TM  1-1520-240-10            3-2-15 (2) Several beeps will be heard in the headset. This means that the old CNV is being replaced by a new CNV.. (3) Using this new CNV, the net controller will ask for a radio check. (4) After the radio check is completed, the net controller instructions  will be to resume normal commu- nications. No action should be taken until the net control- ler requests a radio check. d.  Manual remote keying procedures. The net con- troller will make contact on a secure voice channel with instructions  to  stand  by  for  a  new  CNV  by  a  manual remote keying (MK) action. Upon instructions from the net controller: (1) Set the FILL switch to position 6. Notify the net controller by radio and stand by. (2) When notified by the net controller, set the MODE  switch  to  RV  (receive  variable).  Notify  the  net controller and stand by. (3) When notified by the net controller, set the FILL switch to any storage position selected to receive the new CNV (may be unused or contain the variable being replaced). Notify the net controller and stand by. NOTE When performing step (3), the storage posi- tion (1 through 6) selected to receive the new CNV  may  be  unused  or  it  may  contain  the variable which is being replaced. (4) Upon instructions from the net controller: (a) Listen for the beep on your headset. (b) Wait two seconds. (c) Set the MODE switch to OP. (d) Confirm. (5) If the MK operation was successful, the net controller will now contact you via the CNV. (6) If the MK operation was not successful, the net controller will contact you via clear voice (plain) trans- mission, with instructions to set your FILL selector switch to position 6 and stand by while the MK operations re- peated. e.  It  is  important  to  be  familiar  with  certain  KY-58 audio tones. Some tones indicate normal operation while others indicate equipment malfunction. These tones are heard only in the cipher mode and are: (1) Continuous    beeping,    with    background noise, is a crypto alarm. This occurs when power is first applied to the KY-58 or when the KY-58 is zeroized. This beeping is part of normal KY-58 operation but must be cleared  by  momentarily  keying  the  No.1  VHF  AM/FM Radio before communications can be achieved. (2) Background noise indicates that the KY-58 is working properly. This noise should occur at power on of the KY-58 and when the KY-58 is generating a crypto- variable. If the background noise is not heard at power on, the equipment must be checked out by maintenance personnel. (3) Continuous  tone  should  indicate  a  parity alarm. This will occur whenever an empty storage regis- ter is selected while holding the PTT button in. This tone can mean any of three conditions: (a) Selection of an empty storage register. (b) A bad cryptovariable is present. (c) Equipment   failure   has   occurred.   To clear  this  tone,  follow  the  loading  procedures  in  TM 11-5810-262 -OP. If this tone continues, have the equip- ment checked out by maintenance personnel. (4) Continuous tone could also indicate a crypto alarm. If this tone occurs at any other time other than in (3) above, equipment failure may have occurred. To clear this    tone,    repeat    the    loading    procedures    in    TM 11-5810-262 -OP. If this tone continues, have the equip- ment checked out by maintenance personnel. (5) Single    beep,    when    DELAY    switch    is down(not  selected),  can  indicate  any  of  three  normal conditions. (a) Each  time  the  PTT  button  is  pressed when the KY-58 is in C (cipher) and a filled storage regis- ter  is  selected,  this  tone  will  be  heard.  Normal  use (speaking) of the KY-58 is possible. (b) When  the  KY-58  has  successfully  re- ceived a cryptovariable, this tone indicates that a good cryptovariable is present in the selected register. (c) When you begin to receive a transmis- sion, this tone indicates that the received signal is in a secure voice. (6) A single beep, when the DELAY switch is up (time delay) occurring after the preamble is sent, indi- cates you may begin speaking. (7) A single beep, followed by a burst of noise and a seemingly dead condition, indicates that your re- ceiver is on a different variable than the distant transmit- ter. If this tone occurs when in C/RAD1: Turn FILL switch to the CNV, Plain-Cipher switch to PLAIN and contact the transmitter in clear text and agree to meet on a particular variable.