to avoid straining the end of the ...

Page 9: ...o that they are not damaged sembly and disassembly be careful when removing the rivets Photo 1 Detail of the positioning of the small holes placement and removal of the nylon snap rivet A Fix only one hex nylon bolt and nut B Fasten with a releasable cable tie C Thread the rope through the nylon clip and fasten together with the fastening element D Thread the rope through a nylon clamp and secure ...

Page 10: ...ght of the wires it is natural for the tu of the plate Simply screw the mast firmly band fastening element the larger antenna using a nylon clamp Release all five ropes The shorter rope must be attached to the Connect both sides respecting the identification Pass all the wires inside each of the nylon clamps according to Identify the 5 wire antenna pair 15 17 20 30 and 40m that must be attached to th...

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