The original question was: can I make an emergency antenna from the (a) remaining coax (RG58 or alike).
Yes, assuming you can recover the coax e.g. pulling it from inside the mast
How you make it, without any soldering or complex manipulations:
- cut the free end of the coax cleanly
- for 156.800 Mhz, measure a length of 46 cm (18.1") on the outer mantle from the end.
- carefully cut the outer plastic mantle, pulling it off and exposing 18.1" of the braid
- just above the remainder of the plastic outer mantle, carefully pry open the braid with a fine tipped srewdriver or alike, until wide enough to be able to pull out the inner coax lead...if you are a bit handy this should work
- you will end up with your coax and on the end about 18" of outer barid and 18" of coax inner lead...
- there you have your 2 legs of your 156.8 Mhz dipole
- attach some thin rope
to a spare halyard
or maybe the topping lift
- tape the top of the inner coax lead at the top, the top of the loose outerbraid about 36" lower, and some more tape where both come out of the rest of the coax, there you have your emergency
- hoist it into the mast
as high as posible, just take care the braid part isn't touching the mast or any stays and at least try pulling away the coax a bit from the lower legg of the dipole, however, in a real emergency situation not really that important....
In all, about 10 minutes work and using the existing coax cable.
Off course it would be better to have a spare coax and a more sturdy emergency dipole at hand.