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The Digital Voice Recorder

8.1      Digital Voice Recorder

Figure 8‑1 shows the audio signal paths for the DVR. Your received audio, after processing by the DSP including receiver equalization (RX EQ), filtering, noise blanking and noise reduction, can be recorded by holding the AF REC key. By holding AF PLAY you can play back the received recorded audio, and you can transmit this recording as well if you tap XMIT or hold PTT.

You can record transmit messages in the two M1M4 memory banks. Recorded messages can be transmitted by tapping M1M4. When transmitting, the recorded audio is processed by the DSP (TX EQ, compression etc.) just like any other audio source.

You may monitor your transmitted audio (both DVR and microphone) as you always have or you may choose to monitor DVR audio at a monitor level different than the microphone monitor level.  See CONFIG:TX DVR Ind.



Figure 81.  Signal flow in the KDVR3 digital voice recorder.



1.       You cannot transmit and record at the same time. Transmitting takes priority over recording.

2.       If the DVR is transmitting, activating PTT or VOX will immediately stop it.  This means, for example, if you are sending a contest report using the DVR, tripping the VOX will stop the report.

3.       TX EQ and other transmit audio processing does not process audio input from your microphone or Line In when your are recording messages in the DVR.

4.       RX EQ and other received audio processing does process audio before it is recorded by the DVR.

5.       When the DVR plays back recorded audio to the speaker or headphones, no further RX EQ or other receiver audio processing is done. You hear what was recorded.

6.       Audio output from the DVR to be transmitted is processed by TX EQ and other transmit audio processing.

7.       If you transmit recorded received audio, the transmitted signal will have both received audio processing (done when recorded) and transmit audio processing.

8.       M1M4 and M1M4 cannot be used for message keys and programmable function keys simultaneously.



8.1.1      DVR Configuration

After installing the KDVR3, configure it as shown in Table 8‑1.


Table 81.  DVR configuration menu.

Config menu




Not Inst

Set to nor when the KDVR3 voice recorder option is installed. Exit and turn power off and then back on.

Tap  1  to USE PTT for manual PTT operation during message transmission. Normally the DVR asserts the PTT (AUTOPTT).




When monitoring transmit audio, you hear both DVR and microphone audio at the MON level set by MON


The DVR and microphone monitor levels may be set independently. Hold MON when DVR xx is displayed, rotate MON   to set its level. Hold MON again to display MON and set the monitor level for the microphone.



You are going to spend the weekend contesting and you have the CQ and report messages recorded in M1 and M2. How do you set up the DVR so that you hear the DVR messages when they are being transmitted but not your microphone audio?

 · · · 

Set CONFIG:TX DVR to Ind. Hold MONand set DVR to a comfortable level; hold MON again and set MON to 00.


8.1.2      Recording Messages

There are eight DVR message memories in two banks of four as shown in Figure 8‑2, similar to the eight CW message memories. Holding REC toggles between BANK 1 and BANK 2. Tapping M1M4 accesses each of the memories in the currently active bank. You may record up to 14 seconds in each memory. The remaining buffer time is displayed in the VFO B display area as you record. In addition to voice messages, when you are operating CW the eight memories are available for CW messages. Chapter 3 shows how to program these.


Figure 82. DVR message memories.


Recording the Message

The signal flow for recording a message is shown in Figure 8‑3.

1.       Hold TEST to enter test mode so you won't be transmitting while recording.

2.       While speaking into your microphone with a normal voice, adjust MIC for a peak ALC reading of about 5 bars for the proper recording level.

3.       Disable VOX or take care not to trip the VOX or you will transmit, not record.

4.       Hold REC to select BANK 1 or BANK 2.

5.       Tap REC and then tap M1M4.

6.       Record your message. The remaining time in seconds is displayed while you record. If you must use PTT to get audio from your microphone, press PTT after starting to record.

7.       Tap REC again to stop and then hold TEST to leave test mode, although it is a good idea to stay in transmit test mode until after you check your message by playing it back.



Figure 83.  Recording a message.




Playing Back a Message 

The signal flow for playing back a message is shown in Figure 8‑4

1.       Hold REC to select BANK 1 or BANK 2.

2.       Tap M1M4. Sit back and listen to your message being sent.

3.       To cancel a message after it starts, either tap REC or XMIT, activate PTT or VOX, or tap any other switch besides M1M4.


Figure 84.  Playing back a recorded message.




Message Erase

1.       Tap REC, then the M key to be erased, and then REC in quick succession.

Auto-Repeat a Message

 Hold, rather than tap, M1M4 to repeat the message in the buffer. The message repeat interval may be set to 1 to 255 seconds by the MAIN configuration menu item MSG RPT. Tapping tap REC or XMIT, activating PTT or VOX, or tapping any other switch besides M1M4 cancels the message.


Table 82.  Main menu message repeat time.

Main Menu Entry





Set this for the message repeat interval in seconds (0 to 255).





8.1.3      Recording Received Audio

You may record up to 90 seconds of received audio in a loop recorder. That is, if longer than 90 seconds is recorded, the oldest data will be recorded over. Figure 8‑5 shows how the DVR recording buffer is used when recording received audio. In Figure 8‑5(a), 45 seconds have been recorded. When played back, VFO B shows *01 – *45. The "*" indicates that this is the most recent audio clip recorded, and 01 – 45 shows where you are in the 45 second recording. In Figure 8‑5(b), another audio clip of 20 seconds is recorded. This is recorded over the first 20 seconds of the first recording. When played back, VFO B shows *01 – *20 when it is playing the 20-second recording and then 21 – 45 when it is playing what is remaining of the first recording.


Figure 85.  Received audio buffer use.


Recording the Received Audio

As shown in Figure 8‑6, the receiver's audio is processed by the receiver equalization (RX EQ) and any DSP filtering, noise blanking or noise reduction.

1.       Hold AF REC to start recording received audio. The  icon just above the right end of the S-meter will slowly flash during recording.

2.       Hold AF REC again to stop recording.


Figure 86.  Recording received audio.


Playing Back Received Recorded Audio

You can play back the recorded audio so that it is heard in the speakers and headphones. It can also be retransmitted. VFO B will display a seconds counter showing the current time in the 90 second record buffer as Figure 8‑5 shows. The playback starts at the beginning of the most recently recorded audio. An * is displayed when you are in the most recently recorded segment. See Figure 8‑5. Figure 8‑7 shows the signal flow when playing the audio buffer.

1.       Hold AF PLAY to play back the current recorded audio. The  icon just above the right end of the S-meter will flash quickly. Rotate VFO B to jump forward or backward through the audio.

2.       Stop playback by tapping any button.


Figure 87.  Playing back recorded received audio.


Transmitting Received Recorded Audio

Figure 8‑8 shows the signal flow for transmitting audio that has been recorded from the receiver.

1.       Activate PTT or tap XMIT before starting the play back.

2.       Hold AF PLAY to play back the most recently recorded audio. The  icon just above the right end of the S-meter will flash quickly. Rotate VFO B to jump forward or backward through the audio.

3.       Stop playback by tapping any button.



Figure 88.  Transmitting received recorded audio.


8.1.4      Message Memories and Programmable Function Keys

As Section 8.1.1 above describes, M1M4 and M1M4 can be used programmable function keys and macro keys. When they are, you cannot use them for message keys, but any pre-recorded messages saved for these keys can be recovered.

1.       Switch to CW mode.

2.       Tap REC.

3.       Then tap the buffer you would like to restore (M1M4).

4.       Then tap REC again.

5.       Switch back to SSB mode.

Once you have done this, M1M4 and M1M4  are restored to playing and repeating messages.


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