The DSP has been altered to include up to two tones, with or without voice, for FM transmission. There are new DSP commands to control these, but this discussion relates only to the implementation of these tone functions in UHFA.EXE, the PC control program. There is also a special "Apollo-style" SSB end-beep in SSB.

Tone transmission is controlled by a dialog box, brought up as SCRL-F7. This same dialog box deals with FM and SSB tones. For FM, two radio buttons select between DTMF and FM Tone (CTCSS or start beep). The DSP can generate only two tones, so DTMF on top of CTCSS is not currently possible. If the DTMF button is selected, the level is set a few lines down, under "Level (0,100)." The other boxes "Tone Freq" and "Duration " do not apply for DTMF. DTMF is the full 16 keys: 0 to 9, A to D (or a to d), * and #. In FM with DTMF selected from the dialog box, the tone pairs will track any of these keys.

For FM, the radio button for "FM Tone" covers both CTCSS and a start beep. The tone frequency is entered in Hz, and is accurate to a fraction of a Hz. For CTCSS, enter a duration of 9999 milliseconds (the maximum allowed) and the tone will be left on continuously. I compared the level against a Yaesu HT and a level somewhere around 90 agreed with that radio. This level is in dB.

For FM, with the "FM Tone" selected, a start tone can be created by setting a duration less than 9999. A half-second 1700 Hz beep would be a duration of 500 milliseconds. All FM tone frequencies and levels are displayed above the frequency readout, when they are being transmitted.

For DTMF, two lines are displayed. This is cleared when the tone is not being transmitted.

For SSB, there is a check box to enable an ending tone. This can have the frequency, duration and level set, again in Hz, milliseconds, and relative dB. The SSB end beep is independent of the FM tone functions, as indicated by the dividing line. The beep can optionally (from the dialog box) come from the speaker, the same as a CW side tone. I have tried it both ways, and like having it audible, but to each their own. The level for the side tone is still set by the CW side tone level (Scrl S, D). The SSB frequency and level is not displayed, as it was for FM.

For SSB, the parameters apply to all VFO and memory channels. The settings are saved in the configuration file as beep_use (0 or 1), beep_freq, beep_dur and beep_level. Normally these would be altered from the dialog box.

For FM, the settings are unique for each VFO or Memory. This allows different CTCSS or start tones for each. If you save a memory (ALT-N or n), the current FM tone selections are saved. Bringing back a memory (CTRL-N or n) will bring these back. A slight caution: this is an expansion of the old VFO definitions, and the first time you load UHFA.EXE, the tone settings may not be what you want. If using old FM VFO's or Memories, open the dialog box and check the settings and adjust them. If changes were made, and a memory was in use, re-save the memory (ALT-N or n). When you shut down, the FM tone settings for each VFO will be saved. This is true, even if the VFO has been switched to a non-FM mode.

For memories, the FM tone settings are part of the frequency and mode. In the ALT-N box, they are associated with the first check item.

As usual, the key used for the tone dialog box can be changed from the UHFA.CFG configuration file. It is the variable k_tone_box. Again, a reminder: if you want to change any key, the magic hex code for the new key can be determined by changing "startup_detail" to 1 in the configuration file. When you start the program, it will prompt you to enter any key, except "Enter" and the code will be shown on the screen. Just enter that code in the configuration file line and it will be changed. If you ever think things got messed up for a key, just delete the associated line from the configuration file and the default value will be put there when UHFA.EXE is run.

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