ALCO PA refers to a family of A1A-A1A diesel locomotives built to haul passenger trains that were built in Schenectady, New York in the United States by a partnership of the American Locomotive Company (ALCO) and General Electric (GE) between June, 1946 and December, 1953. They were of a cab unit design, and both cab-equipped lead A unit PA and cabless booster B unit PB models were built.

Power type: Diesel-electric
Builder: Partnership of American Locomotive Company (ALCO) and General Electric (GE)
Model: PA, PB
Build date: June 1946 –December 1953
Total produced: 297
AAR wheel arr. : A1A-A1A
Gauge: 4 ft 8 1/2 in (1,435 mm)
Length: 65 ft 8 in (20.02 m)
Locomotive weight: 306,000 lb (138.8 t)
Prime mover: ALCO 244 V16
Engine type: Four-stroke diesel
Aspiration: Turbocharger
Displacement: 10,688 cu in (175.14 l)
Cylinders: V16
Cylinder size: 9 in × 101/2 in (229 mm × 267 mm)
Transmission: DC generator, DC traction motors
Top speed: 117 mph (188 km/h)
Power output: 2,000 hp (1,490 kW) — PA-1/PB-1
2,250 hp (1,680 kW) — PA-2/PB-2
Tractive effort: 51,000 lbf (226.86 kN)
Locomotive brake: Independent air.
Optional: Dynamic Train brakes Air

Sound Projects

There is 1 Sound Project for this Locomotive
PA1 8 bit project by John McMasters, added on May 9, 2013

Baseline Notching Project 3/19s/2013
Project: baseline Notch
SDF:  myNotch11 v11.14
Author:  John McMasters
 ALCO 244 V16
Power type    Diesel-electric
Builder    Partnership of American Locomotive Company (ALCO) andGeneral Electric (GE)
Model    PA, PB
Build date    June 1946 –December 1953
Total produced    297
AAR wheel arr.
4 ft 8 1/2 in (1,435 mm)
Length    65 ft 8 in (20.02 m)
Locomotive weight    306,000 lb (138.8 t)
Prime mover
ALCO 244 V16
Engine type    Four-stroke diesel
Aspiration    Turbocharger

Displacement    10,688 cu in (175.14 l)

Cylinder size
9 in × 101/2 in (229 mm × 267 mm)
Transmission    DC generator,
DC traction motors
Top speed    117 mph (188 km/h)
Power output    2,000 hp (1,490 kW) — PA-1/PB-1
2,250 hp (1,680 kW) — PA-2/PB-2
Tractive effort
51,000 lbf (226.86 kN)
Locomotive brake
Independent air. Optional:Dynamic
Train brakes

CV155    Notching mode should(must) be =1: 0 = Auto, 1 = Semi auto, 2 = Manual [1]    
    Reverse F9 off/on so auto brake is on off 2/8/2013
    Fix Deceleration cascade 2/8/2013
    Fan sounds(2) auto 1/2/2013
    Coupler slack sound 1/2/2013
     Modified references to CV156-171 by replacment with existing 12/7/2012
    F20- Disable hard auto brake 12/16/2012
     F9- Enable auto brake (off=enable, on=manual) 12/17/2012
    Removed overrev on acceleration 12/18/2012
    Added manual notch selection F21-F28
    Disable toots w/F15 on 3/5/2013
    Accelerate from idle will set run at notch 2. On timer unmoving loco will reset to idle notch 1. 3/6/2013
1) animate the sounds:
    a) automatic notch up (F11 on) when starting from stopped state.
        i) F11 will still manual notch up.
        ii) internotch transitions will still occur.
            since these are delayed by the decoder
            other animations fill the gaps.
        iii) when F11 is on the initial start from stopped
            will set notch to run2 sounds rather than idle
            Also, will rev up from 1-2 and then from 2-3 with
            load effects (more low end sound)
    b) automate notch down (F7 on) when stopped; i.e., even if higher
        notch is selected.
    c) on long duration constant running:
        i) vary the run sounds by transition from 3-2,
            2-1, run 1 (coasting), then transiton from
            1-2 and then 2-3 before resuming previously
            selected notch run sounds.
    d) on braking when moving reduce the running notch by
        -1 when F7 is on
    e) on dynamic application when moving reduce the running
        notch by -1 when F7 is on
    f) on slow to stop toot once when F3 is on
    g) on reversal toots and clash with F3 and/or F15 is
        on [F11 off + F15 off = no extra sounds]
            [F11 on + F15 on = all extra sounds]
            [F15 controls auto clash and uncouple]
            [F3 controls auto clash]
    h) optional startup sounds disable when F0 is on
    i) modified crossing sequence volume with simple doppler decrease/increase -L L +S +L
    j) distance event routine plays horn (disabled by F16 on), increases notch to 7 then back to 1
        SCV_DISTANCE_RATE (CV139) Distance Value (MUST BE 24-30). Default 24 = 2-3 min @ max speed
        F16 will disable grade crossing feature
    k) HEP option for passenger service: startup, ramp up to hep rpms
            ( F40PH ramps up to notch 7, P42 ramps up to notch 4),
            startup HEP mode sound, continuous notch speed and HEP generator sound,
            load will not change notch when in HEP mode and notch will stay constant;
    l)    Notch will reset when not moving based on timer 60-70 min
    m)    smooth transitions blend, gain, pitch on accel and decel.
    n)    release hand brake on engine startup (unless disabled by F5)
    o)    release air brakes on manual toggle F3 and on move from stopped
    p) auto brake on decelerate (two rates hard and short) with F9 off (f9 on plays manual)
    q)    project will set CV132 to 96 (between 64 and std default 127);
        Adjust for your specific motor...
    r)    F21-F28 Select Notch 1-8
NOTE: F6 and F11 have been swapped. F6 is bell and switcher
    speed (CV54=1). And F11 is notch UP.
CV settings tested:
    Since notch value (WORK_NOTCH) is set dynamically by
    the decoder certain speed table values are needed
    to let the decoder compute notches above 5.
    CV132 Notch Rate = 132 Causes notches to increas
                            logrithmetically (early)
                            See test results for notches below.
    CV154 Auto Horn = 1 (Automatic) plays highball on forward (Is Steam blowdown vol for non-diesels)
    CV155 Notch Mode = 1 (SemiAutomatic) Causes decoder to give new notch for F11 (up)
                            and F7 (down)
    CV3 Acceleration = 10 Greater values further delays notch changes and
                        subsequent transition sounds.
    CV4 Deceleration = 15 Greater values further delay notch down sounds.
    CV9 Kick Start = 0 BEMF and speed table controls starting voltage
    CV55    = 128 Makes for fast response to load changes (no pause prior to
                    application of power). See CV57 below
    CV56    = 80 Makes for fast reponse to load. When both the motor and the
                amplifier requires lots of voltage the motor will suffer.
    CV57     = 15 Enables SDH164D and other sound decoders to respond to
                speed changes without undue load on voltage supply. Therefore
                the sounds Horn and Bell will not rob supply from the motor
                causing noticeable slowing of the motor
    CV2    Start    = 7 Basic Speed control is not used for the test. If it
                were used then this value is similar to that for the
                start curve in the speed table that is used.
    CV5 Max    = 49 Basic Speed control is not used for the test. If it
                were used then this value is similar to that for the
                speed step CV78 in the speed table that is used instead.
    CV6 Min = 9 Basic Speed control is not used for the test. If it
                were used then this value is similar to that for the
                speed step CV67 in the speed table that is used instead.

    N1 1-3   *(SP read from DT402)
    N2 4-16
    N3 17-38
    N4 39-75
    N5 76-77
    N6 78-
    N7 79-
    N8 80-99
The prototype takes 60-80 seconds to complete the HEP mode lock.
/* 11/17/2012 fixed accelerate transition sound play */
/* removed interrupts to notching; fixes multiple accel and decel issues; */
Changes from original:
1) trim notch step sounds to make head-room, amplify Wav files
2) tweak F9 brake sounds (wav sounds and behavior), F15 coupling (F3 is un-coupling), F12 wheel squeal
3) removed selectors for horn and bell; removed extra horn sequences
4) fix overflow bug in generic notching project
5) fix secondary acceleration transition in T_SPD_ACCEL1

Problems and exceptions:
1) In this project is able to make brake sounds stop automatically when using loop_INVERT.
  Digitrax's default is CV132=127 but that bunches the notches at the lower portion
  of the throttle range.  127 or higher is OK when your motor takes very little current.
  A value of 64 will spread the notches across the whole range, but may leave your
  engine moving too fast. It should run at scale speeds and notch.
  Use F6 to notch up for RPMs you want. Note: F6 also turns off BEMF
  and effects sound probles (motor slow down).
3) Head-room is very limited. I tested up to 500,000 bytes. Anything greater than that may
    not load and run. Test this by un-assigning wheel squeal or another wav file, re-download
    and try. I have never been able to use the very last segment of memory in a SoundBug.
    If you have a 416 or the like there is plenty of memory available.
(A) Function Key Usage:
F0-     Lights           [disables startup sounds when on during initialization]
F1-     Bell
F2-     Horn    CV150 selects Horn type, at rest 2 or 3 toots depending on direction                
F3-        Auto Coupler    [Autocoupler/brake set by  CV151 max spd] F15 on for un-coupler
                        [Leave F3 on for auto coupler]    
F4-            Light functions here:    
F5-     Dynamic brakes            [Handbrake while stopped] [auto notch down with F7 on]                            :
F6-     Bell and  [This project changes F6 for switch speed.
        With F6 on the motor will be slowed by about half when CV54=1.    
            Bell is disabled by F18
F7-     Manual notch down        [If CV155 is not 00]
F8-     Mute control            [F8 to ON is muted]
F9-     Brake squeal            [Leave F9 off for auto brakes] [toggle F9 to off =auto notch up with F11 on,
                                    toggle to on will notch down with F7 on]
F10-     Grade crossing horn sequence    [Bell stays on until F10 off]
F11-     Manual notch up            [If CV155 is not 00]
F12-    Wheel Squeal    (continuous when moving) [Disables bell on F6]
F14-     Air features disable    [F14 off enables pop-off, drier and compressor]
F15-     UNCoupling                 [Leave on for auto toots]
F16-    Disable horn on distance event
F17-    BOX car Boom
F18-    Bell is disabled by F18
F19-    HEP mode         (plays HEP startup and continuous notch sounds)
F20-    Disable hard auto brake
F21- Notch 1
F22- Notch 2
F23- Notch 3
F24- Notch 4
F25- Notch 5
F26- Notch 6
F27- Notch 7
F28- Notch 8
(B)    Sound FX defined CVs:         [sound project download reset value in sq. brackets]

CV58    Master Volume, 0-15        [9]

CV122    Product type, 12 = Digitrax SFX sound decoder     (Read Only Value)
CV123    Hardware version                   (Read Only Value)

CV132    Notch rate (higher values = closer spacing)    [64 or 127 for wider]
CV135    Volume when muted                [33]

User configurable Sound CV's:

CV140    Prime mover volume        0-64    [60]
CV141    Bell volume                0-64    [25]
CV142    Horn volume                0-64    [60]
CV143    Air features volume        0-64    [40]
CV144    Dynamic brake volume        0-64    [50]
CV145    Misc volumes                 0-64    [40]        
CV146    Bell delay (1 = 24mS)          1-100    [7]
CV147    Drier rate (1 = about 2 secs)      1-64    [10]
CV148    Compressor start rate            1-100    [30]
CV149     Compressor run time                1-100    [20]
CV150    Horn select: 0 = default, 1 = playable, 2 = alt horn    [0]
CV151     Peak speed for auto coupler/brake with F3 on  0-60    [48]
CV152    Author ID    various        [0]
CV153    Project ID                [0]
CV154    Auto horn signals: 0 = Off, 1= On [1]
CV155    Notching mode: 0 = Auto, 1 = Semi auto, 2 = Manual [1]    

Notch test notes:
    1) hex 0x70 is the largest 3 bit value (1110000) so  test any 3bit value for <= 0x70 (1110000) hex 0x80 will overvlow mask (10000000)
    2) Auto notching will not exceed notch 5 UNLESS max speed curve value is >60 (60-254) due to the built-in algorithm inside the decoder.
    3) This means that a curve that limits to slow speed operation < 60SMPH will not get high revs.
    4) It uses the SVC132 notch rate to time the change in notch.
    5) It does not ever increment in amounts other than 16 (0x10).
    6) So slow speed operating AUTO-notch range is limited from 0-4 (0x40)
    7) HOWEVER: Operator selected notching will raise the notch value above this due to the  NOTCH_INC value.


(C) General Notes

This is a functional tested version of a project using individual sound recordings for each prime mover notch setting. These
prime mover sounds can be played in three modes determined by CV155: automatic, semi-automatic and manual notching. In auto
mode, the prime mover notch is determined by the current speed setting, and is adjustable using CV132. In semi-auto mode,
the same is true but it is possible to "throttle up" to higher notches using F11 and F7, if you want your engine to sound
like it is working harder. Manual mode offers full control of the notch setting using F11 and F7, so you can throttle down
to idle and turn on dynamic braking while coasting downgrade.

Other features available in this project include:
- Automatic grade crossing horn sequence with bell
- Optional highball and backup horn signals while stopped
- Dynamic brakes at speed, or handbrake while stopped
- Automatic coupler sounds when changing direction at low speeds
- Automatic brake squeal sounds when decelerating to a stop
- Manual brake squeal on F9 and moving

This sound project has been assembled from Digitrax-supplied sound clips as well as new sounds from custom recordings.

Thanks are due to Alex Stroshane, Fred Miller, Bob Grosh, Jim Walton and A.J. Ireland for their prior work in developing sound projects.

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