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Balun and Isolator Assembly  Assemble the UHF connectors(3) and associated hardware into the Balun box and  Isolator  end caps. (Not the #22 gauge wire yet). The UHF connectors use # 4 hardware (4-40 machine screw, flat washer, ring lug, star washer and hex nut). The ring lugs are the long thin ones with two holes. Assemble the stiffener plate (1) and associated hardware into the Balun box. (Not the #22 gauge wire yet). The stiffener plate uses #6 hardware (6-32 machine screw, circular lug, split washer, hex nut, flat washer, split washer, hex nut and wing nut). The supporting eye bolt uses #10 hardware (hex nut, split washer, flat washer, split washer and hex nut). The circular lug (two supplied) are the small ones with one circular hole and a tubular hole. Note: Bend the ring lugs so that they are 10 mm high as measured from the UHF connector. Make sure that all hex nuts firmly tightened against their mating washers Balun Assembly See instructional videos: Video1  and  Video2 by Barry, VE3NJK Use a piece of RG-316 cable(Double Braid) 770 mm long. Place two tie wraps on the toroid. Do not tighten them as RG-316 will be inserted through them as you wind the toroid. Wind the Balun Toroid using RG-316 as described by VE3NJK. Use 11 turns. Strip and tin both ends as shown below (Stripping RG-316 Cable).                                                  Place two layers of masking tape over the Balun Box edges and the Isolator end caps. Solder one end of the #22 gauge (44 mm) solid wire to the top right solder lug on the UHF connector. Carefully solder the center conductor into the UHF connector (Push the dielectric right up to the connector). Wind the #22 gauge wire around the RG-316 braid and insert it into the other solder lug and solder. Secure the tie wrap fastener with super glue (wear gloves).  Attach the 8 inch tie wrap. Bend the long end of the RG316 into a smooth curve as shown in the picture above. Solder the center conductor into the top left circular solder lug (see photograph above). Solder a  short piece of #22 gauge wire into the top right circular lug. Solder the #22 gauge wire onto the RG-316 jacket as shown in the picture above. Check for continuity and shorts with a multimeter. Isolator Assembly Cut a piece of RG-316(SINGLE BRAID) to 890 mm long. Wind the Toroid: 11Turns, RG-316,  (Wind counter clockwise, pass the cable through the core at turn #6). Place the stripped end of the RG-316 150 mm from the outer edge of the toroid. Secure with a 4 inch tie wrap.Trim the other end to 160 mm, strip and tin this end.  Secure with a tie wrap as before. See the photograph below. Place masking tape over the end caps. Secure the Toroid onto the support plate with a tie wrap. Solder a piece of 44 mm of #22 gauge solid wire to a solder lug in an end cap Solder the center conductor  of the RG-316 into the UHF connector Wind the #22 gauge wire around the RG-316 braid and insert it into the other solder lug. Solder the wire to the lug and the braid.    Check for continuity. Insert the assembly into the isolator tube Repeat the end cap process for the other end and place the end cap on the tube. Check continuity and shorts.
Note that the edges of the cap must be protected with masking tape before any soldering. Note that the edges of the cap must be protected with masking tape before any soldering at the next stage of assembly.
44 mm of #22 solid wire Solder to top right lug Wrap around coax braid Solder to remaining top lug Solder to braid
Use a 14 gauge wire stripper for the jacket...Single Braid Use a 12 gague wire stripper for the jacket...Double Braid Use a 26 gague wire stripper for the center conductor Practice stripping RG-316 with a sample supplied. This takes a bit of practice.  Tin the center conductor and the braid Jacket Stripping RG-316 Cable The most important dimension is the length of the center conductor (5mm) which must fit into the connectors. Keep to 5 mm +/- 1mm. The other dimensions are a bit less critical.
1. Strip the outer jacket back 13 mm. 2. Tin the outer braid completely around. 3. Mark the braid 5mm from jacket with a felt tip pen. 4. Scribe the braid using a wire stripper * and then bend the outer portion of the braid until it breaks. 5. Remove the braid. 6. Mark the dielectric 5 mm from the end of the cable. 7. Use a 26 gague wire stripper to cut the dielectric. 8. Remove the dielectric and tin the center conductor. *  Use a #14 gague wire stripper for double clad coax and #16 for single clad to scribe the braid
35mm Every time a wire passes through the center of the toroid,it counts as ONE turn Approximately 140mm 11 Turns: Count them
Turn#1
Turn #7
Turn #11
RG-316 11 Turns 890 mm long One end 150 mm long One end 160 mm long Two Tie Wraps