Originally Posted by xtreme
I had to cut my gps cable and radar cable will i have to replace them or can they be re-joined
Looking forward to your replies
You can join your cables.
The GPS cable may or may not be screened. If the gps cable is just linking an antenna to the gps head unit then the cable will be a single screened cable; probably 50ohm impedance. If the cable is linking a gps engine to the head unit the cable will have multiple cores and may also be screened. You may also find a bare drain wire in there against the shield.
The radar cable will be multi-cored and most likely will have an external screen and separate screened cores. Along with these will be power and ground cores. These may be doubled up because the scanner unit will draw biggish current in pulses and the double power and ground cables will limit the voltage drop during the high current draw.
Joining the plain cable is straightforward. On each one, strip back a couple of millimetres of insulation. Tin the ends, slide a piece of adhesive lined shrink sleeving over one cable end, solder the tinned ends, place and shrink the sleeving. Repeat as necessary.
Joining the screened cable is a little trickier. I fold back the screen on both ends for about 15mm. Slip some shrink over the cable outer. Shorten the inners to about 8mm and tin just about 1mm on each centre conductor leaving a wee blob of solder on one of them. Next, solder the tips together and quickly push them together while they are still hot. The hot ends will push up inside the core until the cores butt and become virtually continuous. The wee blob of solder retains the heat for long enough for you to do this, (if you're quick
). Having a helper makes it easier.
Ensure it's well done, bring back the screen from one end and smooth it. Bring back the screen from the other end to form an overlap. Give it a wee touch of solder just to ensure a sound connection of the screens, then slide the shrink over the top and shrink it. A modification of this technique will be needed to complete the final screening over the bunch of jointed cables. Some or all of the shielding could be aluminium foil so, if that's the case, you'll need to re-wrap it the best you can. Shrink sleeving or even pvc tape can be used to hold it in place.
To limit the overall size of the jointed cable due to the extra material used in the jointing process, stagger the cutting of the cable ends so the joints don't coincide with each other.
The whole lot needs protecting and you'll need to plan how you wish to do this before you start jointing. If there is plenty of space then a waterproof junction box can be used. Glands will seal the cable to the box. If it's more of an in-line joint you need then there are cable connection pieces which are essentially a section of tube with a gland nut at either end. They are fitted to the cable prior to the jointing and then the tube slides over the joint. The glands are screwed into the tube ends against O-ring seals and finally the gland nuts are tightened to seal to the cable outer. They can be permanently submerged in water so I'd guess would be fine for your purpose. They come in various diameters to suit the cable.
I'm presuming you have soldering skills, of course. If not, then a respectable joint can be made using terminals within a junction box but you'll loose the shielding and the impedance of the screened cables will be compromised. Crimp or screw terminals are never as electrically sound as soldering is.