this is how i built my first antenna for HF its quick and dirty keep in mind that if you want a dipole that is going to last years and years do it the right way with a proper balun center insulator and proper end insulators but as a new ham you most likely will be experimenting with many antennas and moving through them quickly so it makes no sense to spend a huge amount of money on each one.
If you have some way of checking swr so you can tune the antenna then this antenna is a breeze allot of your modern radios have a swr meter built into them if your running an older rig like me then your going to have to beg, borrow, or steal a swr bridge when i built this antenna i borrowed one from a local ham and he ended up letting me hold on to it as a long term loan sorta deal.
anyway what your going to need is a so-239 panel mount a machine screw and nut to fit one of the mounting holes in the so-239 i small piece of rigid plastic i used a piece of the lid of a tidycat bucket about 3 x 3″ square this will be your center insulator . your going to need some insulated wire most any wire will do you can get 75ft rolls of 2 conductor 20 gauge speaker wire for less than $10 you can measure out enough for 1 side of the antenna cut it then split the 2 conductors apart use one conductor for each half of the dipole
this dipole can be made for any hf band within reason using this calculator 20 meters for a first antenna for a new general be a good place to start or 10m for a tech looking to get on the tech portion of 10M
use the dipole calculator linked above to decide how long to make the wires make sure to make your initial cut long because you are going to tie the wire though holes in your center insulator then attach the wires to the so-239 one side with the bolt the other side will have to be soldered to the center pin.
because the wire is insulated we do not need end insulators just bend the wire over in a loop and tie non conductive rope to it. believe me i had this antenna up an entire winter swr never changed.
calculate your antenna long to start and shorten equally on both sides until swr is good. word of warning though if you have more than a couple feet of wire bent under and the end not shorted back onto the main radiator say for instance you built it for 20M but you want to experiment with 17m so you try to shorten the antenna by folding the extra wire under. well i tried that and after a certain point swr goes crazy unless you strip a bare spot in the main wires and short the ends of what is folded under to it.
you will need to wind a 1:1 choke balun in the end of your coax to do that measure out 10 feet of coax in the end of your coax a few inches from the connector were it connects to the antenna then wind that 10′ into 7 equal flat coils and tape it up make sure the the end of the coax going to the radio and the end going to the antenna are on opposite sides of the coil and do not touch. this is directly out of the aarl handbook 2004 edition. this will work with rg-58 rg8x and rg-8 coax and is multi band but works better on 10m-20m i am told
as far as coax if your building this for 10M get good coax but for 20m or 40m if your on a budget rg-58 will work on 20m over 100′ of rg-58 would be about 1.4db which means your getting 71watts to the antenna stepping up to rg8x would only get you 4-5 extra watts at the end of the cable on 20m and rg8x is twice the price usually.
the cheapest way to get coax is to buy just the coax no ends and buy solder on pl-259 ends and adapters then find a local ham to teach you to solder them on. or you can buy a crimping tool and use crimp on ends.
if your going to leave the antenna out in the weather tape the so-239/pl-259 connection with the weatherproofing method of your choice. electrical tape will work fine for the short term.