TRANSCEIVER WITH TIME DIVISION MEANS FOR INDICATING THE PRESENCE OF AN EMERGENCY CHANNEL SIGNAL WHILE RECEIVING INFORMATION ON A NORMAL CHANNEL

• US 3,832,636 A
• Filed: 11/02/1972
• Issued: 08/27/1974
• Est. Priority Date: 11/02/1972
• Status: Expired due to Term

• Current Assignee: Mutsuo Kubo
• Original Assignee: Mutsuo Kubo
• Inventors: Kubo, Mutsuo
• Primary Examiner(s): Mayer, Albert J.
• Application Number:
  US05/303,023
• Time in Patent Office: 663 Days
• Field of Search: 325/15,64,466,364,492,21,22,25,468,470,472 343/180,181 179/15BF 340/413
• US Class Current: 370/430
• CPC Class Codes: G08G 1/093 Data selection, e.g. prioritizing information, managing message queues, selecting the information to be output
• CPC Class Codes: H03G 3/341 Muting when no signals or only weak signals are present H03G3/344, H03G3/345 take precedence
• CPC Class Codes: H03J 5/246 using electronic means H03J5/244 takes precedence
• CPC Class Codes: H03J 7/18 Automatic scanning over a band of frequencies
• CPC Class Codes: H04B 1/40 Circuits

Abstract

A transceiver includes a time division receiving system which shares reception between a normal channel and an emergency channel. The normal channel is shared for a sufficient time to minimize loss of normal channel signal information while providing means for indicating reception of a signal on the emergency channel and displaying the reception by means of an indicator.

Claims

1. A receiver for receiving signals on a plurality of different frequency channels which include an emergency channel and a normal channel, which comprises:

means for generating a signal corresponding in frequency to the channel desired to be received;

means for tuning said generating means to said desired frequency;

means connected to said tuning means for causing said tuning means to be tuned to a frequency corresponding to the frequency of said emergency channel for a preselected time period which is small compared with the time said tuning means is tuned to said normal channel; and

means for indicating the presence of a received signal on said emergency channel while said receiver is receiving information on said normal channel.

2. A receiver for receiving signals on a plurality of different frequency channels which include an emergency channel and a normal channel, which comprises:

first switch means for selecting a normal channel desired to be received, means responsive to said first selecting means for generating a signal corresponding in frequency to the frequency of said desired normal channel;

control means connected to said generating means for causing said generating means to periodically generate a signal corresponding in frequency to the frequency of said emergency channel while said first selecting means is switched to said normal channel; and

means for indicating the reception of a signal on said emergency channel while said first selecting means is switched to said normal channel whereby the operator of said receiver may be advised of the presence of an emergency signal on said emergency channel while still receiving information on said normal channel.

3. The receiver according to claim 2, wherein said control means comprises means for gating said generating means to allow said normal channel signal to be generated for a time period substantially longer than the time period of generation of said emergency channel signal.

4. The receiver according to claim 3 wherein said gating means includes means for establishing said time period of generation of said normal channel signal to be approximately 90 percent of the total '"'"''"'"''"'"''"'"'ON'"'"''"'"''"'"''"'"' time of said receiver.

5. A transceiver having a plurality of different frequency channels which include an emergency channel and a normal channel, which comprises:

a transmitter for transmitting information-bearing signals, a receiver for receiving information-bearing signals;

means for switching said transceiver from its transmitting mode to its receiving mode;

said receiver including;

first switch means for selecting a normal channel desired to be received, means responsive to said first selecting means for generating a signal corresponding in frequency to the frequency of said desired normal channel;

control means connected to said generating means for causing said generating means to periodically generate a signal corresponding in frequency to the frequency of said emergency channel while said first selecting means is switched to said normal channel; and

means for indicating the reception of a signal on said emergency channel while said first selecting means is switched to said normal channel whereby the operator of said receiver may be advised of the presence of an emergency signal on said emergency channel while still receiving information on said normal channel.

6. The transceiver according to claim 5 further including means for supressing a burst signal received on said emergency channel while said switching means is switched from said receiving mode to said transmitting mode.

7. The transceiver according to claim 6 further comprising second switch means for selecting said emergency channel to be received after said indicating means indicates the presence of said emergency channel signal.

8. The transceiver according to claim 5 further comprising squelch control means for nullifying received signals having a magnitude below a predetermined level.

9. The transceiver according to claim 5 wherein said receiver further comprises means for automatically locking said generating means to the frequency of said emergency channel in response to the indication by said indicating means of the presence of a received signal on said emergency channel.

10. The transceiver according to claim 9 wherein said automatic locking means further includes means for inhibiting the operation of said control means in response to the reception of a signal corresponding in frequency to the frequency of said desired normal channel whereby said generating means becomes locked to said frequency of said normal channel.

11. The receiver according to claim 2 further comprising means for automatically locking said generating means to the frequency of said emergency channel in response to the indication by said indicating means of the presence of a received signal on said emergency channel.

12. The receiver according to claim 11 wherein said automatic locking means further includes means for inhibiting the operation of said control means in response to the reception of a signal corresponding in frequency to the frequency of said desired normal channel whereby said generating means becomes locked to said frequency of said normal channel.