Introduction: Total DTV for Less Than $20
The recent change to the way broadcast television is transmitted has got a lot of people freaking out. This Instructable is a start to finish guide to getting your current television DTV compatible and fully functional. If you already have a DTV compatible television then the steps regarding the Converter box can be ignored.
Overview
1. Get Converter Box Coupon
2. Quench your thirst
3. Amazon a Box
4. Collect a few materials
5. Voila!!!
Step 1: Get a Converter Box
1. go to https://www.dtv2009.gov/ before the end of July 2009 and apply for a coupon.
2. When you receive it purchase a converter box
- I bought a Tivax STB-T8 Digital to Analog TV Converter Box at http://www.amazon.com
- After the coupon and saver shipping $9.99
Step 2: Quench the Thirst
First you must get two can's of Arizona Ice Tea or equivalent sized aluminum cans.
Okay, I don't recommend drinking 2 of these 23.5 ounce cans of Ice Tea in one sitting, but who am I to argue if you are this excited.
Technical Details
I found a similar design using two halves of a beer can, I have since forgot the site. But I did some digging and found some information to help me design this and figure out why it works.
UHF (Ultra High Frequency) is the frequencies that the FCC has reserved for the new Digital Television Formats to be transmitted on.
These frequencies range from 300Mhz to 3,000 MHz (3Ghz). This means the wave ranges from 10cm to 1 meter in length, making two of these aluminum cans end to end along with some 18 gauge speaker wire a perfect way to intercept these waves
Step 3: Cut Your Can
Cut 1/3 of the can away.
I haven't really tested effect of the cutting the can vs leaving it whole has on the signal quality, but I can say that the 2/3 of Aluminum Can is how I cut it and I get excellent signals in a basement.
Feel free to experiment and comment on this.
Step 4: Wire the Cans
Note:Check Step 5 and 6 before wiring the Can, you may want to feed the speaker wire into the tube first
Get a 10 foot section of 2 conductor speaker wire. This can be picked up at any local electronics store i.e. radio shack.
1. Peal the two conductors apart at one end about 5 to 10 inches (or what ever you are comfortable with).
2. Strip each conductor 1.5 to 2 Inches
3. Loop them securely around the tab of the cans (one conductor to Can 1 and the other to Can 2, see image)
Step 5: Acquire a Tube
Not a necessary step, but a cardboard tube makes a great home for this. (makes it look less messy)
Many companies that handle their own shipping may send and receive items in these tubes, so ask your company or a local small business if you don't want to buy one.
approximately 3 1/4 inches in diameter
Step 6: Drill a Wire Hole
Using a drill, make a small hole in the center (end to end) of the tube and feed the loose end of the speaker wires through the hole.
You may find it easier to feed the speaker wire prior to connecting it to the Cans
Wire the loose ends to a terminal to coaxial connector ($4 or $5 at radio shack)
Step 7: Connect Your New Dipole Antenna
Connect your newly created antenna to your converter Box or your DTV.
I'll Post images of the signal Strength on both my converter box and my DTV when I get a chance.
$2 for Ice tea
$9.99 for converter Box (Shipped)
$4 for Antenna Connector
<$4 of speaker wire
Hillbilly Antenna for your Digital TV, Priceless :-) Enjoy!!
(Spray Paint as needed)
Step 8: Results
As promised here are some results from INDOOR use of my antenna.
At my Home I was able to get all but one of the "Strong" Signals, None of the Weak. Almost all the channels have -2 and some have -3, but they are the same signal as the -1's
I got the signal information from here http://www.fcc.gov/mb/engineering/maps/, just enter your ZipCode
Signal Strengths As reported by my Tivax STB-T8
2-1 : 100 %
4-1 : 100 %
7-1 : 100 %
20-1: 30-60 %
38-1: No Signal
50-1: 100 %
56-1: ~55 %
62-1: ~60 %
The Rural Area I was able to test my results against a Philips Magnavox Antenna to see if there was a noticeable difference.
CANtenna:
9-1 : 70-100 %
Philips:
9-1 : <50 % (I had to fuss with it quite a bit)
If I brought this to the roof I may have had better results. Also an addition might be to make two of these and connect them in parallel and configure them one on top of another 90 degrees out of phase, so you don't have to adjust for different sources of the signals.
Hope this helps.
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36 Comments
13 years ago on Introduction
It bothers me to a degree that a soda can picks up these frequencies so well. I wonder how it might affect our food?
Reply 13 years ago on Introduction
Food??? I hope you're joking, right? Break out the foil hats... No differently than any other RF signal that has ever been transmitted. We're not talking microwaves here. Even that has been broadcast for decades and occurs naturally.
Reply 13 years ago on Introduction
No no no, its not the radio waves that bother me, its the fact that a soda can picks it up so well.
Reply 7 years ago on Introduction
well it is the 4th highest electrical conductor out there
Reply 13 years ago on Introduction
I guess just to be safe you shouldn't drink from any 2/3 aluminum cans.
Reply 13 years ago on Introduction
LMAO ROTFLMFAO!!!!
Priceless! love it man!
Reply 13 years ago on Introduction
Anyone read; http://www.popsci.com/science/article/2010-02/disconnected?page=3
The Man Who Was Allergic to Radio Waves
I thougt, 'BS' when I first saw the article but after reading it it raises a few questions...Reply 13 years ago on Introduction
"No way to prove"? Just put your cell on Silent and get a call without answering it-if he passes out, that's proof. If he doesn't, that's proof as well.
Reply 7 years ago on Introduction
What do you think the underground electrical wire is made out of??? Aluminum. Copper and Aluminum are the two top conductors used in conducting electricity. I'd be more worried about plastic bottles than aluminum cans.
8 years ago on Introduction
I have a digital TV but the screen is broken,is there anyway I can use the parts to make my own analog to digital box?Anybody?
12 years ago on Introduction
don´t work, thanks whether, but this idea no catch any signal in this region. Grettings from Mexico City
Reply 9 years ago on Introduction
ok theres yr problem there the only big transmitters are in the populated zones of the u.s. . there are maps 4 that some where. but if yr living south of the border then uill have other ways of getting those sat signals.
12 years ago on Step 4
instead of the spearker wire and antenna connector, could i use something like this? how should i do it? thanks
Reply 11 years ago on Step 4
well, by the looks of it you are using speaker wire already. but if that is all one wire then no. (it has to be separate wires to each can) and your Coax cable will not work with the UHF or VHF signal that will be coming through the cans. you will need a two screw lead to coax converter. (im not sure on the exact name of the device so somebody please help if i am off on it) theyre able to be easily acquired at Radio shack or online. and again on the wire, it might be a bit heavy. you may as well save it for something that needs that much copper, like a subwoofer in a car or something. the speaker wire needs to only be like 20 gauge. otherwise youre just wasting conductive material.
12 years ago on Introduction
Not cutting the cans actually increases the bandwidth.
An early on the fly HAM antenna was vertical Ham antenna called the CANtenna. It was made of metal coffee cans or tin soup cans soldered end to end in a stack approximating the wavelength desired.
Prized for its increased bandwidth, it usually had short lifespans outdoors due to weather damage
12 years ago on Step 5
Just curious here . Would a piece of 3 1/2 " schedule 40 pvc pipe work? Or would that interfere with the signal?
13 years ago on Introduction
I can't deny that the author's project worked well for them at their location, BUT... My comments are for others to consider. For a somewhat tuned antenna it's the length of the elements, in this case the AL cans, that's important, not how far apart the ends are, in this design a portion of the speaker wire is functioning as part of the dipole. Cutting a section out of the can as shown here may quite impossibly reduce the functional bandwith of the antenna As the author mentioned this is a dipole antenna en.wikipedia.org/wiki/Dipole_antenna using the common 75 ohm TV coax is a much better choice than speaker wire. Place the elements close together so the coax lead to the are as short as possible, seal the open end at the antenna to avoid moisture from entering the coax. Here is a tool to help calculate element length bfn.org/~bn589/antenna.html use this en.wikipedia.org/wiki/North_American_broadcast_television_frequencies to know what frequency to enter into the calculator for your TV channels of interest. While the data gleaned from www.fcc.gov/mb/engineering/maps/ is based on a model that uses a receiving antenna at 30' doesn't mean you shouldn't try an antenna at other heights or location on the property In the end you may be one of those that broadcast DTV isn't going to work for you where you are at.
Reply 13 years ago on Introduction
Static, You make great points. and I like the Links. I did address in step 2 the reason why the 2 CANS happen to work as a "Tuned" antenna (See end of this post).
I do, however, have a question concerning this statement:
"Cutting a section out of the can as shown here may quite impossibly reduce the functional bandwith of the antenna"
What are you saying?:
1. Cutting the Cans may completely yet won't reduce the functional bandwidth
2. Cutting the Cans may Slightly reduce the functional bandwidth
3. Cutting the Cans Won't affect the functional Bandwidth at all
I am reading the statement as "Cutting a section out of the can as shown here may quite possibly reduce the functional bandwidth"
Step 2 Quote:
"UHF (Ultra High Frequency) is the frequencies that the FCC has reserved for the new Digital Television Formats to be transmitted on.
These frequencies range from 300Mhz to 3,000 MHz (3Ghz). This means the wave ranges from 10cm to 1 meter in length, making two of these aluminum cans end to end along with some 18 gauge speaker wire a perfect way to intercept these waves"
Reply 13 years ago on Introduction
I'm saying #2 Cutting the can in the MANNER shown MAY reduce the functional bandwidth Element diameter( which is reduced for a portion of the cans in this design) is a design consideration for the bandwidth of a transmitting antenna.Even though the reciprocity between a transmitting and a receiving antenna isn't %100, I have to feel why comprise something that *might* be a positive.Here the effective length of the can hasn't been change at all, the length of an antenna element, here the can determines the design frequency of an antenna. In this design there is no demarcation point separating the portion of the speaker wire functioning as part of the antenna and the portion of the speaker wire acting functioning as the lead in. No doubt the speaker wire is also acting as an antenna, and that may be beneficial in some installations or detrimental in others. I wouldn't have said anything at all if one post mentioned duplicating the project didn't work for them.
I haven't messed with a simple antenna yet because all indications and experience are pointing me to a medium or large antenna with a preamp at the antenna. For those where a simple antenna is worth the try I'd suggest a dipole cut for 470 MHz, or a dipole cut for 175 MHz if high band VHF is still being used in your area, using standard TV coax between the antenna and TV, that way you don't have worry about keeping the lead in away from metal
13 years ago on Introduction
The results are in!!! I feel that it's a fairly good substitute antenna, see the last step for my results. The PVC suggestion for Outdoor use may be your best bet, then placing it at the recommended height (30 feet above the ground) may yield better results than I had.