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Vietnam War USGI Detector Set TRC-3A
Dorsett Electronics 127.400 MHz Seismic Intrusion Transmitter & Geophone Probe
Visual Reference: Clean, legible data plate of the US Military TRC-3A detector set, showing contract DAAK02-72-C-0321 and FSN 6350-179-1593.
Detector Set, Model TRC-3A
Up for sale is a highly collectible, original Vietnam Era USGI Detector Set Model TRC-3A. Manufactured by the Dorsett Electronics Division of LaBarge Inc. under military contract DAAK02-72-C-0321, this specific unit is stamped for the 127.400 MHz frequency. These devices served as covert tactical surveillance sensors deployed along defensive perimeters, trail networks, and borders to monitor troop and vehicular movements.
- Historic Battlefield Intelligence: These devices served as covert seismic sensors deployed along defensive perimeters, trail networks, and borders to monitor troop and vehicular movements during the Vietnam conflict.
- Proven 1/4-Mile Transmission & Sensitivity Range: Real-world tested in a rural environment in the early 1990s! The transmitter successfully and clearly broadcast telemetry from a distance of 1/4 mile away.
- Adjustable Geophone Probe: Features 5 selectable sensitivity levels. Testing confirms the upper settings are incredibly sharp—capable of triggering from passing deer, wildlife, or vehicular traffic 1/4 mile from the probe—while the lowest setting provides a perfect baseline for localized target monitoring.
- Fully Functional Gear: Unlike most surplus electronics offered strictly \"as-is\", this unit has been completely bench-tested and field-verified to operate exactly as intended as of 06/27/2026.
- Modern Battery Upgrade Included: To save you from sourcing expensive, obsolete military cells, this set includes a brand-new pair of rechargeable 9V batteries that easily juice up using a standard USB-C cable.
Item Specifics BRAND: Dorsett Electronics / LaBarge Inc. ITEM TYPE: Seismic Intrusion Detector FREQUENCY: 127.400 MHz FED STOCK NO: 6350-179-1593 (FSN) CONTRACT NO: DAAK02-72-C-0321 UNIT IDENTIFIER: 04 0532 ERA: Vietnam War Era (Contract 1972) ORIGIN: Tulsa, Oklahoma, USA CONTENTS: 1x TRC-3A Unit, 1x Teledyne Geophone Sensor, 2x USB-C 9V Batteries CONDITION: Tested / Working Condition Report
Cosmetic & Structural Condition: This tactical detection unit is in very good, authentic military surplus condition with honest cosmetic wear consistent with age and field storage. The metal data plate text markings are remarkably clean and perfectly legible.
Notable Flaw (Please Read): The rubber strain-relief casing where the sensor wire enters the top of the geophone probe has a visible age-related crack. Because of this, the cable lacks its original stabilizing support and could weaken if bent back and forth repeatedly at that junction. Additionally, if left unsealed, moisture could enter this crack and make its way toward the internal electronics during outdoor deployment in wet weather.
Functionality & Fix: Crucially, this set has been tested today and works exactly as intended despite the cracked rubber boot. The internal wiring is intact. This is a simple fix for the next owner using heat-shrink tubing, liquid electrical tape, or silicone wrap to reinforce and weatherproof the joint. Includes a brand-new pair of USB-C rechargeable 9-volt batteries!
Shipping & Guarantee:
- I will use the most economical and secure USPS method available at my online postage rate.
- Premium Packaging: The detector set will be packed carefully with protective padding to prevent loss or damage in transit, ensuring it arrives safely.
- Satisfaction: 30 day, 100% money-back guarantee (Buyer pays return postage if unsatisfied).
Add this rare, working TRC-3A Intrusion Detector to your Vietnam War militaria collection today.
