• You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
  • Click here to find out how to win free radios from Retevis!

Cold Solder Joint?

Yankee

Active Member
Apr 15, 2013
307
22
28
Can a cold solder joint on a PL-259 connector on a jumper cable cause an amp to show high SWR? I don't know enough about theory and don't want to get into another discussion about it, but could that be one obvious cause?
 

Just wondered. It seems to be fine under low power, then it goes way up with lots of power. I fixed those joints though, with a much heavier duty gun. Melts that stuff right now. Didn't make much difference though. :)
 
I have the R450,the granddad of this puppy. Can be used for light gauge spot welding as I remember. Good for something big and thick to solder. Namely PL-259 connectors. You have to be cautious though the isolator will melt and distort if you hold it on too long.

R450B, Kit, Soldering, 25/450W

Some sites say that if your connector is nickel plated that you should sand those areas down to the brass that you want to solder. I haven't. I use brute force(heat)
 
Last edited:
Those sites were right about sanding or filing down to the brass. Brute force is not the way to do it. All it takes is a couple swipes of a file. Better yet pay the extra dollar and get silver plated connectors.
 
Last edited:
  • Like
Reactions: 1 person
Those sites were right about sanding or filing down to tbe brass. Brute force is not the eay to do it. All it takes is a couple swipes of a file. Netter yey pay the extra dollat and get silver plated connectors.

To be honest I only found out about that recently when I soldered some connectors on my feed line. Thanks for explaining how to do it.
 
I have done a lot of soldering over the years, and was trained to do it by old Ma Bell of the Chesepeake area, and got years of practice doing it afterwards. I also did buy the silver coated connectors, but I still think it's worthwhile running a file over them, which I did not do this time. However, the way the solder flowed into the holes was a pretty good indication that it "took" this time.

Lil'Yeshua, the Weller 200/260 seems to be hot enough that you do not have to take so long doing it that it heats up the whole connector. That's why I don't like the liteweight gun I was using, it melted solder, but it had to heat the whole connector to do it and still did not "draw" the solder in. This new gun does it in just a few seconds. And I thought of it, but forgot at the end, to use a square of folded up wet paper towel to cool the connector down after soldering. That should help save the teflon insulator.

By the way, I am glad I checked my local Ace Hardware. I found the Weller gun, a kit box with some solder and two extra tips of different sizes, including the big hefty chisel tip that was mounted in it. And are you ready for this, it was $20 cheaper in the store than anywhere I found it in 4 days of searching online. (y)

Thanks guys for all the comments, I learned something again. :)
 
I also did buy the silver coated connectors, but I still think it's worthwhile running a file over them, which I did not do this time. However, the way the solder flowed into the holes was a pretty good indication that it "took" this time.


Since silver is a better conductor than brass the last thing you want to do is file away the silver to solder to the brass. I use solder with 2 or 3% silver content when soldering any RF connections whenever possible.
 
Where do you buy these special blends? They sure don't have them at Ace. LOL

I have worked with silver/nickel and different blends of silver, but it was supplied by the places I worked.
 
Yeah; that new fangled leadless solder being sold today is for the birds. Like trying to solder with peanut butter. Because it has no lead in it, it takes a hotter iron - which can be bad for the parts and the board traces if not careful.

My solution is to buy solder from the local hamfest, which one vendor sells and is all lead based. Gonna buy two rolls this time out so that I will have enough for a while. Because it is getting rarer and rarer. Maybe get a 1 lb roll with silver this time around too.

Reworking these newer boards with the non-lead solder has been troublesome. One solution that I've found when attempting to remove parts is to add some lead solder to the joint first; then use the solder sucker to pull it all off. This works outstanding, but of course you end up using more solder in the process. But the trace will come clean this way.

While still on a rant against this non-lead solder; there is one more point. I recently had to fix a couple of computer flat screen monitors that had bad caps in the power supply - a common problem and a relatively easy fix. Just replace all of the electrolytics in the PS; the cap kits are sold on fleaBay. But I did find another problem there too. The 110vac power plug on that supply had cold solder joints to the board. Adding some lead solder to the existing tin joints fixed it right up and got it working again.

Many laptops have a problem with the power plug for the very same reason. Plugging/unplugging the power cord to the laptop will eventually ruin the joints on the board. The only remedy is to take the whole laptop apart - just to get to the problem connector! Oh; fuuuun. But the fix is the same. Add some lead to those joints and it is right as rain again. Also, scrape a little of the board varnish away from these joints until you see the gleam of fresh copper before you solder - for a slightly larger solder pad. That did the trick. Imagine that silver solder used here would be even better still; simply because silver adds tensile strength and is an xlnt conductor . . .

The wave of the future . . . lol . . . end of rant . . .
 
Last edited:
Where do you buy these special blends? They sure don't have them at Ace. LOL

I have worked with silver/nickel and different blends of silver, but it was supplied by the places I worked.


First a note to Robb.......don't even get me started on that lead-free solder crap. :censored: I have been soldering for almost 40 years and I absolutely HATE the lead-free stuff. If left for a while the new solder will actually take on a yellow/brown colour rather than stay nice and shiny. It also has poor wetting qualities.

As for where to get silver solder....Radio Shack used to carry the 2% stuff. Kester makes a good 3 % solder and should be available at any electronics parts supplier. Hardware stores generally may or may not carry such stuff as they are not usually the go-to place for such items. I buy mine at RAE Industrial Electronics which is a semi-local industrial electronics retailer here but any place that carries Kester 44 solders should be able to supply it. I use an alloy consisting of 61.5% tin 35.5% lead and 3% silver.

Soldering tools & supplies - Tools & soldering equipment - RadioShack.com
 
  • Like
Reactions: 1 person
R/S 2 oz. solder. 64-018
This Clear Flux Solder provides better-looking results, holds shapes and dries smoothly. It's high strength is ideal for projects and design work. It is designed to repair joints on circuit boards in PCs, TVs, VCRs, CBs, Ham radios or other electronic devices. Made of rosin-flux core, it is 60% tin and 40% lead, with a .063" diameter.
Great for projects and design work
High-strength solder provides better-looking results holds shape, dries smooth

Where's the silver?
Got lead

R/S 64-013

This special rosin core solder is ideal for surface mount devices. It has a 62/36/2% tin/lead/silver formula with a .022" diameter. 1.5 oz. spool.
 
Last edited:
Not sure what happened but that is not what I li.kef too. It should have been just a roll of 2% silver content solder. Just search the R/S site for solder and you will find it.
 
Many laptops have a problem with the power plug for the very same reason. Plugging/unplugging the power cord to the laptop will eventually ruin the joints on the board. The only remedy is to take the whole laptop apart - just to get to the problem connector! Oh; fuuuun.

Wanna talk about fun? My Playstation 3 refused to boot up, the yellow light of death they call it. What happens is the CPU or the GPU starts to pull away from the circuit board.

There is a nifty fix online involving heating the area of the chips with a heat gun to get the solder reflowed around the pins.

Didn't work on mine. I had to get the iron out and resolder those surface mount chips to the board. You know how many pins there are on those chips? A shit load is the correct mathematical term.

That playstation gets as much use as the TV. It's our DVD player, Blueray player, Netflix, Crackle, and Hulu. So it was worth the time invested. At least according to my wife.
 
  • Like
Reactions: 1 person

dxChat
Help Users
  • No one is chatting at the moment.
  • @ Mark Malcomb:
    Hello BJ. Been a long time since I've been on. You doing well? Mark Malcomb
  • @ Naysayer:
    I’m
  • @ kingmudduck:
    Hello to all I have a cobra 138xlr, Looking for the number display for it. try a 4233 and it did not work