HO scale model trains are 1/87 the size of real trains and 1/2 the size of O scale model trains (HO stands for "half O"). As with O scale trains, the letter "O" in HO is a misnomer since the designation was initially conceived as a zero to identify trains that were smaller in scale than 1. But the use of the letter O rather than the numeral 0 crept into everyday speech among model-train buffs and remains the standard way to refer to HO scale today.

Though first invented in the 1930s, HO scale model trains didn’t become popular in the U.S. and Europe until the 1950s when the scale was heavily promoted by Märklin, Lionel, Athearn, and others. HO never quite gained acceptance in England, though, where larger 00 scale trains still predominate.

HO has two important benefits over trains of larger sizes. First, an HO scale layout of reasonably ambitious detail and complexity can fit on a table rather than requiring an entire room, as is the case with larger scales. Second, HO trains are less expensive to manufacture than OO, O, and other large-scale trains, which makes them more affordable to collectors and enthusiasts alike.

Most HO scale trains run on two-rail tracks using direct current (DC). Adjusting the voltage delivered to the tracks can increase or decrease the speed of the trains; reversing the polarity causes the trains to roll in reverse. Some manufacturers, notably Märklin, produce HO scale trains that operate on alternating current (AC), which is delivered to the train via a conductive third rail.

The gauge used by the majority of HO scale model trains is a standard HO gauge track that’s roughly proportional to the size of the trains running on top of it. But as with the OO scale trains in England that run on HO gauge tracks, HO scale trains are also made to run on a variety of different gauge tracks, which themselves are scaled-down versions of historical railroad track sizes.

Of these variants, the most common is called HOn3. This code denotes an HO scale train running on a track similar to the 3-foot, narrow gauge tracks used by Rocky Mountain railroad operators in the late 19th century.

One of the most enjoyable aspects of HO for collectors is the opportunity to join a local module club. Members of such clubs build modules of predetermined size; each module has a finite length of track. When members get together at model train exhibitions or in private homes, the modules are linked up and trains are run on the resulting massive layout, which often feels like more than just the sum of its parts.

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Recent News: HO Scale Model Trains

Source: Google News

East Contra Costa Datelines
Contra Costa Times, September 16th

Black Diamond Lines Model Railroad Train Show: 10 a.m.-5 p.m. Oct. 25-26; Nov. 1-2, 425 Fulton Shipyard Road. An operating HO-scale model train layout. Selling surplus model trains, model buildings, books, magazines, memorabilia and more. Adults $3 ...Read more

Senior News: Sept. 15 — Sept. 21
Milford Mirror, September 14th

Call for information on other tours including Colorado Rockies and Train Tour Sept. 5-13; Spain and Portugal River Cruise Oct. 3; Reflections of Italy ... The HO scale of model railroading will be used. Donations of any model railroading equipment or...Read more

Memphis Railroad And Trolley Museum Hosts Central Station's 100th ...
The Chattanoogan, September 14th

Ongoing exhibits in the museum that are favorites for youngsters include Thomas & Friends, the 1/8" scale live steam model engine of the Illinois Central Hudson locomotive #2499, the On30 model train layout modeling "O" scale using "HO" track and the ...Read more

The Swiss Golden Pass features castles, vineyards and hot air balloons
DigiNews, September 13th

Here the course moves along a singular track through an expanse of the valley that is so vast it creates feelings of being transformed into an elaborate HO scale model train layout. Ahead are the promise of bold new dimensions of freedom that deliver...Read more

Model Train Scenery Offering Christmas Season Sales
MENAFN.COM, September 11th

The shop model railroad scenery offers a wide range of miniatures of different scales including gauge 2 figures gauge 1 figures 0 gauge figures 00 gauge figures HO scale figures TT gauge figures N gauge figures and Z gauge figures. Customers can easily ...Read more

'Model Train Figures' Providing Items For Realistic Scale Model Scenery
DigitalJournal.com, September 8th

'Model Train Figures' a renowned US based company known for making miniatures is geared up to provide items for realistic scale model scenery. The company offers a wide range of scale figures including different gauges including HO scale, N scale, ...Read more

Model Train Figures Offering New Collection Of HO Scale Figures
MENAFN.COM, September 4th

Speaking to the media a representative of Model Train Figures said “HO scale figures is the most used model figures in the world. It is very less expensive than the other scale figures but the perfect one for a model train layout.” He further added...Read more

Train Days returns to Los Altos: Museum highlights model railroading
Los Altos Town Crier, August 27th

Participants include the Live Steamers from the Bay Area Garden Railway Society (G scale); the Diablo Pacific Short Line (G scale); the Golden Gate Lionel Railroad Club (O scale); a private collector's Swiss Narrow Gauge (HO scale); Peninsula NTrak and ...Read more