If you R/C a live steam loco do you need to use a ground radio system? Also 2.4 GHz is the best frequency to use, right?
Use the 2.4 gHz stuff. It's the same frequency band for both ground and air, so no worries there. Each receiver is specifically linked to the transmitter. It's also virtually impervious to glitching, which is quite rampant in live steam locos under the old 27 and 75mHz radios. You can get a 2-channel 2.4 gHz set for well under $100.
Later,
K
The Home of Articulated Ugliness
Ralph, in the US--prior to the advent of the 2.4 gHz spectrum for R/C--the radios were divided by frequency as to whether they were legal for use with ground-based R/C models (cars, boats, trains, etc.) or air-based models (planes, helicopters, etc.) This was done so to avoid issues of someone running an R/C car unknowingly taking over an R/C plane flying overhead. The 72 mHz spectrum was reserved for the airborne stuff, while 75 mHz spectrum was open for the grounded stuff. That's where the "ground frequency" reference comes from. It has nothing to do with sending radio waves through the ground.
The problem was that finding ground frequency (75 mHz) controllers with more than two or three channels was fairly difficult, or at least expensive. I don't know what the difference was between a 4-channel radio in the 72 mHz spectrum vs. the 75 mHz spectrum in terms of the electronics, but the price difference could be as much as double. As a result, there were a fair number of 72 mHz systems being used on ground-based models that had more than two or three functions that needed to be controlled. (Just don't take it to any kind of formal R/C club.)
The 2.4 gHz technology's "binding" receivers and transmitters renders such differentiation based on use obsolete. If you're looking for cheap R/C stuff, you can get the old 72/75 mHz stuff pretty inexpensively as folks switch over to the 2.4 gHz stuff--but there's a distinct reason people are switching over. Interference in the 72/75 mHz spectrum is nasty.
Kevin.You may not realise it but the 27 MHz band in the USA is also legal for both ground and air usage.Ralph.There are also restrictions in the UK on which frequencies can be used for air, which for ground.There are/were rules governing the use of FM in the 27 MHz band.The 2.4 GHz equipment is fantastic.I have first hand experience of the RX's actually reliably picking up the signals even when mounted in a metal box such as the dummy water tanks on live steam locos.
Best wishes,Tony Walsham (Remote Control Systems) http://www.rcs-rc.comModern technology. Old fashioned reliability.
...the 27 MHz band in the USA is also legal for both ground and air usage...
True, but it is primarily the playground of the "toy" R/C side of things, not the hobbyist side. Most hobby shops I dealt with back when I was doing this kind of R/C only carried the 72/75 mHz stuff. I used to have a 27mHz 2-channel system, but it was a British export along with the locomotive it controlled. I think there were only 6 frequencies with the 27mHz spectrum, too--done by color. It's a very crowded spectrum, and there's absolutely no way I would ever dare fly a plane with it.
What company makes the best R/C equipment?
"Best" is a subjective term.It depends on what you want to do.I find the best value for money is the low cost stuff such as E-Sky and the Exceed brand.They cost around US$50 - US$60 for a 6 channel TX and TX on 2.4 GHz. Extra RX's are less than US$20 each.A Spektrum DX5e equivalent is about US$99. Extra RX's are about US$50 each.These are one model memory systems. That is, they will only store the servo positions for one model.Spektrum makes a 10 model memory system that allows you to program in the servo settings for up to 10 different locos. Their TX and RX are about twice the price of the DX5e.Do they work any better for live steam than the low cost systems? I don't think so.
Whatever you do, do not skimp on servo quality.I recommend only ever using servos with metal gears such as the Hi-Tec HS65MG and HS85MG types.
TonyWalsham "Best" is a subjective term.
Tom Trigg
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