{"title":"In Stock Detectors\/Railroad","description":"\u003cp\u003eProfessional model railroad \u003cstrong\u003e\u003cu\u003e\u003ca href=\"\/collections\/detectors\" target=\"_self\"\u003edetectors and occupancy sensors\u003c\/a\u003e\u003c\/u\u003e\u003c\/strong\u003e from \u003cstrong\u003e\u003cu\u003e\u003ca href=\"http:\/\/www.circuitron.com\/\" target=\"_self\"\u003eCircuitron\u003c\/a\u003e\u003c\/u\u003e\u003c\/strong\u003e, \u003cstrong\u003e\u003cu\u003e\u003ca href=\"https:\/\/www.digitrax.com\/\" target=\"_self\"\u003eDigitrax\u003c\/a\u003e\u003c\/u\u003e\u003c\/strong\u003e, and \u003cstrong\u003e\u003cu\u003e\u003ca href=\"https:\/\/www.ncedcc.com\/\" target=\"_self\"\u003eNCE\u003c\/a\u003e\u003c\/u\u003e\u003c\/strong\u003e. Block occupancy detectors, grade crossing sensors, transponding receivers, and rolling stock detection for automated signaling and layout control. Essential for DCC operations, computer control, and realistic railroad automation. Complement with \u003cstrong\u003e\u003cu\u003e\u003ca href=\"\/collections\/controllers-railroad\" target=\"_self\"\u003eDCC controllers\u003c\/a\u003e\u003c\/u\u003e\u003c\/strong\u003e and \u003cstrong\u003e\u003cu\u003e\u003ca href=\"\/collections\/connectors-blocks\" target=\"_self\"\u003ewiring components\u003c\/a\u003e\u003c\/u\u003e\u003c\/strong\u003e for complete layout infrastructure.\u003c\/p\u003e","products":[{"product_id":"800-5202-dt-2-grade-crossing-detector","title":"800-5202 DT-2 Grade Crossing Detector","description":"\u003cp\u003eCIRCUITRON designed the DT-2 to be the most advanced DC track power grade crossing detection circuit available at any cost. It is completely independent of train length, and it will duplicate prototype grade crossing action for a single locomotive or a 100-car train. The DT-2 is completely bidirectional and includes the 4 Opto-Sensors required for a normal installation. The integrated circuit memory on the DT-2 does not require that a sensor remain covered in order to provide an output; the sophisticated circuitry will always maintain the output ‘ON’ for any length approaching train just until the last car clears the crossing. If a train should stop short of a crossing and then back away, the DT-2 will detect that, also, and turn the output ‘OFF’. The DT-2 is fully assembled on a 3” x 3” printed circuit board and will operate equally well from any 10-18 volt AC or DC power source. The output of the DT-2 provides a connection to the common or ground (-) side of the circuit and is capable of controlling DC powered loads up to 250 ma.  Although the DT-2 is one of our more costly circuits, it is still an outstanding value for serious model railroaders who demand nothing less than the ultimate in realism for their layouts. Please see note regarding flashers above.\u003c\/p\u003e\n\u003cp\u003eNOTE: If the DT-1 or DT-2 are installed on layouts using Command Control, the train direction sensing feature is defeated, and a manual panel switch must be used to establish the direction of travel prior to a train arriving at the crossing. Although this is somewhat clumsy, it is not much different from the prototype where a dispatcher must set the travel direction of signals on bi-directional trackage.\u003c\/p\u003e","brand":"Circuitron Electronics","offers":[{"title":"Default Title","offer_id":46404119298279,"sku":"TOR5202IH","price":44.21,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0636\/7798\/9095\/products\/800-5202-dt-2-grade-crossing-detector-mpm-hobbies.jpg?v=1750785616"},{"product_id":"800-5521-bd-1hd-block-occupancy-detector-opto-electronic","title":"800-5521 BD-1HD Block Occupancy Detector- Opto-Electronic","description":"\u003cp\u003eProvides operating 2 color Block Signals for bi-directional train traffic. The system will provide positive “Occupied” indications whenever any piece of rolling stock is within the block and a “Clear” indication when no train is detected. The system will be able to power 2 color signals at each end of the block without additional drivers.\u003c\/p\u003e\n\u003cp\u003eThe BD-1HD is identical to the BD-1 but includes heavy duty output transistors to power lamps in large scale signals. Each output on the BD-1HD can control 500 ma.\u003c\/p\u003e","brand":"Circuitron Electronics","offers":[{"title":"Default Title","offer_id":46688016728295,"sku":"TOR5521IH","price":29.96,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0636\/7798\/9095\/products\/800-5521-bd-1hd-block-occupancy-detector-opto-electronic-mpm-hobbies.jpg?v=1750785831"},{"product_id":"800-5250-df-1-grade-crossing-detector-with-flasher","title":"800-5250 DF-1 Grade Crossing Detector with Flasher","description":"The CIRCUITRON DF-1 is a full performance, single direction grade crossing detection circuit and alternating flasher on one circuit board. The DF-1 is remarkably low cost considering the outstanding performance it delivers and is the ideal setup for the modeler who does not require the bidirectional capabilities of the DT-1 or DT-2. The DF-1 utilizes our proven Opto-Electronic Detection and will provide accurate grade crossing.\u003cbr\u003eaction for a single locomotive or a 100-car train.  There are absolutely no modifications to rolling stock necessary. The DF-1 is completely independent of the track power and is compatible with AC or DC track power as well as command control systems (DCC). It may be used with any scale and requires a 10 - 18-volt AC or DC power source. The flasher section of the DF-1 has the same specifications as our FL-2 and can power two 250 milliamp loads (approximately 4 grain of wheat lamps or 10 LEDs per side). Other CIRCUITRON Detection circuits such as the DT-1, DT-2 or DT-3 below can be easily connected to provide control of the flasher section when detection on parallel tracks is desired. An Accessory OUT terminal is provided which will provide a GROUND [-] output whenever a train is detected. This terminal may be used to control Bells, Gates, etc. through the use of other circuitry such as the BR-1, BR-2, BR-3, GD-1 and ER-1\/ER-2 boards. The DF-1 printed circuit board measures 3” x 3”.","brand":"Circuitron Electronics","offers":[{"title":"Default Title","offer_id":46688112935143,"sku":"TOR5250IH","price":41.21,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0636\/7798\/9095\/products\/800-5250-df-1-grade-crossing-detector-with-flasher-mpm-hobbies.jpg?v=1750785833"},{"product_id":"800-5203-dt-3-grade-crossing-detection-circuit-single-direction","title":"800-5203 DT-3 Grade Crossing Detection Circuit- Single Direction","description":"The CIRCUITRON DT-3 Single Direction Grade Crossing Detection Circuit utilizes our proven Opto- Electronic Detection and will provide accurate grade crossing action for a single locomotive or a 100-car train. There are absolutely no modifications to rolling stock necessary. The DT-3 is completely independent of the track power and is compatible with AC or DC track power as well as command control systems (DCC). It may be used for any scale. The DT-3 may be powered from any 10 - 18-volt AC or DC supply and will control any CIRCUITRON Alternating Flasher, Bell Ringer Circuit, External Relay, etc. The DT-3 is constructed on a 2”x 3” printed circuit board.","brand":"Circuitron Electronics","offers":[{"title":"Default Title","offer_id":46688915587303,"sku":"TOR5203IH","price":26.23,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0636\/7798\/9095\/files\/800-5203-dt-3-grade-crossing-detection-circuit-single-direction-mpm-hobbies.jpg?v=1750785835"},{"product_id":"800-5201-dt-1-grade-crossing-detector","title":"800-5201 DT-1 Grade Crossing Detector","description":"The CIRCUITRON DT-1 is a bi-directional detection circuit designed for DC track power that provides an output whenever one of its Opto-Sensors is covered by a piece of rolling stock. Absolutely no modifications to the rolling stock are necessary.","brand":"Circuitron Electronics","offers":[{"title":"Default Title","offer_id":46688947634407,"sku":"TOR5201IH","price":30.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0636\/7798\/9095\/files\/800-5201-dt-1-grade-crossing-detector-mpm-hobbies.png?v=1750785836"},{"product_id":"800-5501-bd-1-block-occupancy-detector-opto-electronic","title":"800-5501 BD-1 Block Occupancy Detector- Opto-Electronic","description":"The CIRCUITRON BD-1 is an advanced, integrated circuit design Block Occupancy Detector utilizing our proven Opto-Electronic design which provides positive indication whenever a block-section of a layout is occupied by any piece of rolling stock. Two pair of CIRCUITRON Opto-Sensors (included) are mounted between the ties at the end points of the block that is to be protected. Any piece of rolling stock entering the block shades the Opto-Sensors from ambient room light which activates the logic circuitry on the BD-1 circuit board. No modifications to rolling stock are necessary. The BD-1 is bidirectional and will give proper indications even if a train leaves a block by reversing direction and backing out. The CIRCUITRON BD-1 also contains driver circuitry sufficient to power a pair of two-color LED (including 2 lead Bi-Color LEDs) or incandescent lamp block signals at each end of the protected block (LED-type signals must be wired with a common anode [+] configuration). The outputs on the BD-1 can control a maximum of 250 ma. For 3- color signaling, additional signal drivers will be necessary (see our SD-x series of drivers later in this section). The BD-1 requires a 10–18-volt DC input for proper operation. The power supply should be filtered for proper operation.  If you do not have a filtered power supply, the CIRCUITRON PS-1 filtered AC to DC Converter or PS-2 Regulated AC to DC Converter are ideal for this application. The BD-1 is constructed on a 2” x 3” printed circuit board.","brand":"Circuitron Electronics","offers":[{"title":"Default Title","offer_id":46689249788135,"sku":"TOR5501IH","price":29.96,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0636\/7798\/9095\/files\/800-5501-bd-1-block-occupancy-detector-opto-electronic-mpm-hobbies.gif?v=1705821415"},{"product_id":"800-5522-bd-2hd-block-occupancy-detector-current-sensing","title":"800-5522 BD-2HD Block Occupancy Detector- Current Sensing","description":"The BD-2HD incorporates a turn-off delay of approximately ½ second to prevent loss of detection due to dirty wheels, etc. The BD-2HD will directly drive either LED-type or incandescent lamp, 2-color block signals and the outputs have a maximum current capacity of 250 ma. The circuit boards are designed for easy daisy-chain wiring of multiple blocks and will snap into a section of our PCMT (Printed Circuit Mounting Track) for simple installation. The BD-2HD is constructed on a 2” x 3” printed circuit board and is available in standard 6-amp track power capacity.  The signal driving capacity of the BD-2HD is increased to 500ma. per output and will work well with large scale equipment.","brand":"Circuitron Electronics","offers":[{"title":"Default Title","offer_id":46693033017575,"sku":"TOR5522IH","price":29.21,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0636\/7798\/9095\/files\/800-5522-bd-2hd-block-occupancy-detector-current-sensing-mpm-hobbies.jpg?v=1750785851"}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0636\/7798\/9095\/collections\/image_5acfe4db-1207-434e-9870-2a14d58fc068.png?v=1774610430","url":"https:\/\/mpmhobbies.com\/collections\/in-stock-detectors-railroad.oembed","provider":"MPM Hobbies","version":"1.0","type":"link"}