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InterMountain HO scale FP7 road diesel locomotive

Reviewed in the February 2007 issue
InterMountain HO FP7 road diesel locomotive
InterMountain HO FP7 road diesel locomotive
Here's a great-looking and smooth-running FP7 road diesel that's useful for both freight and passenger service. Manufactured by InterMountain, this interesting addition to the HO F-unit fleet is offered ready-to-run with QSI Quantum dual-mode sound and Digital Command Control(DCC)or in DC-only versions.

Dual-service prototype. The Electro-Motive Division (EMD) built 372 FP7 A units for 31 railroads between June 1949 and December 1953. Mechanically, the FP7 A units were stretched versions of the F7 freight locomotive. The extra four feet of space between the cab and the diesel engine held three water tanks that supplied the steam generator for passenger service.

These road locomotives were geared for top speeds between 65 and 89 mph so they could haul freight trains or race across the country at passenger speeds.
The steam generator details are mounted on the rear roof hatch of the FP7 A units and F7B units.
The model. Prototype plans of the FP7 were published in the Model Railroader Cyclopedia: Vol. 2, Diesel Locomotives (Kalmbach Publishing Co.). Both versions of the model FP7 closely match these drawings.

InterMountain's HO FP7 model also shares many of its features with the firm's previously released F7. It has a well-detailed plastic body shell that's made in two versions with either the original horizontal louvers or post-1951 vertical-slit vents. Numerous details are factory-applied. The stainless-steel upper grills are thin metal etchings that allow the side trusses to show through.

We examined an ACL FP7 A unit and an SP FP7 A and F7 B consist that display typical variations. The ACL unit has a Mars signal light, a freight pilot, and full side skirting, but no dynamic brake fan. [According to InterMountain, some of the ACL models, including our sample, were assembled without steam generator details. If you purchase one without these details, contact InterMountain. - Ed.]

The SP version includes a snow-plow, a 48" dynamic brake fan, cut-away skirting, and the Mars light.

The samples are all smoothly painted in realistic colors, and the printed lettering is excellent.
The mechanism is enclosed in a heavy die-cast frame with different PC boards for the DC-only (top) and dual-mode (bottom) locomotives.
The chassis is a heavy, die-cast metal box that provides much of the unit's heft. A can motor with dual turned-brass flywheels is mounted in the middle with the printed-circuit (PC) board on top.

The EMD F trucks are acetal plastic with gearboxes that snap together. The brake cylinders and swing hangers are separate parts added to the sideframes that also include the foundry trademarks.

Concealed contacts collect current from all eight drivers, and flexible wires transfer the current to the PC board. The DC-only models have an 8-pin DCC plug.

Electronic features. The FP7 is offered with a QSI Quantum sound and control system that includes a dual-mode decoder for use on either DCC or DC layouts. There are numerous sound and control options, so it's worth taking the time to read the 22-page manual to learn about the system. Many of the sounds are activated by the DCC function keys, and most have a volume adjustment.

This model includes QSI's Quantum Analog Remote Control (QARC) capabilities. The QARC system allows the engineer to use a Quantum Engineer add-on controller to operate many of the locomotive's sound features on DC layouts.
Performance. The DC-only FP7 started on 1.5 volts at 4 scale mph and reached a maximum speed of 74.2 mph. The drawbar pull is equivalent to 58 free-rolling freight cars or 19 passenger cars on straight and level track.

On DC, the dual-mode FP7's sound started at 4 volts, but it took 9 volts for it to begin moving at 1.4 mph. It reached 79.2 mph at 12 volts.

These FP7s are good-looking models with excellent performance. Given their 58-car drawbar pull, these dual-service locomotives are certainly capable of hauling a long streamliner or a hot manifest freight.
HO FP7 dual-service deisel

Prices: FP7 A unit with dual-mode DCC and QSI Quantum sound system, $199.95; matching F7B, $164.95 to $169.95 each; DC-only FP7 A, $129.95, matching B, $94.95

InterMountain Ry. Co.
P.O. Box 839
Longmont, CO 80502
Plastic and metal ready-to-run
diesel locomotive
Road names: Atlantic Coast Line, Amtrak, Canadian Pacific,
Louisville & Nashville (blue
and cream), Milwaukee Road
(yellow), Pennsylvania RR,
Reading, St. Louis South-
western, Southern Ry. (green),
Southern Pacific (two ver-
sions), Union Pacific, and
Western Pacific (passenger)
HO FP7 diesel features

Cab interior
Can motor with dual flywheels
Die-cast metal underframe
Directional headlight and lighted number boxes
Drawbar pull: 4.3 ounces
Dual-mode QSI Quantum sound and DCC system
8-wheel drive and power pickup
Etched-metal grills
Individually applied grab irons
Kadee Magne-Matic knuckle couplers (correct height)
Minimum radius: 18"
NMRA 8-pin DCC plug (DC-only)
RP-25 contour nickel-silver wheels (mounted in gauge)

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