Tam Valley Depot

NEW - Add on for DCC systems that puts the DCC signal in the air and powers your locomotive from an on-board battery.  Track cleaning not required.

Here are pictures of the unit installed in a Bachmann On30 Davenport (gas-mechanical). The DRS1 receiver is taped to the roof of the cab (you can see the green power LED). The battery (lower right) is three 110 mAh Lithium polymer cells to make 11.1 volts.  It is connected to the receiver with a plug so it can be turned off between uses and recharged when needed. It will run the locomotive for an hour or more of light use switching.  First I programmed the address of the locomotive on the programming track and then the receiver was connected to the Bachmann decoder by clipping the wires to the wheels (red and black) and splicing in the DCC wires from the DRS1 (green).

619-992-2234 

128 S. Line St., Linsdale, PA 19446

215-412-7715

DRS1 Receiver, 916 Mhz
Receives the wireless DCC signal and creates DCC on-board from the battery to replicate the DCC signal to an existing DCC locomotive decoder. Works with all DCC decoders including sound decoders that need 1.5 Amps or less. Replaces the wires from the wheels. Battery not included (11.1V Lithium ion batteries reccomended - do not exceed 15V). Installation required. Transmitter (see below) required. Comes with wiring harness of 30 ga. flexible stranded wire. Receiver is 34mm x 18mm (1 5/16" x 3/4") with the blue antenna adding about 3mm (1/8").  The antenna can be repositioned by desoldering. The unit is 4mm (5/16") thick. Maximum continuous current is 1.5 A.

DRX001  $59.95 USD

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Note: when removing the wiring harness be sure to pull gently on the green plastic connector case with a pair of nippers or sharp tweezers - do not pull the wires or they will come off! Maximum voltage for the battery input is 15V DC - do not exceed! Connecting the battery backward will cause the board to start heating up quickly. It will not cause damage if remedied within a few minutes but do not leave this way!

Wiring diagram for the DRS1 receiver.  Wire colors correspond to wires on the harness.

The recommended battery is an 11.1V lithium polymer (lithium ion) 3-cell battery of 100 mAh or higher. In a test I found that a 120 mAh battery will run my sound-equipped Forney for 40 minutes with the wheels slipping. Obviously, the larger the battery the longer the time between charges. 7.2V, 2-cell batteries will work with most locomotives with some loss of pulling power.

An on-off circuit to disconnect the battery is needed. This can be a plug you pull apart or it can be switch.

If a lithium battery ledt connected after discharging it will be damaged. (Some batteries, like the SparkFun batteries reccomended below, come with a small circuit board to prevent this and to prevent over-charging.)

Be sure to read the instructions that come with lithium batteries - they are not as tolerant as other types of battery.

We recommend removing your battery and charging it in a coffee cup as they have been known to explode. If you cannot remove it, then charge it at the slowest rate possible on your charger.

DRS1 Transmitter, 916 MHz

Takes the DCC signal from your existing command station and puts it in to the air to be picked up the receiver(s) in your locomotive(s) (see above). Simply connect to the back of your command station to the rail outputs and place in the center of the room near the ceiling.  Use twisted pair or speaker cable for long runs (> 10 ft) back to the command station. Since the transmitter only draw 21 mA, the wire can be as small as 28 ga. Only one transmitter is needed for the entire layout. This device transmits low power radio frequencies on the Instrument-Scientific-Medical (ISM) band (also used by 900 MHz cordless phones) with a range of about 50 feet. Please see disclaimers below before ordering this product.

An antenna is required.  You can use the antenna below or connect a 155mm (6-1/8")" length of wire to the center post of the gold RPSMA connector. Generates 1 mWatt of power into a 50 Ohm antenna.

TRX001  $59.95 USD

916 MHz Antenna 1/4 Wave Whip w/ RP-SMA Connector

Screws on to the gold connector on the transmitter (Linx ANT-916-CW-QW).

ANT001  $9.00 USD

Exactly as above except it is for 868 MHz.

ANT002  $9.00 USD

Gold-plated Breakaway Connectors - I use these to make connections between the battery and the receiver.  They are small, easy to plug and unplug and electrically reliable. Receptacle - Digi-Key SAM1115-32-ND. Header - Digi-Key SAM1111-32-ND.

Litium Polymer batteries - All RC stores that carry small electric airplanes and helicopters will have small 3-cell batteries. They can usually be made smaller by cutting off the heavy casing and adding a smaller connector made from breakaway headers (above).  these batteries usually do not have circuit boards built in to them to protect them from over-charging and over-discharging. You can make your own 3-cell packs from these excellent batteries from SparkFun Electronics that do have the protective boards built-in: 400mAh LiPo.  110 mAh LiPo. Another source is All-battery.com - we like the 240 mAh Tenergy w/PCB.

Battery Charger. I like the HiTec X1. It can charge just about anything. It is not easy to use but then none of the better battery chargers are - they are just too complicated. I got mine by searching amazon but most RC stores have them and the helpful person behind the counter may be able to show you how to set it up to charge the battery you just bought.

Electronic Switch - You need a switch rated at least 1.5 Amps to turn the battery on and off. These can be quite big and bulky. An alternative is to use an electronic switch.  This has a small momentary tactile switch that is used to toggle the power - Pololu Pushbutton Power Switch. I have mounted the pushbutton so that it can be toggled by a bamboo skewer through a small hole or window. The board has a green LED so you can tell when the power is on for locomotives without sound.

Reed Switch - An even better power switch can be made by replacing the pushbutton on the Pololu Power Switch with a small reed switch.  You can then turn the power on and off with a small magnet. The reed switch can be hidden inside the shell.  A small reed switch is available from Digi-Key 374-1083-ND. Small super magnets are available at hardware stores. I taped one to a small screwdriver to make my "magic wand" for turning my locomotives on and off.

Flexible Wire - TCS sells small very flexible 30 ga. wire in multiple colors. Also useful is solderable magnet wire from All Spectrum Electronics.

Frequently asked DRS1 questions:
Q: Can I consist DRS1 equipped units with my conventional DCC locomotives?
A: Absolutely. The DRS1 locomotive receives and obeys DCC commands as if it wre still connected to the track

Q: Can I program decoders in DRS1 equipped locomotives through the transmitter / receiver connection?
A: Yes, with Programming on the Main (Ops mode) you can program your locomotive. However, some decoders (e.g.Tsunami) will not allow changing the loco address in Ops mode. In this case you can attach the the decoder directly to  the pragramming track. The DRS1 has a plug that can be removed and connected to an adapter to make this easier.

Q: Can the receiver send commands and power to more than one decoder? I have several locomotives with separate sound and motor decoders
A: Yes. You can attach as many decoders as the current limit will allow.

Q: What about automated control from cab bus equipped modules like NCE mini-panels, loconet, xpress-net, NMRANet etc.
A: These are all cab-bus or accessory bus devices. The DRS1 does not change the way the cab-bus behaves in any way - it is connected on the track side of the command station.

Q: Can I still run these equipped locomotives at my club or friends layout?
A: No problem. Simply bring along your DRS1 transmitter and attach it to the track with some alligator clips in an out of the way location. You can now use your freinds throttles to run your wireless DCC locomotive (be sure to run it on the floor just to show off!).

Q: How many receivers will one transmitter accommodate reliably.
A: There is no limit. The receivers do not draw any power from the transmitter.

Q: Is there a way to prevent locomotives from continuing to run all the way to the floor if they do leave the track,
A: Yes, grab them. This is a portential new danger for on-board battery power (and keep-alive circuits).