Wednesday, March 8, 2017

PL-259 Assembly Instructions

Conquering the PL-259
Walt Stinson,W0CP

New year's resolutions for hams.... Among the ones I've heard recently is "l will always solder the braid to the PL-259." That got me to thinking about what a hassle it is working with coax and PL-259's (not to mention hardline and N-connectors!).
Well, many years ago after consulting with Mr. Murphy, I made that same resolution. I faithfully followed the instructions for assembly of connectors in the Handbook. I remember using the tip of a nail to unravel the braid and trimming it with scissors.
Two moods would fall over me after a session of soldering 259's: Self-righteousness, for I was truly entering the ranks of the deserving; and klutziness, because about half the time l would have to cut of the end I was working on and start all over again. Sometimes, I'd forget to slip on the fitting cover. Other times  I'd have an intermittent after a couple of years.
Finally, after years of trial and error. I devised a fast and foolproof method of assembling the little buggers. If you follow my prescription, I assure you that you too will enter the ranks of the deserving (of course you will also need an antenna). This method is for RG-8u, but can be modified for other coax. Remember that foam style coax has a lower melting point and is trickier to work with. I recommend sticking with solid dielectric coax for this reason.

Gather up the following tools: (Buy these tools, if you don't have them!!)
Weller D550 240/325 watt soldering gun or Weller SP-120 soldering iron
1" adjustable pipe cutter (Rigid No. 104, available at hardware stores)
Tape measure with sixteenth inch scale
Razor blade style cutting tool
Triple core 60/40 solder, .047" diameter
Black fine point Sharpie pen
Household style pliers
Vise (pana vise)
Grease (dielectric, vaseline, pam, etc)
This method was developed for RG-8u. Remember that foam style coax has a lower melting point and is trickier to work with. I recommend sticking with solid dielectric coax for this reason.
Here are the steps: (POST THIS BY YOUR WORKBENCH)

1. Using the razor, cut off 1-1/8" of the outer insulation, exposing the braid.
2. Put the Weller on high and completely tin the braid
3. Measure 5/8" from the end of the coax and mark it with the Sharpie.
4. Using the pipe cutter, scribe the braid at the mark. Then, scribe the braid again 11/16" from the end. These cuts should be to the depth of the dielectric and no further.
5. Now, using the pipe cutter at the scribed point closest to the end, cut through the tinned braid and inner insulation. Be careful not to cut the center conductor. As you get closer to the center conductor, bend the coax a bit to expose the cut so that you don't nick the center conductor. 1/16 inch of the tinned braid should simply fall off at this point due to the second scribe. 
5. Twist off the braid/insulation & tin the exposed center conductor.
6. Slip on the PL-259 sleeve!!!
7. Screw the coax connector onto the coax using the pliers until the center conductor reaches the tip of the fitting. Put a dab of dielectric grease or vaseline on the coax insulation to reduce friction while screwing on the connector. 
8. Secure coax in vise. Heat a hole in the coax fitting. Apply solder through the hole, melting it into braid.
9. Apply solder through all holes. Keep fitting hot but work quickly to avoid melting coax center insulation. Don't flex while coax is hot, allow time to cool in the vise before flexing.
10. Solder the tip of the fitting and check continuity.

Since I have been using this method I have not had one intermittent problem. Moreover, my coax once got caught as I was raising my motorized crank up and the cable just about tore the tri-bander off of the tower! Fortunately, the coax was connected to a balun and a remote switch. The females were ripped out of both of these but my cable was unscathed. This proves another of Murphy's laws - solving one problem simply reveals another.

(PL-259 Assembly Instructions)

No comments:

Post a Comment