Vietnam War TRC-3 Seismic Intrusion Detector Set 129.000MHZ Tested and Working

Description

I have done my best to test these individually but I'm not an expert on these units.  Vietnam War TRC-3 Seismic Intrusion Detector Set - Tested and all four units generate a tone Received on a Radio Shack scanner.  Frequency is 129.000MHZ and all four units are sequential 1-4.  Each unit uses two standard 9v batteries, not included (lithium recommended).  They report in either a high or low beep corresponding to the ID number- 1-4 beeps.  Condition is "Used" but this set appears not to have been deployed, the geophone spike holders are not cracked but suggest planning for them to break. This is a known fragile part on these units.  Includes original canvas bag.  I have a dozen of these sets I will be listing.  I have seen these in use with the broken clips modified with  a section of hose which work better.   These are a 'go anywhere' alarm and will last months buried in the ground.  I've seen them used as vehicle and out building alarms too.  I know these seem priced high but as I am finding as I go through the ones I have; a full working set in perfect shape are hard to find.  Military spec and built to last.  Secure your perimeter.  Please ask any questions before bidding, no international shipping.  Shipped with USPS Priority Mail Medium Flat Rate Box.  PayPal accepted.  Thanks for looking.