CH429833A - Schaltungsanordnung zur Nachrichtenübermittlung, insbesondere für Wechselsprechanlagen
- Google Patents
Schaltungsanordnung zur Nachrichtenübermittlung, insbesondere für Wechselsprechanlagen
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Publication number
CH429833A
CH429833ACH339962ACH339962ACH429833ACH 429833 ACH429833 ACH 429833ACH 339962 ACH339962 ACH 339962ACH 339962 ACH339962 ACH 339962ACH 429833 ACH429833 ACH 429833A
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Application filed by Standard Telephon & Telegraphe, Nissl & CofiledCriticalStandard Telephon & Telegraphe
Publication of CH429833ApublicationCriticalpatent/CH429833A/de
Door intercom with door-opening button - centrally generates call signal and feeds to individual internal intercoms using circuit including two series-connected Zener diodes and parallel decoupling diode