Outrun your rear camera?

[drillagent]

So, DW and I went to the Midwest RV Show in Kansas City yesterday and stopped by a booth run by one of the local vehicle mod shops. They said they could definitely install a new Titan fuel tank in my tow vehicle, but I would have to call for pricing. While I was at it, I asked if they could install a wireless rear view camera into my 5er. The gentleman there said they could, but they prefer to install wired cameras because at highway speeds there is the tendency to "outrun the wireless signal". ???? Is that even possible? I'm no physics guru, but I thought radio waves traveled at the speed of light? Has anyone ever heard of this before or had it happen to them?

[Cummins12V98]

Rolling Retreats said they place the sending unit up near the front on the roof with a wire connecting the camera to the sending unit for better signal to the monitor.

[camperkilgore]

Here's a comparison of some camera systems which might help,
http://rear-view-cameras-review.toptenreviews.com/

[lillyputz]

All I can is LMAO.

Lilly

[drillagent]

Thanks for all the info. I think the salesman was trying to put into layman's terms the issues with wireless cameras.

That being said, I've been looking at the TadiBrothers 9" Mirror with Wireless 120° RV Backup Camera. http://www.tadibrothers.com/Catalog/BackupCameraKits/9-Mirror-with-Wireless-120-RV-Backup-Camera

I prefer to have the rear view mirror camera because I still look at the mirror out of habit, and I already have too many electronics on the dash. (GPS, TPMS, etc)

I have a real fear of drilling extra holes and tearing apart things IOT run more wires. Does anyone have experience with that system? What do you more knowledgeable folks think of it?

Thanks again for all the help.

[Water-Bug]

Radio signals (RF) are nothing more than electro-magnetic disturbances cause by placing any varying electronic signal on a piece of wire. That electronic signal generates an electro-magnetic field by conducting through the air to a ground or ground plane. That path is commonly referred to as a ground lobe. An antenna can be made directional by simply placing a ground plane in one direction. It is made omni directional by providing equal ground lobes in all directions. Land based transmitters use the earth as a ground plane, thus the term. Mobile systems use a metalic surface to simulate a ground. If it's length isn't appropriate to the frequency transmitted, it becomes an inefficient ground plane. Ideally, mobile antennas have an active antenna element with a wavelenght appropriate for the frequency transmitted and a ground plane of equal dimensions. In reality, the ground plane for mobile applications is the skin of the vehicle. It is not ideal because it is abnormal in shape and conductivity.

EDIT Since most vehicles are longer front to back than side to side, the ground plane for vehicle mounted transmitters is usually more efficient front to back than side to side, thus my initial BS comment regarding ground plane issues when transmitting from trailer to cab.

EDIT On the receiving end, that same electro-magnetic field passes through a wire (the antenna) and causes a current to flow which creates voltage that is the recieved signal. Receiving antennas are also directional because they are designed to reflect/direct the signal or to shield it from being received.

[camperkilgore]

I think we've covered the OP's questions about the problems with wireless cameras, and the dealer's preference for wired systems.

The dealer used a simple(even if it is incorrect) description of the problems with inexpensive wireless cameras, so as to promote wired cameras, which he feels more comfortable selling to a customer.

I think many people(me included) like to have as much info as they can regarding technical problems with electronic devices, so any discussion that adds to that knowledge base is welcome. Ground plane info was unknown to me before this thread, and I found it very interesting.

If extra technical info is not wanted then it would be appropriate to just allow ones eyes to glaze over and say "uh-huh".

[Water-Bug]

The whole ground plane discussion is rediculous. The comparison of cheap camera transmitters to multimillion dollar satillite GPS and satellite TV transmitter systems is also rediculous. To be fair, a comparison to wifi or bluetooth is more realistic. They both have the same supposed groundplane issues and perform very well at distances of 50 feet.

[neal10a]

camperkilgore wrote:
Good info in this thread. Ground plane and polarization of antennas theory is very interesting and gets into the nittygritty of rf electrical engineering.

But it's not usually found in the advertisements for even quality cameras, and for most laymen it's really not a "need to know".

The main thing to look for in a wireless camera is interference elimination in the design and reliability, both of which are found in WIRED camera systems. More difficult to install, but if you count on seeing that car behind you changing lanes and possibly presenting a hazard, then the wired system is for you. It's not to say that wired systems are totally reliable, because there's always the connection at the tow vehicle that can become intermittent. But that connection is easily repaired.

I have a wired camera, and I have been tempted to get a wireless one, but I still come back to the reliability quotient of the wired camera.

You make a good point, but when the OP asks a question, the answer sometimes requires a technical answer. Out running an RF signal is no where accurate and is very misleading. Wireless cameras and tire monitors have restriction on the power output and therefore are influenced by things that are normally insignificant, but present in other more powerful RF signals that we are accustomed to. You are right about quality and the more expensive devices have the quality of engineering to minimize the extraneous influences of RF signals. In other words, less expensive units that have the same power output as expensive units do not perform as well. Digital units have an edge over analog units and cost more because they have more engineering to minimize problems.

[camperkilgore]

Good info in this thread. Ground plane and polarization of antennas theory is very interesting and gets into the nittygritty of rf electrical engineering.

But it's not usually found in the advertisements for even quality cameras, and for most laymen it's really not a "need to know".

The main thing to look for in a wireless camera is interference elimination in the design and reliability, both of which are found in WIRED camera systems. More difficult to install, but if you count on seeing that car behind you changing lanes and possibly presenting a hazard, then the wired system is for you. It's not to say that wired systems are totally reliable, because there's always the connection at the tow vehicle that can become intermittent. But that connection is easily repaired.

I have a wired camera, and I have been tempted to get a wireless one, but I still come back to the reliability quotient of the wired camera.

[BulldawgFan]

Water-Bug wrote:
Me thinks the comment was tongue in cheek.

EDIT. Actually, I have to put my TV in reverse to activate the rear view camera. It is a little rough on the tranny at highway speeds. There is an after market camera controller available that is a heck of a lot cheaper than a new tranny. Since I rarely back up at highway speeds, I haven't bothered to get one.

Bingo! Glad you got my sense of humor.

[Water-Bug]

Me thinks the comment was tongue in cheek.

EDIT. Actually, I have to put my TV in reverse to activate the rear view camera. It is a little rough on the tranny at highway speeds. There is an after market camera controller available that is a heck of a lot cheaper than a new tranny. Since I rarely back up at highway speeds, I haven't bothered to get one.

[neal10a]

BulldawgFan wrote:
I still just trying to figure out why he wants to back up at highway speeds?

They are also handy as rear view cameras. I use it to make sure my bicycles are ok while traveling as well.

[BulldawgFan]

I still just trying to figure out why he wants to back up at highway speeds?

[neal10a]

justme wrote:

Dennyha wrote:
I bought and installed a Voyager WVOS511 Wireless backup camera. I wasn't happy about the price, but I am happy about the performance.

I agree, but mine does wag out while traveling with my 40 ft trailer and I really appreciate the explanations of Neal10a..... He obviously has a good grasp of RF.

Thankyou Justme for the kind word. One of the reasons the voyager cost more is because of the type of modulation and pairing technology it uses that makes it relatively immune to other RF signals and interference. However it is susceptible to signal loss/interference for the reasons I previously mentioned. The GPS and in-motion satellite TV are relative immune to signal loss/interference because of the signal modulation and sophisticated detection they use. Also Satellite TV uses a very directional dish antenna that significantly eliminates multipath/interference signal problems. GPS receiver antenna is omni-directional uses a very sophisticated algorithms to sort out a very weak signal that aids its ability to reject unwanted signals.
Subjects like this are very difficult to explain and leave a lot of room for mis-understaning and pet beliefs.