Posted by: andy idsinga | May 23, 2010

My DIY HDTV antenna

Here’s a little HDTV antenna I built recently.

Psst – it could be used to receive regular old tv and other radio transmissions too :)

I built it after reading this page that describes the shoebox HDTV antenna. Why did I not just build the shoebox antenna? I dunno – I just had to do my own thing :)

Okay, so the antenna works pretty good here in the Portland OR area and it will likely work good for you too if you are within 8-10 miles from your local TV stations.

It is a very simple dipole antenna with two 36″ lengths of 12 gauge copper wire. The exact same copper wire that is run inside the wall of a home for 110v electricity. You can buy it at many hardware stores.

Why did I choose 36″?
Well, the shoe box antenna above indicated that 6″ minimum was required. That length is important as it’s related to the TV frequencies being received.
I just multiplied 6″ by a number ( x 6 ) I pulled out of you know where to make it longer and hopefully get better reception.
The reality is that this 36″ length is not really correct and to make it correct I should go back and read my ARRL Antenna book and figure out the right wire length to support receiving the TV frequencies in my area.
…maybe later because this is one is actually working ;)

Why did I wrap the wire around in that funky pattern?
I vaguely remembered reading something about that pattern having a positive affect.
Reality: After talking to a friend about it and getting a really weird stare, I’m pretty sure I was remembering something completely fictional and I don’t think it has an affect other than to get more wire on the piece of plywood.
Again, consulting the ARRL Antenna book is the way to get that kind of thing right.

Materials and tools:

  • 2 36″ pieces of 12 guage copper wire
  • 75 Ohm coax connector
  • 75 Ohm female to female coax coupler
  • A splitter that passes frequencies from 40Mhz to 2Ghz
  • A piece of scrap plywood
  • wire snips
  • A soldering iron and solder. Note: I use a 45Watt soldering iron that looks like this
  • A hot glue gun and hot glue sticks

A couple pics of materials and tools:

I put temporary screws into the plywood and used them to wrap both wires into the desired pattern. (again – this pattern is meaningless – I just made it up).

I soldered one of the copper antenna wires to the tiny pin that sticks out of the middle of the coax connector. I soldered the other wire to another small wire (the red thing) that I then wrapped around the outside part of the coax connector.

I then mounted the pieces to the plywood using hot glue.

The finished antenna:

…and mounted on the back of my desk using double sided mounting tape. It turns out my desk is pointed in the right direction for all our local TV stations. If your TV stations are not in a single direction you might consider mounting it to a tripod so that you can aim it and get better reception.

By the way – I used a splitter so that I could attach my single antenna to an HDTV receiver with two tuners. So far it is a great product: Silicon Dust HD Home Run. I use it with a PC connected to my TV.

Advertisements

Responses

  1. This is pretty cool!
    I wanted to drop you a note while I was travelling but realized after I left that I don’t have your contact info on any of my mobile devices. But I did remember you had ablog. Ha!

    We’re in Washington dc seeing the sights. Smithsonian was excellent. Private audience with the president not so much. (grin).

    Hope to see space shuttle and Anola gay tomorrow.

    Take care

    Tom

  2. Andy idsinga Hello, good morning.
    Congratulaions to the antenna!
    Dear me know how to have mediated the dipoles of the antenna or the measurements of the marks on the wood?
    Grateful for attention.
    alkynes

  3. […] my research, and found some interesting articles. There’s lots of info out there, but I like this gentleman’s implementation the best.¬†¬†There wasn’t any science behind it, but it was the shape that got […]


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

Categories

%d bloggers like this: