I did not follow every single one of these good tips, but I sure did appreciate the diagrams with the colored lines and power blocks. It's like he knows what's it like to be me, to have some fear of misinterpreting schematic diagrams, and even basic electrical words like "ground". But I do my best. This text below by Gregory Braun, RIP Track Power Modern AFX and Tyco slot car motors require a power supply producing 18 to 20 volts of direct current (VDC), while older Model Motoring cars require 20 to 24 VDC. The wall-outlet power pack supplied with most boxed racing sets is not sufficient for use on large table-mounted racing layouts. DC power supplies normally have two specifications, the output voltage and the output current. Modern HO slot car motors require at least 18 VDC, and 1 ampere or more of current for proper operation. Most of the DC power supplies currently being manufactured provide only 12 to 13.8 VDC. These WILL NOT work for HO slot car tracks. They will however work properly for larger 1:32 and 1:24 scale slot car tracks. A good quality DC power supply is essential to safe, trouble-free racing and prolonged motor life. Investing in a good power supply will quickly pay for itself in motor savings alone. A good rule of thumb to use when determining the size of the power supply required is to multiply the number of lanes by 1 ampere. Especially long layouts or very hot motor armatures may require more power, but 1 ampere per lane should be sufficient for all but the most demanding racing situations. A 5 ampere DC power supply would be a good choice for a long 4-lane racing layout. This should provide sufficient power with an adequate reserve. Power needs to be applied evenly around the entire race track. Slot car tracks with lane lengths greater than about 20-25 feet will need to have power applied at several locations. The rail connections at the joints in plastic sectional track are the single largest factor contributing to voltage drops as the cars move farther and farther away from the power terminal track. It is often said that power should be applied every 15 or 20 feet for an even power distribution. This is true, but an even better way of determining power terminal track spacing is to count track joints. It is the joints that rob your track of power not just the length. Applying power every 12 to 15 track joints will assure that your track is properly powered. It is important to determine where power will be applied before you build your track and mount it permanently to a table. Racers who skimp on adequate track power distribution will be disappointed when they have completed their track and find that cars slow dramatically on those sections of the race track farthest from the power taps. Replacing the power supply with a unit producing higher amperage has very little effect on power distribution. Inadequate power distribution produces voltage drops around the circuit. All of the amps in the world can't overcome this drop in voltage though. Powering each lane with 1 or 2 amperes is sufficient if power is distributed evenly. It's far more important to apply track power evenly around the racing circuit than it is to have a high-output power supply feeding a single set of power terminal tracks. Regardless of the power supply output, cars will slow down dramatically as they travel farther away from the power source. Generally speaking, a 4-lane race track mounted on a 4x8 foot table would require 2 or 3 power taps, while a 4x12 foot table would probably require at least 4 or 5 taps. Even larger and longer race tracks may need as many as 10 power taps. Count the joints for a single lane and then divide by 12 or 15 to get a better idea as to how many power taps your particular track design requires. Commercial Power Supplies Astron is a good source of high quality DC power supplies for HO slot car racing layouts. The Astron catalog lists a nice 0-30 Volt Variable DC Power Supply producing 10 amperes of power. Astron power supplies are fully regulated. A regulated power supply eliminates power surges associated with other multi-lane power supplies. Three different power supplies are available: - Astron - 8 Amp / 10 Amp ICS - $195.00 - Astron - 18 Amp / 25 Amp ICS - $355.00 - Astron - 27 Amp / 35 Amp ICS - $395.00 The Astron Series of DC power supplies have 0-30 VDC variable voltage outputs as well as adjustable current output ranging from 1.5 amperes to the full load rating. I'm selling the Astron Series of DC power supplies for both HO and 1:32 scale slot car racing on my Order Form page. A variable voltage DC power supply will also allow you to reduce the voltage when young or inexperienced racers drive your cars. Reducing the voltage to 9-12 VDC will make it much easier for very young children to race without having the cars constantly flying off the track. As their car handling skills improve you can increase the voltage gradually until they are using the full 18-20 VDC that modern HO tracks normally use. Power Requirements The table below shows the maximum peak current (amps) drawn by various types of HO slot car motors. HO-Slot-Car-Current-Requirements.gif Track Wiring Neat track wiring is important. Spend the extra time to properly wire your slot car racing layout. Solder all connections whenever possible, or use crimp-on connectors if you do not want to solder. Use 14 of 16 gauge stranded wire for all power, controller and track connections. The increased wire gauge will guarantee safe racing. The diagram below illustrates the track wiring required for a single lane. Expand this for the number of lanes your racing layout has. slot-car-wiring.gif A 2 ampere fuse should be sufficient to protect your car and controller. If you run hotter motor armatures you may need to increase the fuse rating to 3-5 amperes. Each lane should be individually fused. Do not use a single fuse for all lanes. If your controllers do not include a brake circuit eliminate the red wire running from the controller connection to the track power grid in the diagram above. If you have both types of controllers you can retain the brake wiring circuit and only use it for those controllers that have braking built in. See the Construction section of this web site for step-by-step pictures of a 4-lane raceway being built and wired using the wiring schematics below. The diagram below illustrates typical 4-lane wiring using standard dual-row barrier terminal blocks for all power, controller and track connections. This wiring method uses solderless crimp-on spade lugs for all barrier terminal connections. Longer race tracks will require power to be applied at several locations around the racing circuit. The barrier terminal blocks on the right side of the diagram below illustrate a wiring scheme for a track with power applied at two individual points on the race track. You can add extra terminal blocks if you plan to apply power in more than two locations. The actual length of the wires between the track terminal blocks will be longer than those illustrated below. slot-car-4-lane-wiring.gif The 4-lane track wiring diagram shown above can be used with a single power supply or individual power supplies connected to each lane. If a single power supply is to be used bridge the four positive power lines (white wires) together with a four position barrier terminal jumper. Use a second four position barrier terminal jumper to bridge the four negative power lines (red wires) together as well. Parts Required 3 - 8 Position Barrier Terminals - RS 274-670 4 - 3 Position Barrier Terminals - RSU 11673209 4 - #8 Spade Terminal Packs - RS 64-3128 1 - 18-14 Gauge Tap-In Pack - RS 64-3052 1 - 8 Position Jumper (Optional) - RS 274-650 The 18-14 Gauge wire tap-ins specified above are used to connect controller brake circuits to the negative power lines. The 4-lane track wiring diagram shown below is a simple variation on the previous diagram. It employs a 4 position barrier terminal at each driver station to tie the brake circuits together instead of wire tap-ins as used above. The 3 Position Barrier Terminal - RSU 11673209 used in the diagram above is a special order item, whereas the 4 Position Barrier Terminal - RS 274-658 used in the diagram below is available at all Radio Shack retail outlets. slot-car-4-lane-wiring-2.gif The 4-lane track wiring diagram shown above can also be used with a single power supply or individual power supplies connected to each lane. If a single power supply is to be used bridge the four positive power lines (white wires) together with a four position barrier terminal jumper. Use a second four position barrier terminal jumper to bridge the four negative power lines (red wires) together as well. Parts Required 3 - 8 Position Barrier Terminals - RS 274-670 4 - 4 Position Barrier Terminals - RS 274-658 4 - #8 Spade Terminal Packs - RS 64-3128 1 - 8 Position Jumper - RS 274-650 1 - 8 Position Jumper (Optional) - RS 274-650 The 8-position jumper specified above can easily be cut into the two 4-position sections required for race tracks using a single power supply. Simply remove the two jumper strips if you change to individual power supplies for each lane at a later date. The wiring diagrams illustrated above assumes that power fuses are installed at each of the four driver's stations. Driver's Stations Simple and very attractive driver's stations can easily be made to allow racers to connect their hand controls. Purchase a 2x4 inch plastic project box from Radio Shack (Part No. 270-1802) for each lane. These boxes come with both a plastic and aluminum cover. Use the plastic cover and paint it to match the color of the lane it will control. Only the plastic cover is required, so save the aluminum cover and the lower section of the box itself for other projects. Hand controls normally have black and white power wires and a red brake connection. You can purchase corresponding black, white and red banana jacks and plugs from Mouser Electronics. Do not use the banana jacks and plugs sold at Radio Shack though as these are very poorly made and will not maintain a good electrical connection. Radio Shack does not offer a white banana plug or jack. It is very important that you maintain the red, white and black color scheme so as not to confuse racers. The diagram below illustrates a single lane's driver station. The banana jacks are mounted in 5/16 inch holes drilled on 1 inch centers. slot-car-drivers-station.gif If you have hand controls that will always be used with your race track install banana plugs on each of the three controller leads, maintaining the proper color coding. If you would like to use alligator clips to connect your hand controls then remove the hoods from the banana plugs and just insert them in the jacks. These bare plugs will form posts that can be used to attach the alligator clips to. If you mount banana plugs on some controllers and leave the alligator clips on other hand controls then purchase some extra banana plugs to use as posts when you want to use your hand controls with alligator clips. slot-car-drivers-station-fused.gif If you want to add a power fuse at each driver's station purchase a 2x6 inch project case instead (Cat No. 270-1804). The additional length will allow enough room for its mounting. The list below contains the Mouser Electronics part numbers for the plugs and jacks you'll need to purchase: White Banana Plug Red Banana Plug Black Banana Plug 530-108-0901 White Banana Jack 530-108-0902 Red Banana Jack 530-108-0903 Black Banana Jack 530-108-0301 White Banana Jack 530-108-0302 Red Banana Jack 530-108-0303 Black Banana Jack For a typical 4-lane layout you will need to purchase four (4) of each of the items listed above. The Mouser Electronics web site has all of these items available on-line. You can also place an order by calling their toll-free number at 1.800.346.6873 See the Construction section of this web site for pictures of fused 3-wire driver's stations being installed in a 4-lane raceway. If you would prefer to purchase ready-made driver's stations as described above see the For Sale section of this web site. Custom Power Supply If you feel comfortable building your own electronics projects you can easily make the DC power supply illustrated below for under $15 dollars per lane. slot-car-1-lane-schematic.gif If you would like to provide individual power supplies for each lane of your race track this simple design will produce 3.5 amperes per lane. This power supply would be ideal for large layouts or HO Slot Cars using hot armatures. This power supply design uses only three (3) components available from Radio Shack's web site or your local Electronics Parts Store. Parts Required - T1 - 16 Volt - 3.5A CT Transformer - RS 900-2707 - D1 - 50 Volt - 10A Full Wave Rectifier - RS 900-4788 - C1 - 2200 uF - 35V Electrolytic Capacitor - RS 900-1973 A 4-lane power supply using four (4) of each of the components listed above will cost you less than $60.00, yet will provide 3.5 amperes per lane, for a total power output of nearly 15 amperes. This power supply design uses a classic full wave diode bridge circuit (D1) to rectify the transformer's secondary AC output (T1). The capacitor (C1) smoothes DC ripple. The instructions and schematic for building your own custom power supply have intentionally been left rather vague. If you're comfortable working with the 120 VAC primary side of the transformer, or know someone who is, perhaps a HAM radio operator, then this would be a simple one-evening project. Due to the high voltage primary wiring on the transformer this project should only be undertaken by someone who understands what they're doing. This is NOT a good first project for the electronics novice! Power Terminal Tracks Power terminal tracks from Tyco and Tomy are expensive and will not allow you to use individual power supplies for each lane. Longer layouts need to have power applied at several locations on the layout. Using manufactured power terminal tracks can become quite costly. This section describes a method of making your own power terminal tracks from standard straight track sections. Making your own power terminal tracks is quite easy. All you will need is a soldering iron, soldering flux for electronics, and some rosin-core electrical solder. You will also need some short lengths of 16-18 gauge connection wire. Note: The information provided here can also be used to attach wires to dead track sections used for electronic lap counters. Start by placing a straight section of slot car track upside down on a towel dampened with cold tap water. The damp towel will prevent heat from the soldering iron being transferred to the plastic track. The metal power rails running along each side of the guide pin slot are secured to the plastic track itself at 3 inch intervals. Locate a pair of these mounting points midway down the length of the straight track section and place a small dab of soldering flux on the exposed metal rail mounting points. Cut two 12 inch lengths of hook-up wire and strip away 1/4" of the insulation from one end of each wire. With a hot soldering iron heat the exposed wire and apply a small amount of solder to the heated wire. This tinning process will make later attachment to the metal power rails much easier. Place one of the tinned hook-up wires at the point on the metal power rail where you had previously applied soldering flux and hold your soldering iron on the joint. Apply a small amount of additional solder once the flux begins to boil, and then carefully removed the soldering iron. Let the solder cool naturally, do not blow on the heated solder though, as this may fracture the soldered joint you just made. Repeat the process described above for the remaining three metal power rails on a two-lane section of plastic slot car track. Longer slot car tracks will require power terminal tracks placed at intervals around the circuit. The running length of track between power terminals is not nearly as important as the number of track joints separating the power terminals. The track joints themselves are the largest source of electrical resistance. A good rule of thumb is to use a power terminal track for every 12-15 track sections. See the Construction section of this web site for pictures of power terminal tracks being installed in a 4-lane raceway. If your slot car track employs a dead track section for an electronic lap counter use two power terminal track sections, one before and one after the dead section. If you would prefer to purchase power terminal tracks made using the process described above see the Order Form section of this web site. Tomy AFX 2-Lane Dual Power 2-Lane Tomy AFX track owners can easily configure their tracks to use individually powered lanes by simply adding a second Tomy AFX power terminal track and power pack. The diagram below illustrates how to wire any Tomy AFX 2-lane race track to use individually powered lanes. This method will double the power available to each car, and eliminate the power surge problems associated with a single power supply. slot-car-2-lane-afx-wiring.gif Simply insert a second Tomy AFX power terminal track into the layout with the connection block exiting from the same side of the track as the first one. Then connect one power pack and one hand control to each power terminal track. Each hand control needs to be connected to the corresponding lane it will regulate. The diagram above shows two power terminal tracks placed next to one another for simplicity, but they can actually be placed anywhere around the raceway to allow the two drivers stations to be located at different points around a larger table. Tomy AFX 4-Lane Quad Power 4-Lane Tomy AFX track owners can easily configure their tracks to use individually powered lanes by simply adding two additional Tomy AFX power terminal tracks and power packs as illustrated below. 4-lane-afx-wiring.gif Track Power Testing Nothing is more frustrating than racing on a slot car track with corroded or loose power rail connections. Here is a simple and fool-proof method of locating bad track joints. Start by first removing the last track section before the power terminal track and then slowly drive a car around the track until it stops. Whenever the car stops inspect and clean the power rail joints at the track section just before the loss of power occurred. Repeat this process for all lanes until the car travels around the entire circuit without slowing or stopping. slot-car-power-test.gif Finish up by replacing the last section of track and now you'll have a race track without any power losses.