FT-450D Procedure for Adjusting Transmit Audio EQ, Gain and Compression

Also “Secret Menu” short cuts for Keyer Speed, Spot Tone, CW Breakin, Display Brightness

The FT-450D is still a viable choice as a beginner's radio (if it can be bought at an attractive price), and can even be fun for a seasoned operator, especially for POTA, Field Day, or portable use. It delivers reasonable performance, even with the the 1 uV sensitivity limitation. Urban environments often are so noisy that better specs than that will not be usable. I do not recommend the earlier version, which may not contain the antenna tuner or DSP (which were accessories at the time.) It is a discontinued model.

The main menu is accessed by pressing the F button, and the manual has an excellent summary of functions on pages 78 – 85. This document brings together in one spot some of the other functions scattered throughout the manual, which are not so easy to find. Some of these are shortcuts to the main menu.

TRANSMIT EQ AND MIKE GAIN

These are recommended settings for SSB while operating the FT-450D without an amplifier, and possibly a less than optimum antenna, for best communications punch.

If using the stock MH-31 hand mike, check the switch on the back of the mike. Be sure it is set to 2.

This cuts excessive low frequencies. (Position 1 is flat. See page 9 of the manual.)

Similar settings exist on the accessory MD-100 mike, which sounds very good on the FT-450D.

Adjust the Transmit Mike Equalizer for best punch. See page 40 of the manual. First make sure that the DSP/SEL button is not being used for something else. There should be no > arrows showing to the left of the RX audio functions on the left of the display. Keep pressing the DSP/SEL until the > arrow moves to the bottom and disappears. The transmit audio EQ is also accessible by pushing the F button for the general menu, but it still needs this step first.)

Now, press and HOLD for 1 second the DSP button on the left of the radio. Then press the DSP/SEL knob. This pops up a “frequency response” display at the right hand side. When the lines are all a flat line, there Is no equalization. Select a response curve that peaks the highs. I also recommend cutting the lows a bit for more punch from a barefoot 100 watt signal with a compromised antenna. In this case, I recommend a setting of 9 or 4.

NOTE: For AM operation, you may want to try an EQ setting of 4. This does not cut the lows; the 9 setting does, which is better for SSB. The FT-450D will deliver a “communications quality” AM signal equal to some unmodified vintage AM rigs, but it cannot deliver “Hi Fi” broadcast audio.

Press and hold the F button to exit this menu and save the settings.

Press and hold the F button again. Rotate the DSP/SEL knob one step clockwise to get MIC GAIN.

Now Adjust the MIKE GAIN (which also affects the compression). See page 39. Excessive gain may cause a muffled sound also. Not enough gain can cause a weak signal and not enough ALC action. Speak normally into the mike (using a dummy load or a clear frequency) and observe the ALC meter. The ALC should kick up to about S9, but not be stuck near the top or bottom of that range. For the stock MH-31 hand mike, the setting should be NOR. Low turns off the compression, but may help in noisy environments. NOR delivers more punch due to the compressor is switched on. High may result in a muffled sound. While it may yield larger average power output readings, it probably will not help your readability over the air. Use this only for lower gain accessory mikes. (The Yaesu FT-450D PWR meter reads average power, not peak power.) It also makes background noise worse.

The HEIL mike cable adapters can be used to try other mikes, but you probably will not benefit from a different mike, because the transmit bandpass filter and transmit audio circuits will not pass “Hi Fi” wide band audio. It is designed to optimize SSB transmission.

Press and hold the F button to exit this menu and save the settings.

To listen to the results of changes, use the monitor feature and a good pair of headphones. See page 42 and page 16 of the manual. It requires the assignment of the CS/VOICE function to monitor mode. I find that setting the CS button to SWR is more useful for adjusting an external antenna tuner than the monitor function.

OTHER USEFUL MENU SHORT CUTS

Press and hold the IPO button for a spot tone for CW.

Press and hold the KEYER button to set CW transmit keying speed.

Press and hold the CLAR button to clear the clarifier offset.

Press and hold the AGC button to turn AGC off. Use the RF gain control to prevent overload.

Press F then VOX to set for CW break in operation.