These satellites operate as mailboxes ("store-and-forward"): they remember the received messages and then resend them after the scheduled time, or by a command from the Earth.

Some sources state the satellites are capable of only three months of active operation, but through coordination with others[1] they can serve for about five years.

[8] In 2018 Austrian counterintelligence authorities identified an officer of the Bundesheer, Martin M. as a Russian spy.

It had radio-communication equipment built into it so that Martin M. was able to connect to Strela-3 satellites and receive and send encrypted messages.

[9] The following observations were published in 2011: On 244.512 MHz a Strela-satellite generates a 0.5s long 'trigger pulse' every 60 seconds; the purpose is to activate ground based transmitters waiting to send a message.