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Discussion Starter #1
I'm a year away from actually acting on my plans for some outdoor railroading (guess why I don't call it "Garden" Railroading). At this point, I'm leaning toward Aristocraft units, brass rail, battery power and CSS remote control. Not sure about sound at this point.

I've read comments about the distance that CSS is effective for. Since I plan to, at least eventually, have a mainline running most of the way around my 3/4 acre homestead with main operator station at the (rail)yard at the rear of the house, I expect I'll lose control of an engine that's passing by the front of the house.

Thus, my question: has anyone tried an external antenna to get extra range from the unit? As a licensed amateur radio operator (here come the HAM jokes) I have lots of experience installing antennas on rooftops. That sounds like a good solution to the problem, at least for me.

I realize that's a year or two down the road, but I'm trying to plan for the "big picture".

Comments would be appreciated. Guffaws accepted.

jack
 

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Jack,
I have no knowledge to share on this topic, but would be highly interested in any possibilities.
JimC.
 

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CSS?

Range has mostly to do with how you arrange the receiver antenna. When I put a 27Mhz receiver in the boiler of my mallet to operate the sound, I ran the antenna along the inside of the boiler top. Had to lay the transmitter on the steam dome to work it:eek: Next time I had it apart, I wound the antenna wire around a piece of card and taped it to the backhead. Now it works from quite a ways away.

You're a ham! You know more about antennae than me:D
 

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Jack, are you possibly meaning CVP? All I can find on CSS is Cascading Style Sheets (web site programming) and Corporate Safe Specialists who do have a remote control safe.

The antenna situations are same as typical ham stuff, you get duckies for the 900 MHz stuff, and long wire for the 27 MHz stuff. Ground planes seem to be pretty ineffective, even though you have the rails (probably since not a good radial pattern).

73 de N6RGZ
 

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I'm not sure what css is either. My experience with RC is far more limited than most people here and I have a smallish layout but so far I can find no rhyme nor reason to range. I have mostly the aristo 75 mhz system and I've tried all sorts of things to mess with range--extending the antenna, wrapping it over external handrails, installing motot noise suppressing chokes, using a "black kat" antenna, and it seems pretty random to me. I have one aristo loco with the antenna soldered to the track leads one with the antenna stretched out under the boiler shell, and they seem about the same. I have a usa trains loco where I just stuck the antenna inside the cab in a jumble and it gets excellent range. I have three old LGB engines and they all seem to get the same range even though the antennas are in different configurations. Probably the best in in this little engine, where I took the antenna and coiled it around a plastic tube and hot glued it to the coal bunker



But it still seems only slightly different and it to vary with the orientation of the TX antenna or the position of my hand of sunspot activity or the phases of the moon or the stock market.

I have one airwire tx/rx and it seems to get less eccentric range variations. It's got good range and seems more consistent
 

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Discussion Starter #7
Sorry I added to the confusion. I meant RCS, not CCS or CSS or whatever else I may have typed in.

Since my plan is for a long-distance railroad that circles the house, a roof antenna would eliminate the house as signal-blocker so I can maintain control of a train at the other end of the area. I also hope to install a color TV transmitter in the engineer's seat and I'll need a central receiving antenna because the transmitter is only good for about 300 feet of open space. My amateur radio license would allow me to add a power amp, but improving reception of the weak signal would be preferred.

I'm thinking that the 27 mHz R/C units could have their range extended by swapping the whip antenna with an antenna on the roof. I'd be willing to bet that a simple CB antenna on the roof would offer a fair increase (CB band is on 29mHz: close, but a bit inefficient). Presuming the whip antenna is removeable from the xmtr unit, you'd only need to wire a similar connector to the CB antenna strapped to your chimney. (Roof work is dangerous; do so at your own risk.) Easiest would be a simple wire dipole which could be strung horizontally between two trees, or chimney and a tree, etc.

Here's a link to instructions to build a simple wire dipole, courtesy of the ARRL (American Radio Relay League) website: http://www.arrl.org/tis/info/pdf/9304064.pdf

If you decide to look at it, notice the dimensions for the "10-meter band". That's 28 mHz, right between CB and your R/C! Close enough.

jack
 

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It will be virtully impossible to achieve good range if other types of RF transmitters such as colour TV cameras are installed inside a loco along with on board battery R/C and the batteries.
Sound systems may also restrict range somewhat.

No matter what brand or type of R/C equipment you intend to use, the easiest way of achieving the maximum range possible is to have the batteries and R/C equipment all mounted in a trail car of some description.
The receiver part should be mounted up in the roof of the trail car as high as possible with the antenna stretched out around the perimeter of the roof.
Doing this keeps the R/C receiver as far away as possible from any motor "noise" interference and magnetic fields.
Depending on what type of ON - OFF switch and charge jack you install you will likely also need to add RF chokes to suppress that motor "noise".
If you choose to use an RCS trail car installation kit the RF chokes are built in.

The longest range of all, when compared to any proprietary brand of R/C such as RCS, TE, Locolinc and CVP, will be achieved by using a regular Digital Proportional R/C such as made by Futaba and Hi-Tec, married to my EVOLUTION R/C ESC's.
 

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A small point, you will probably be violating FCC law by putting a higher gain antenna on the transmitter. Anything that transmits must be FCC approved, and the output power is a combination of the electronics and the antenna. You probably won't be having the FCC bang on your door, but you could possibly cause interference to your neighbors.

Just a small point, most likely nothing will happen.

Regards, Gerg
 

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Greg,
Just to be pedantic.
Not everything transmitting requires FCC approval to be sold in the USA.

On the 27 Mhz band, provide the transmitter output is crystal controlled and below the specified maximum power output, under FCC rule 95603b, formal FCC approval is not required.

As an aside.
I would be delighted if Jack could show me how to increase the power of the RCS TX-24 as it does not have a whip antenna that could be replaced by an antenna on the house roof?????
 

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Actually, it is approved as long as it radiates under a certain power output. Adding a higher gain antenna could cause it to radiate over that limit, and thus become illegal. Remember it's the radiated power, not the power at the antenna connector. Take a look at that rule, I'll bet you it says radiated power.

Regards, Greg
 

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Discussion Starter #12
I take a drive for a few hours to visit a new G layout and have much mail to respond to. Hmmmm....

I didn't want to be too specific lest it be perceived that I'm trying to advertise a product I sell (a little sideline of mine). My TV camera/xmtr transmits on 434 mHz (cable channel 59). Its signal is normally good for 3-400 feet in an open area; picture starts to get snowy around 300 ft. 434 mHz is in the amateur 440 band, so I, as a licensed operator, am allowed to use a power amp if necessary to get the job done. For the non-licensed user the unboosted unit is in that grey area of "too weak for anyone to care". Power amp would NOT be a good idea.

Re: signal strength, different situations have different rules. Most transmitting devices, when outputting within their authorized limits (whether licensed amateurs or laymen), can use any type of antenna: beams, yagis, dipoles, etc. This is sometimes confused with broadcast stations who are licensed for very clearly defined power output and directionality in order to "protect" a neighboring station on the same or adjacent frequency. This is "ERP", effective radiated power. I happen to be the Chief Operator (not Chief Engineer) of a non-commercial station that uses an 11,000 watt transmitter and three-bay antenna to put out 5000 watts between SouthEast and South of our tower, and 15000 watts the rest of the compass. Be glad you don't have to deal with that stuff.

Beyond all that, I do apprecaite your comments since I have yet to invest anything except thought into Garden Railroading. I'm gradually learning about the hobby to the point that I may break ground next summer, although I may take the plunge this winter and buy an RDC and install TV in it and try it out on a friend's layout next Spring. Your comments help me avoid re-inventing the wheel.

jack
 

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It’s amazing how 4 inches in antenna height can affect radio range. My FA-1 has a Black Kat antenna mounted above a 75 MHz receiver.



This, along with the usual compliment of chokes, capacitors and a telescoping transmitter antenna, will give me reliable and responsive radio range of at least 135 feet.

While working on the FA-1, I set my engine cradle on the ground with the engine in it upside down. The radio range was a dismal 10 to 15 feet. I flipped the engine over, set it on a test stand and radio range was instantly restored.

Tony’s comment above lifting the receiver is interesting as I plan to build another Evans power car. Ordinarily I would mount the receiver on the floor of the boxcar and bend the Azarr M-27-L Micro Lite antenna to fit under the roof.



Perhaps it would be better to mount both as close to the roof line as possible. However I do have a concern about the high center of gravity.

Here are a couple of hard lessons learned over the years that are worth repeating for those looking for better radio range.

1. If you intend to use the 75 MHz receiver on-board a locomotive, not in a trailing power car or B unit or tender, radio noise will interfere with receiver’s reception and limit its ability to slow the locomotive down. RCS sell a small circuit board (RK-CHK) that provides the proper radio noise suppression components to overcome this problem.



If you want to read more, there is an article in the MLS archives about
Radio Noise Suppression.

2. The Azarr Antennas, Black Kat for 75 MHz receivers and M-27-L Micro Lite for 27 MHz receivers, are inexpensive but an excellent way to obtain good radio range. Both are small and much easier to install than metre/yard long wires.

3. A telescoping antenna on a transmitter will dramatically increase radio range. I recently sold Dougald my RS-3 and we attempted to run it using his new transmitter which had the infamous short rubber antenna. Range was a dismal 10 to 15 feet. I removed the antenna and replaced it with a 3 foot length of light wire with a washer on the end. Radio range jumped to 75 feet. When that was later replaced with a telescoping antenna, range of 135 feet (the length of his railway) was reliable and responsive.
 

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Discussion Starter #14
An excellent and helpful summary, Paul; trualy, #3 should be plenty for most situations.

I made a rudimentary map of my lot today to get a better feel for the distances and obstacles involved. The back yard is easy, about 100 hundred feet from patio to farthest the mainline is likely to go. Good, so far. But the mainline running around to the front of the house could be, from the patio operating position, 75 feet as the crow flies (through the house!). For the sake of dependable communication, I suspect I'll be strapping a six-foot vertical to the chimney.

jack

Let's see....A square + B square = C square.
 

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Hi Paul.

Jack was referring specifically to increasing the range of RCS. I use a separate receiver which makes it very simple to raise up high.

Jack.

Whilst I certainly agree that a longish extending section antenna would certainly improve the range of RCS, unfortunately it is not possible to fit one to the RCS TX handpiece. There just isn't room in the TX handpiece case.
Also, mounting a long "poke your eye out" antenna on the RCS TX would kind of defeat the purpose of having the smallest TX on the market.
When RCS is properly installed, the range will be more than adequate given the layout dimensions quoted.

I have no idea how mounting an antenna on the roof of the house would benefit on board battery powered locos.
 

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Discussion Starter #16
Tony -

Maybe it's because I grew up in the days of AM radio. Your car goes under a bridge and you momentarily lose the radio station. I work in a one-story building where most cell phones can't connect with the outside world. I've been dealing with a Wi-Fi company that wants to put their antennas on our tower because it's the highest spot for miles.

But if you say I can expect to have good reception 75 to 100 feet away, with the house in between, I'll gladly accept your say so. I don't really NEED another lightning rod up there.

Regards,
jack
 

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Jack,
75 - 100 feet is perfectly achievable, perhaps even with a house in between.
How do you propose seeing what the train is doing on the other side of the house?
Letting any LS locos run unattended and out of view is fraught with danger.

I still don't understand how you would expect a house mounted antenna to improve the range/reception of a hand held transmitter and an on board mounted battery R/C receiver.
 

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Putting the antenna up high is an attempt to improve the range, but that really only applies when there is something that might get in between the transmitter and the receiver... like the cuvature of the earth, or a building that has a lot of RF absorbing material in it (aluminium siding?). I can understand putting the antenna on the chimney to get the signal down around the sides of the house, but only of the train is not right against the foundation.

Another problem would be, if the transmitter only has, say 100 ft of range, and the antenna is placed on a 101 ft tower, then the signal will never reach a train on the ground. Also consider the diagonal distance from the transmitter antenna and the receiver in the train on the ground. if the base of the transmitter antenna is 99 ft from the farthest point on the railway and the antenna is 25 ft up in the air, the diagonal distance from the antenna to the train is 102.1 ft.

There is also the problem of a cable from the handheld transmitter to the antenna. Kind of defeats the purpose of a handheld. You'd need a couple hundred feet of coaxial cable so you can walk to the locomotive while still holding the controller. That miuch coax might have enough loss as to result in very little signal at the antenna end to be radiated.
 

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Discussion Starter #19
I don't recall saying anything about a 100 ft. tower. It's a single-story house. And I did refer to the various angles involved (that little postscript "A square + B square = C square).

Nor did I mention "walkaround" at all. The goal in this case, at least occasionally, would be to control the train while seated with adult beverage in hand. The TV camera/transmitter would keep the engineer informed of what's going on from the 1:29 engineer's perspective. A picture leaning to one side would surely indicate a problem that needed attention.

Curvature of the earth is not the question, it's the walls of my house that might dimish the effective signal. (FYI - the Wi-Fi company I referred to does indeed want as much height as possible even though their signal will be nowhere near the 50 mile horizon.)

Anyway, I guess we've pretty well beaten this to death. When I get up and going next summer, I'll let everyone know if I make any unexpected discoveries. I do appreciate everyone's thoughts on the matter.

jack
 

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I was talking with Dave Goodson (who has done five RCS r/c installs for me) and was commenting on the receiving distance that I was achieving. Dave told me that, when properly installed, the reception should be at least 75 ft. minimum. He also showed me that the track itself becomes an antennae. This is significant because taking a piece of wire and attaching it to one side of the track and then running it up to about 6 ft. in height will dramatically increase the distance whereby you can control all functions (as much as 150 ft.+!) The transmitter is powerful enough for the range. The trick seems to be in the reception. I was already using this technique for providing track power (which I no longer use) and noticed significant improvement in reception! No 100 ft. towers and no extra antennae! :)
 
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