Description
Czechoslovak ECHRO Electrochemical Long-Delay Demolition Firing-Device Kit – Inspected January 18, 1962
Item Overview
This Czechoslovak ECHRO kit contains an electrochemical long-delay firing device used by military engineer troops with demolition charges and mines. ECHRO abbreviates elektrochemický rozněcovač, meaning “electrochemical firing device.” It is not a mine and was not made for one specific weapon system. The inspection slip accompanying this example is dated January 18, 1962.
Identification and Included Components
The set is identified by its brown Bakelite ECHRO body, removable cover, three covered battery compartments, circular fourteen-position delay selector, selector jumper, electrolyte fittings, and original Czechoslovak paperwork. Based on the visible contents, this should be described as a near-complete kit rather than a confirmed complete example.
- Bakelite ECHRO firing device and cover
- Fourteen-position delay selector and jumper
- Three covered battery compartments
- Electrolyte ampoule and small tools
- Sealing petroleum jelly with instruction sheet
- Original ECHRO operating instructions
- Triangular accessory container
- Original cardboard box and inspection slip
- Inspection date: January 18, 1962
- Published device diameter: approximately 132 mm
- Published device height: approximately 107 mm
- Published device weight: approximately 1.2 kg
Function and Construction
The ECHRO used batteries to power an electrochemical cell that gradually released a spring-loaded striker after an extended delay. Electrical resistances connected to numbered selector sockets controlled the delay period. When equipped with its original Žk combined detonator assembly, the device could initiate a demolition charge or mine. Substituting an electrical contact plug allowed it to serve as a long-duration timer or electrical switch. This set does not contain the original explosive Žk detonator.
Delay Selector on This 1962 Example
The selector ring photographed with this kit is marked for delays of 1, 2, 2.5, 5, 11, 14, 21, 37, 48, 60, 74, 96, 120, or 150 days. Later ECHRO references list a different fourteen-position table extending beyond 168 days. That difference may reflect changes in production, calibration, or documentation. The markings on this specific 1962 example are used for this listing.
Documented Application
The ECHRO was general-purpose Czechoslovak engineer equipment for delayed initiation of demolition charges and mines. It was intended for extended-delay tasks involving large structures and lines of communication. Its alternate contact plug allowed the same device to close an electrical circuit after the selected period. It was therefore a reusable equipment design with more than one engineer application, not a dedicated component of a single mine or demolition charge.
Product History
ECHRO equipment served during the Cold War period and remained documented in later Czechoslovak engineer manuals. Later references describe three Type 142 cells and a revised delay table, while the paperwork with this earlier set specifies three No. 140K 1.5-volt batteries and the photographed selector carries different delay values. These differences help document changes made during the ECHRO’s service life.
Czechoslovak Engineer-Equipment Background
Czechoslovak engineer troops maintained specialized equipment for constructing obstacles, preparing demolitions, handling mines, and denying important routes or structures. Long-delay devices allowed an engineer plan to continue after personnel had left the immediate area. Because the ECHRO could work with either a detonator assembly or an electrical contact plug, it belonged to the broader engineer-equipment inventory rather than one particular weapon family.
History of Use
Military references describe the ECHRO as suitable for delayed demolition work in varied weather conditions. Operators recorded the device number, selected delay, and time of connection because its delay could extend for weeks or months. The January 18, 1962 inspection slip with this set places it within the documented Cold War service period, although it does not establish that this particular device was used operationally.
Condition
This is an inert historical display set with its Bakelite firing device, cover, selector components, accessories, paperwork, cardboard box, and dated inspection slip. The three No. 140K 1.5-volt batteries are not visible and are not represented as included. The original explosive Žk detonator is not present. The remaining contents make this a near-complete ECHRO kit rather than a confirmed complete military issue set.
Ideal For
This Cold War Czechoslovak engineer-equipment set is suited to collections and displays focused on demolition equipment, military engineering, firing devices, EOD history, Warsaw Pact material, and Czechoslovak military technology.
- Cold War military-equipment collections
- Czechoslovak and Warsaw Pact displays
- Military engineering and demolition exhibits
- EOD and firing-device reference collections
- Museum and educational displays
Approx length 6.25", Approx width 6.25", Approx height 5", Approx weight 3.8lbs.
Pictures are stock images of our inventory. Unless otherwise noted, you will not be receiving the exact item shown in the pictures. The pictures are representative of the item’s general condition. The item you receive might be slightly better, or worse, condition than was shown in the pictures.
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