S-Helper Service F7

Operator's Manual

Operator's Manual

Disassembly

Follow the link to see how to disassemble the engine's trucks. The F7 A-unit is done the same way as the NW2; see this web site: How to disassemble SHS trucks.

Brian Jackson offered this advice as to how to disassemble the F7 B-unit:
He makes the assumption that you have not added the scale coupler brackets on each end. The first thing to keep in mind is that there are two springs on the back of the unit that create an automatic contact for the speaker. Sometimes they act as a unintended lever and cause the back end of the unit to hang up when attempting to remove the shell. The second, and most likely cause of the frame not wanting to come out, is that there are a few handrail stubs inside of the unit that are a touch too long, and they are creating extra resistance. The only thing to resolve that is to rock the body shell back and forth while pulling down on the fuel tank. It is best not to pull on the trucks because you could damage the brake details, but you might need to do so carefully.

Lights

Don Thompson warns to not plug DCC decoders into this engine without dealing with the headlights first. The headlights are 5-volt bulbs, and they will blow as soon as the decoder receives power (usually around 12 volts). One option is to consider replacing them with LEDs and a matching resistor. The same applies to class lights, numberboards, and Mars lights, as applicable.

Don Thompson recalls that the wiring for the MARS light is there for single-headlight models. Note that the F7 models had the MARS light at the top and the main headlight at the bottom, as per the prototype, for dual-headlight models. This was an error discovered during the SHS F3 production run and fixed for the F7 models.

Multiple-unit Operation

If you operate multiple F7 engines together in a consist ("MU"), and each have their own LocoMatic board (i.e. they could, potentially, each be operated on their own), the MU cable between the units is not to be used. If one engine is a slave (i.e. it cannot operate on its own), then the engine has to be connected with an MU cable.

The photo shown below is of the circuit board for the F7 A-unit, set up for multiple-unit operation, non-sound version (part #661-X033R3).

Couplers

How to convert the model to "scale". Don Thompson indicated that the F-units require the same steps.

Printed-circuit Boards

The next photo is of the circuit board for the F7B-unit, with DC power, non-sound version (part #661-X004R1).

This photo shows the above-mentioned circuit board installed.

This circuit board is for the F7A-unit, either AC or DC power, non-sound version (part #661-X030R2).

This circuit board is for the F7 A- and B-unit, with DC power, non-sound version (part #661-X031R4).

This photo shows the above-mentioned circuit board installed.

LocoMatic Sound

This next board is for the F7 A-unit, with LocoMatic, either AC or DC power, sound version (part #01201).

Soundtraxx Tsunami Sound

This refers only to the first-generation of Soundtraxx Tsunami DCC sound decoders; the second-generation came out much later, long after these models were sold. This document, provided by Don Thompson, contains the configuration variables (CV) settings with which the F7 models were configured when shipped from S-Helper Service. Note that at some point in the production run, these were replaced with QSI Revolution sound decoders (see below), because the F7 models could draw more amperage than what the Tsunami decoder could provide.

This is an external link to how to install a Soundtraxx DCC sound decoder.

This is the circuit board layout of the board that S-Helper Service installed in their F7 (only) models that were using the Soundtraxx Tsunami DCC decoder. This diagram shows how the various wires are to be connected. This version is for the models that have Mars lights.

Same as above, except that this version is for the models that did not have Mars lights.

The next photo is of the circuit board for the interface for the F7 where additional resistors were needed from the outputs of the Tsunami for powering S-Helper Service's 5-volt lights and LEDs. This was part #661-X002. This is for the version with the Mars lights.

This photo shows this board and the Tsunami installed in an F7. Note that the 5-volt lighting function of the QSI Revolution sound decoders (see the next section) made this interface board obsolete.

QSI Revolution Sound

This document provided by Don Thompson describes how to install the QSI Revolution sound decoders. These were used in the later runs of this engine. QSI DCC Installation Document.

TMCC Installation

This is an external link about how to do a TMCC Compatible Conversion.

Detailing and Painting PRR Units

Bill Lane wrote an article in the January 2004 issue of Mainline Modeler about how he modified the A-B-A set by adding opened front coupler doors, Pennsy nose lift rings, and additional grab irons. The PRR antenna took a bit more work. He built a brass drilling jig, so that he could properly position the stanchions for the antenna, and duplicate that effort on the other A-unit. He tested the A-B-A consist to work properly in DC (required some electrical work), before installing DCC. The article ends with how he painted the modified areas and applied weathering.