FR2326134A7 - Detector for hidden miniature radio transmitters - transmits signal to microphone connected to transmitter - Google Patents

Detector for hidden miniature radio transmitters - transmits signal to microphone connected to transmitter

Info

Publication number
FR2326134A7
FR2326134A7 FR7401102A FR7401102A FR2326134A7 FR 2326134 A7 FR2326134 A7 FR 2326134A7 FR 7401102 A FR7401102 A FR 7401102A FR 7401102 A FR7401102 A FR 7401102A FR 2326134 A7 FR2326134 A7 FR 2326134A7
Authority
FR
France
Prior art keywords
detector
filter
hidden
transmitter
generator
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
FR7401102A
Other languages
French (fr)
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
RISBERG STURE
Original Assignee
RISBERG STURE
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by RISBERG STURE filed Critical RISBERG STURE
Priority to FR7401102A priority Critical patent/FR2326134A7/en
Application granted granted Critical
Publication of FR2326134A7 publication Critical patent/FR2326134A7/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03J—TUNING RESONANT CIRCUITS; SELECTING RESONANT CIRCUITS
    • H03J7/00—Automatic frequency control; Automatic scanning over a band of frequencies
    • H03J7/18—Automatic scanning over a band of frequencies
    • H03J7/32—Automatic scanning over a band of frequencies with simultaneous display of received frequencies, e.g. panoramic receivers

Landscapes

  • Circuits Of Receivers In General (AREA)

Abstract

The detector has an audio-frequency generator, a loudspeaker and a radio receiver with wide-band tuning. The receiver has an l.f. stage with a filter whose resonance curve allows the passage of signals at the same frequency as the generator. An indicator displays the signals passing through the filter. Pref. a pulse duration discriminator between filter and indicator allows the passage only of pulses having a longer duration than those produced by ordinary conversation or music and transmitted by the filter. The generator may be designed to produce signals at two or more different frequencies.
FR7401102A 1974-01-14 1974-01-14 Detector for hidden miniature radio transmitters - transmits signal to microphone connected to transmitter Expired FR2326134A7 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
FR7401102A FR2326134A7 (en) 1974-01-14 1974-01-14 Detector for hidden miniature radio transmitters - transmits signal to microphone connected to transmitter

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR7401102A FR2326134A7 (en) 1974-01-14 1974-01-14 Detector for hidden miniature radio transmitters - transmits signal to microphone connected to transmitter

Publications (1)

Publication Number Publication Date
FR2326134A7 true FR2326134A7 (en) 1977-04-22

Family

ID=9133420

Family Applications (1)

Application Number Title Priority Date Filing Date
FR7401102A Expired FR2326134A7 (en) 1974-01-14 1974-01-14 Detector for hidden miniature radio transmitters - transmits signal to microphone connected to transmitter

Country Status (1)

Country Link
FR (1) FR2326134A7 (en)

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