Thank you to those who provided information about the operation of
headlights and Mars lights on GP-7 and SD-7 motors. Here’s a summary of
what I learned, for those needing to program DCC decoders.
Pyle National sealed beam twin headlights were used on both motors. For
the GP-7, they were mounted below the Mars light, which was located where the
stock headlights would have been. For the SD-7, they were below the elevated
twin oscillating Mars lights. Both lenses of the Pyle lights are clear. The top
lens of the Mars light in clear and the bottom lens is red. The white Mars light
oscillated in the direction of movement and extinguished in the opposite
direction. The red Mars light lit and oscillated only when the emergency brake
was applied. The headlight dimmed in reverse, and the white Mars light turned
off. The oscillating speed of the Mars light was approximately one rotation per
0.75 to 1 second. Speed varied between locomotives due to mechanical issues.
I’m still adding details to the GP-7 and SD-7 before painting
them, so it will be a while before I get to decoder installation and programming.
Meanwhile, I’ve added a QSI Titan-U decoder to the Con Cor Mars
light Zephyr. The decoder came programmed with Winton sounds, and was plug and
play for the lights, however the lighting effects I get don’t match operation
characteristics described above. Here’s how they work now:
Front Lights (headlights and Mars Light)
Idle – headlight dim, clear Mars light dim, not oscillating, red
Mars light dim, not oscillating.
Forward – headlight bright, clear Mars light bright and
oscillating, red Mars light bright, not oscillating.
Stop from forward – headlight dim, clear Mars light dim, not oscillating,
red Mars light dim, not oscillating.
Reverse – headlight bright, clear Mars light dim, not
oscillating, red Mars light dim, not oscillating.
Stop in reverse – headlight dim, clear Mars light dim, red Mars
light dim
Rear Lights (Mars light)
Idle – clear Mars light off, red Mars light dim, not oscillating.
Forward – clear Mars light off, red Mars light bright, not
oscillating.
Stop in forward – clear Mars light off, red Mars light dim, not
oscillating.
Reverse – clear Mars light bright, not oscillating, red Mars
light off.
Stop in reverse – clear Mars light off, red Mars light dim, not
oscillating.
There seem to be some anomalies compared to GP-7 and SD-7 Mars light
operation. I don’t think the front red Mars light should ever light on
the model, unless a decoder function is programmed as a manual emergency stop. The
headlight should dim in reverse. I think the rear clear mars light should
oscillate in reverse. Does anyone know how the front and rear Mars lights
operated on the shovelnose Zephyrs? I’d like to know before reprogramming
the decoder to make the red Mars light follow prototype practice.
While the Winton sounds are recorded from a 248 instead of a 201A, they
are better than the available EMD 567 sounds recommended for the Con Cor
Zephyrs by other decoder manufacturers. The addition of two speaker stereo
sound from the Titan-U is a nice development, as now the horn, bell, fan,
motor, etc. sound can be localized in a locomotive to their actual locations.
Two speak sound is much richer, especially since there’s room in the Con
Cor models for two 1 in. speakers or a 1 in. speaker in the front and a ¾
in. speaker in the back of the powered unit. Now if I can just get the lights
working as they should, this will be a truly impressive model.
Nelson Moyer