The MP3car.com Store  

Welcome to the MP3Car.com forums.

You are currently viewing our boards as a guest which gives you limited access to view most discussions and access our other features. Registering will also remove advertisements. By joining our free community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join our community today!

If you have any problems with the registration process or your account login, please contact contact us.

Go Back   MP3Car.com > Mp3Car Technical > General Hardware Discussion

Reply
 
Thread Tools Display Modes
Old 06-07-2005, 11:34 PM   #1
Newbie
 
gary65536's Avatar
 
Join Date: May 2005
Location: Irvine, CA
Vehicle: 2005/Ford/Escapee
Posts: 3
My Photos: (0)
Smile Car Antenna for TV

Hi, I have a DWW-700M monitor that features a built in TV tuner. From mainly an experimental point of view I'd like to try out the TV tuner but don't have a suitable antenna. I've researched around these forums and it seems that it is possible to pick up a limited signal from the car's factory antenna.

What would be a good way to connect the antenna to the monitor? As far as I can tell my car antenna has a standard (Motorola?) radio antenna plug and the monitor has a standard UHF socket (like what TVs have on the back of them). I've tried looking for a suitable adapater but have not found anything yet.

If anyone has any good ideas or knows of such an apapter please let me know.

--Gary
gary65536 is offline   Reply With Quote
Sponsored Links
Old 06-08-2005, 03:23 AM   #2
Constant Bitrate
 
Join Date: Mar 2004
Location: California
Vehicle: 2001/Audi/A4
Posts: 135
My Photos: (0)
gary,

While it seems you're trying to use the stock car antenna to improve your over-the-air television signal, you might be wise to consider installing an additional antenna instead.

While it may be true that the stock antenna can help in picking up a few signals, the antenna is tuned for AM/FM radio usage and will not help with most of the TV channel frequencies. Let me explain:

AM radio (Amplitude Modulated) carrier frequencies are in the 535-1605 kHz frequencies and is considered a fairly low band. FM radio however is smack dab in the middle of the VHF TV chunks. VHF TV channels 2 through 6 are before the FM radio channels, and VHF channels 7 through 13 follow it but are in the 174 to 216 MHz range. The real chunk of television channels (14 through 83) sit on UHF between 470 and 890Mhz. They are much further away from the FM radio frequencies and even further than the AM freqs than the first two chunks of channels which sit in the VHF bands.

So, as you can tell, you'll definately get improvement on TV channels 2 through 6, but 7 through 13 seem much more unlikely since the AM/FM antenna in the car is not tuned for 174-216Mhz, and almost 100% doubtful it will help for channel 14 through 83 since they're in the ultra high frequency band.

Really, you should consider getting a vehicular antenna that is rated for wideband use (meaning, it covers a wide range of transmission bands). There are several antennas that can cover as low as 50kHz all the way up to 1.2Ghz in one antenna. I'm certainly not an antenna wiz, I'm still learning. But having a dedicated antenna will extend your range incredibly as well, so you won't have to worry about the heavy interferance that is common with TV over the air.

I have even seen antennas that can be mounted inside your trunk sideways that will help, but they're not as functional since they aren't vertical, and they are closer to the ground.

Let me know if there's more I can help with if you choose to get a dedicated antenna. Antennas can certainly get expensive, but you should be able to find a really good one for somewhere between $50-100, and yes, cheaper ones exist, especially ones made by hobbyists. I just picked up a homemade antenna from Ham Radio Outlet that is two antennas inside a PVC pipe that I use indoors or outdoors whenever I need portability (not for car use, it's like 4-5 feet long) and it only cost me $20. Really improved my wideband receiver abilities. I recently heard a station transmitting from over 300 miles away! So as you can see, the antenna is one of the most important pieces of the puzzle, even though it only looks like a long piece of wire.

Good luck!

Kevin
__________________
Kevin
Audi A4 Carputer, 80% setup.
kevlar is offline   Reply With Quote
Old 10-20-2006, 06:34 PM   #3
Newbie
 
Join Date: Oct 2006
Posts: 1
My Photos: (0)
The real problem with car antennas and tv's

The main thing that causes a problem with tv reception over a car antenna is circuit impedance. Cars use a 50 ohm coax on the antenna and the coax circuit impedance for a tv is 75 ohm. Mismatched circuit impedance kills signal strength. That is the reason that there is a matching transformer used to connect tv coax to an off-air tv antenna that you mount outside. The antenna circuit impedence is 300 ohms and the coax, again, is 75 ohms. The trick to getting decent reception over a car antenna is finding a suitable matching transformer to match the two up. Be watching http://www.discountmobilevideo.com/. They are supposed to be in the process of producing a matching transformer splitter combo.

Donnie
DWATSON is offline   Reply With Quote
Old 10-22-2006, 03:04 AM   #4
FLAC
 
FC3S's Avatar
 
Join Date: Jul 2006
Location: Seoul, Korea
Posts: 1,025
My Photos: (0)
this thread was over a year old..
FC3S is offline   Reply With Quote
Old 10-22-2006, 04:04 AM   #5
cheap custom title
JC-S60's CarPC Specs
 
JC-S60's Avatar
 
Join Date: Mar 2004
Location: Ghent - Belgium
Vehicle: 01 Renault Espace BiFuel | Mitsubishi Canter | BMW R1200GS Adventure | Yamaha YZF600R | Honda CB650
Posts: 1,854
My Photos: (0)
Quote: Originally Posted by FC3S View Post
this thread was over a year old..

It could still help others AND a very good first post, helping instead of asking for help!

JC-S60 is offline   Reply With Quote
Sponsored Links
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
What's your dream car? Aaron Cake Off Topic 172 10-02-2007 07:34 AM
power problems while car is running.. TimW General Hardware Discussion 28 03-18-2006 09:11 PM
Someone stole your car? Try this on for size... sdashiki Hardware Development 11 04-25-2005 11:11 PM
Car Cell Antenna questions DaViper General MP3Car Discussion 2 03-14-2005 11:22 PM
S.M.A.R.T. car link138 Newbie 17 11-12-2004 09:14 AM


All times are GMT -5. The time now is 01:23 AM.


Sponsored Links
The MP3car.com Store

Powered by vBulletin® Version 3.6.8
Copyright ©2000 - 2008, Jelsoft Enterprises Ltd.
SEO by vBSEO 3.1.0
Copyright © 1999 - 2008 Mp3Car.com Inc.
Ad Management by RedTyger
Message Board Statistics