General Categories of Decison

Major decisions in implementing a radio control battery powered layout are (1) Transmitter, (2) Receiver, (3) sound, (4) Batteries, and (5) Charger.  In a grid power setting, these issues are normally attacked in numerical order.  But in an off-grid setting it might make a great deal of sense to attack the decision in the opposite or at least a modified order.

Charger

A factor that will reduce electrical loss in the off-grid system is to choose a charger than can be powered with DC rather than AC.  This eliminates the need for an inefficient DC/AC inverter.  Fortunately, finding a charger that can be powered with direct current is less difficult than you might think because of the large market for radio controlled battery powered cars.  In a competitive meet setting, batteries powering these cars are often recharged using automotive batteries.  Of course, there is the issue of charging batteries when the solar system is down or when visiting another layout.

Fortunately the RCS web site and Dave Goodson pointed me to what I feel is a nearly ideal solution.  The Maha MH777Plus charger is a very sophisticated battery charging and conditioning solution.  I can charge NiCad and NiMh battery packs of up to 14.4 volts.  And it can charge them using either 24 volt DC input or 120-240 volt AC input.



I ordered a unit from Thomas Distributing for $70.  I'll be testing this unit with my first battery install.

Batteries

Last fall in anticipation of getting my railroad up and running, I invested in batteries and a charger.  The purchase included three Aristocraft CRE-55610 21.5 volt Lithium battery packs along with a CRE-s 55620 Power Supply.  The power supply uses 110 AC to charge the batteries.  This combination is outside my CD power guidelines so I am selling these units on eBay.

The North Pacific Coast railroad had average track speeds in the area of 25-30 miles per hour and typical consists of 4-6 cars.  A 14.4 volt battery power source should be more than adequate for the majority of engines running on this pike.  The North Pacific Coast was a steam railroad and the vast majority of locomotives on its roster were engine/tender combinations. Because these pre-1900 engines were relatively small, tender space is more limited than with later steam road engines.  For that reason, NiMH makes the most sense as it is a non-bleeding edge battery technology that packs significant power relative to its size and weight.

Fortunately the battery powered radio control car hobby provides many options for battery packs.  I went to the supplier recommended by the AirWire Decoder manual, Onlybatterypacks.com

From them I purchased four 3500 mah Sub-C 7.2 volt packs, one pair of stick packs and one pair of block packs.  The two different size footprints will allow me to experiment with installations.  Battery packs will be wired in series to produce 14.4 volts.  They are a perfect match to the maximum capacity of the Maha units.  Assuming both the charger and the packs perform up to expectations, all installations after the battery car will use this combination.

Transmitters and Receivers

While there are a variety of manufacturers going after the radio control battery power market, the vast majority of installations discussed in the MLS forums are the offerings from Aristocraft, RCS, and AirWire.  Because they are the most commonly used systems, I limited my search to those three.  Both Aristocraft and RCS offer low end systems in addition to their premium systems.  I rejected these low end systems as lacking the sophistication I was looking for in my railroad.

Note that this is not intended to be a side by side review for all potential purchasers.  So I have avoided doing side by side comparisons of features of the various units.  That's because all of the high end systems have features well beyond those I'm likely to use in my railroad.  What's far more important to me initially is quality, documentation, and support.  As I gain experience actually operating my railroad, performance will also become an important factor.

The least expensive of the premium systems is Aristocraft with a street price of around $190 for an onboard transmitter/receiver combination and around $130 for a trackside transmitter/receiver combination.  I'll discuss these options in detail a bit later.

The Airwire 900 system offers the choice of two separate transmitters and a single receiver.  Street price of the lower end transmitter/receiver combination is around $290 and the higher end transmitter/receiver combination is around $340. 

RCS offers the greatest number of combinations.  Because their low end transmitter only offers 4 functions I didn't include it in my comparison.  On the receiver side they offer a Basic or Elite.  I only consider Elite which is offered in both a 3 amp and 6 amp version.  With the 24 function transmitter and the Elite recever, street prices range from $268 to $299 depending on the amperage requirement of the receiver.

Equipment Already On Hand and Equipment Considered

I already own two transmitter/receiver combinations from the above manufacturers.  As my installations progress, I'll be purchasing new systems.  The following section discusses my current equipment investment and why chose to purchase new systems from RCS.

Aristocraft

In the fall of 2007 in anticipation of my Golden Spike Ceremony, I purchased an Aristocraft (Crest) CRE-55470 Walkaround Transmitter/Receiver.  The most common use of the receiver is to provide track voltage to engines running on the track, but under radio control.  Because I own an Aristocraft switching power supply, I had planned to open my railroad using track power.  At roughly $130 it seemed like a reasonable investment.



Many owners of this combination have installed the receiver in a battery car and powered it with batteries.  While the unit is bulky, a boxcar can absorb its bulk along with the battery packs needed to supply power.  Once I was ready to convert from track to battery power, I was planning to do the same.

Unfortunately I was unable to get the transmitter to sync with the receiver.  As a result, my Golden Spike day was static rather than dynamic.  I called the Aristo support line today.  They asked me to return the unit for service.  Assuming the problem is resolved, I will use it as a battery car transmitter/receiver combination powered by the Aristo batteries and charger mentioned earlier in this post.   It will be the least expensive of my initial installs especially when you consider the battery car is not intended to support sound.

In addition to the relatively new Aristo 55470, I managed to unearth two other Aristo radio control units I had purchased a while ago.  The first is a used CRE5473 receiver.  It's packaging is identical to the CRE55473 that came in the 55470 package.  So I suspect it is a version produced within a few years of the switchover from the 5473 to 55473.  It is likely my new transmitter will work with this receiver as well as the receiver it was shipped wirth.  I alao located an Aristo 5490 onboard receiver I purchased around 10 years ago.  This unit was never used.  I plan to test this receiver with my transmitter to see whether it is operational.

One of the reasons the Aristo systems are so cheap is they are produced in large quantities in large production runs.  That means Aristo products flood the market when the production runs occur, disappear when the run sells out, are unavailable for fairly long time periods (a year or more is not uncommon), then reappear some time later.  This works OK with engines and rolling stock.  But it is not a desirable attribute when you are installing radio control in your railroad as you never know when the parts you need will be available.  A second problem with Aristo can be quality control.  My unit is an example.  But that could happen with any manufacturer.  But this new generation unit shipped with old generation instructions.  It wasn't until I visited their Web site that I found that the instructions on how to sync the units had changed.  Then mine still didn't work with the revised instructions.  The third issue is that Aristo doesn't take steps to insure backward compatability with its products as generations change.

I still work for a living.  So my leisure time is precious and cash flow from earnings reduces my sensitivity to a product's price.  As a result, I'm moving forward without plans to purchase additional Aristo R/C equipment.  In my mind, the cost savings doesn't overcome the effect of the above three issues on my time.

RCS

Back on 2000 or 2001, I purchased a transmitter and receiver from one of the RCS US distributers.   The Transmitter is a TX-8, an eight function transmitter.  The Receiver/Throttle is a MT8-HV.  Neither unit is currently produced by RCS, having been supplanted with revised units with higher capacity.  These units have never been used as my partially constructed railroad was taken back up in 2001 because of a move to a new residence.  The purchase of the Maha Charger and the battery packs at 14.4 volts in series should be fully compatible with the power specifications of this older RCS equipment.  I'll assume these units are still functional.  It is my intention to do my first tender install using this equipment.

RCS currently produces TX-4 and TX-24 transmitters.  Because I want to provide provision for sound, I only considered the TX-24 in my list of potential equipment.  With the additional cost over the TX-4 being only $20, the additional flexibility of the TX-24 is worth the slight increment in price.  On the receiver/throttle side, RCS offers the Elite-3, the Elite-3HV and the Elite-6.  The HV allows higher voltage inputs.  The Elite-6 is a six amp as opposed to a 3 amp unit.  The $40 price difference between the Elite-3 and Elite-6 units is significant.  If purchasing from RCS, I would be inclined to use the Elite-6 only with locomotives requiring significant current draw.

As opposed to Aristocraft, RCS is continuously producing product, provides backward compatabilty when upgrading equipment, and has a reputation for outstanding service through its US distributers.  In my book, these three advantages offset RCS's higher street price relative to Aristocraft.

Airwire 900

Unlike the two previous systems, which are proprietary, the Airwire 900 is NMRA DCC compliant.  This means equipment from the Airwire product line can be mixed with appropriate equipment from other DCC manufacturers.  Airwire offers two transmitters, the RF1300, and the T9000.  The T9000 offers LCD display and a number of other features not offered on the RF1300.  But it comes at an additional cost of $50.  The Airwire receiver/decoder is the AW9D10SS.

As compared to the Aristo and RCS product families, my impression is that the Airwire series is the most flexible and most powerful of the three product families.  My impression from reading the documentation is they provide the best documentation, although the RCS documentation is close.  But Airwire is the most expensive solution.  I have no experience with their customer support.

The one very large Airwire negative in my setting has been discussed in a number of posts at the MLS Web site.  Locomotives using the Airwire transmitter/receiver combination have difficulty dealing with grades.  Given that my pike is built on the side of a hill with a 4% ruling grade, this is a show stopper for Airwire.  Apparently RCS and Aristocraft don't have this problem.

Of course with Airwire being DCC compliant, it is possible I could opt for a different receiver/decoder combination.  I have seen posts suggesting the QSI receiver solves the Airwire problem with grades.  It is possible I will consider Airwire at some point in the future should I have additional feedback along these lines.  But right now, I want to go with something that I'm sure will work.

Sound

All three of the above manufacturers support multiple sound options.  I would like to have the option of sound in my higher end engines (NPC prototype 4-4-0 bashes, Mason Bogies, 2-6-0 bashes, etc.)  But I don't see sound in the battery car for smaller, less prototypical engines as these engines sounds would vary.

Of the sound options, I'm currently leaning toward the Phoenix P5 system.  It's a bit pricey at $170 but where I do use sound, I want it to be high quality.  And given sound draws power and power is a scarce commodity in an off-grid power situation, I lean toward one or two engines delivering high quality sound as opposed to more engines at a lower sound quality.  I have yet to investigate the power drain brought on by adding various sound cards, so my thoughts in this area may change as investigation continues.

Short-Range Plan

It makes the most sense to take on the easiest installs first on non-crucial engines, then use experience gained from the first installs to progress toward more crucial engines.

(1) Based on what I've read, battery car installs are the easiest to take on initially.  I plan to use one of the Aristo (5)5473 walk around unit for this install in an Aristo Classic wood box car.  This battery car will contain the receiver/decoder, batteries and assorted equipment.  Batteries will be charged through an open box car door.  It is my intention to use 14.4 volts of battery power using two of my new packs wired in series.  They will be positioned allowing removal and swapping through the door should very long runs be desired.  Leads will feed the engine with motor power and lighting.  Initially, I'll set up my Aristo 0-4-0 switcher for this battery car.
(2) Assuming both walk around units work, the second install will be in my best generic Bachmann Big Hauler.  It has the largest tender and with a little fiddling, should accommodate an Aristo walk around unit circuit board.  If both receivers are operational, I'll pick up a second Aristo transmitter.  When these two are finished, I'll have my two grandkid setups.
(3) The third install will use the RCS TX-8 transmitter and MT8-HV receiver/decoder.  This will be an engine/tender install on an unlettered Bachmann 2-6-0 Spectrum that has also never been run.  The 2-6-0's engine and tender are nearly identical to my bashed NPC No 3, a Bachmann 4-4-0 Spectrum which is the only NPC bashed engine in my roster.  I want to do No 3 with my first new radio control system purchase and the 2-6-0 install would be good practice.
(4) Assuming both the Aristo 5490 onboard and the Aristo 5473 units are operational, this will be an engine/tender install on my Bachmann Annie.  If the Aristo units are not both operational, this installation will be skipped.
(5)  My fifth install will be using a new RCS TX-24 and an Elite-3 or Elite-6.  The target engine will be NPC No 3, a Bachmann Spectrum 4-4-0.  This will be an engine/tender install and will include Phoenix sound.  I've been vacillating on this install as to whether to have the install done professionally or do it myself.  Price will be a factor and I'm waiting for a quote from Dave Goodson.  I may defer the professional installation question until after I've completed my first few installs.

Long-Range Plan

I would like to select a radio control manufacturer and stay with that manufacturer over the long haul.  At this point, my choice is RCS, but that decision could change based on my experience with the above installs and how the two systems in my posession (Aristo and RCS) work out in the real (unreal) world of my garden railroad.

As I proceed with my installs, each will be posted in a separate post, under this child Web.