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Jetstream RG 8/U JT2015F coax does not fit PL-259 problem

Discussion in 'Antennas, Feedlines, Towers & Rotors' started by WB6IZG, Feb 23, 2018.

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  1. WB6IZG

    WB6IZG Ham Member QRZ Page

    I have an interesting problem and would like ideas from the ham community. I recently bought some Jetstream JT2015F RG 8/U 671704 Low Loss Foam coax. The center conductor is stranded. To my surprise the center conductor will not fit onto a PL-259. I am using am Amphenol 083-1SP-15RFX connector. I have tried tinning the center conductor but this makes the problem worse since solder goes between wires and causes it to bulge a little making problem worse. My only recourse will be to clip about 4-5 strands from the center bundle. I have used the Amphenol connectors on Belden 9913 before with no problems. I have been a ham for 35 years so have experience with coax and connectors but have never seen this. Any ideas would be helpful. Are there connectors with a little bit bigger center conductor opening?

    Thanks,
    Bruce, WB6IZG
     
  2. WB2WIK

    WB2WIK Platinum Subscriber Platinum Subscriber QRZ Page

    To answer the last question first: No, there aren't.

    The trick to using that cable with a PL-259 is to NEVER tin the strands (makes it worse, as you noted), but expose (strip the dielectric off) the center conductor much, much longer than it needs to be -- even a few inches is great -- and softly twist them together while pulling on them, to stretch them out. Never "tightly twist," that makes the bundle larger.

    Also, make sure when you cut the center conductor don't use "diagonal cutters" (like "dikes"), as that pinches the tips of the wires and slightly flattens them, making them larger: Use a real wire/cable cutter, which is mating and overlapping very sharp "half moons" that are semicircular and don't have flat, straight cutting edges. That prevents "pinching," and just slices through the wire instead, leaving it it's original diameter.

    Using a real cable cutter (sharp), exposing inches of center conductor more than you'll ever need (you trim it off, later, after the connector is assembled), and gently twisting the strands makes it absolutely possible to get the entire strand bundle through the PL-259 center pin.

    Done this hundreds of times.
     
    NH7RO likes this.
  3. WG8Z

    WG8Z Ham Member QRZ Page

    I had some of the jt2015f.
    Just reamed the center pin with a drill bit
    Doesn't take much it's only a couple of thou.
    Done deal.
     
  4. WB2WIK

    WB2WIK Platinum Subscriber Platinum Subscriber QRZ Page

    I wouldn't do that, when simply trimming the center conductor properly (as above) works fine.

    The center pin of a PL-259 is only 24 gauge brass (plated or tinned) and not very strong; making it thinner can result in bad things happening.

    There's nothing wrong with the connector or the coax; the thing that's wrong is the "coax prep" if not done exactly as it needs to be done.
     
  5. WG8Z

    WG8Z Ham Member QRZ Page

    Thats what I thought Steve until until I put a mic. on the cable.
    Bottom line the jetstream cable center conductor varies not only from batch to batch but also throughout it's length. Depending on where you cut it may or not fit. Yes I did use a proper cutting tool.
    Just my experience.
     
  6. WB2WIK

    WB2WIK Platinum Subscriber Platinum Subscriber QRZ Page

    Well, you might be right about "Jetstream" cable.

    They don't manufacture cable, they're just a "brand," so the cable is made by "somebody" and then labeled for them. I don't know who makes it.

    But usually, if you make the center conductor VERY long so it can go through the pin and exit the pin before the rest of the coax even engages with the PL-259 connector, so you can "see" exactly what's going on through the connector solder holes, and if you gently twist the conductors while pulling on them to stretch them, the assembly will go okay.
     
  7. WB6IZG

    WB6IZG Ham Member QRZ Page

    WB2WIK, thanks for the advice it worked. Using a circular cutter instead of a flat cutter helped a lot. Also at the end I had to gentle massage a couple of stands into the bundle that had breaked away a little bit.

    Bruce
     
    WB5YUZ likes this.
  8. K8ERV

    K8ERV Ham Member QRZ Page

    Luvit when a plan comes together

    TOM K8ERV Montrose Colo
     

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