Daiwa Rf Rf Speech Processor

It was the acid test for my brand new Daiwa RF-440 rf speech processor: nighttime phone operation on 75 meters. Would the RF-440 really help my low-power signal punch through the bedlam? My CQ was answered by a station in Pennsylvania. After the usual exchange of pleasantries. J asked him to evaluate the per formance of the RF-440 while I switched it in and out. The result of this mini-test? ' Without the processor, you were down in the mud; I couldn't copy anything. With the processor, I copy 90%." That was enough for me. I was hooked.

Since that first night, i have used the RF 4^0 in a variety of situations, While the results are not always as dramatic as the instance cited above, the processor has yet to disappoint me.

The RF-440 is designed to in crease "talk power'" without introducing distortion and spia!-ter. It's packaged in a very attractive all-metal enclosure that is several cuts above the cheap-ooking boxes used by some accessory manufacturers. The small size (6" x 2ViM x 6") of the unit and the smooth feel of the controls give the RF-440 the aura of a precision watch. It's solid.

The RF-440 simply installs between your microphone and transceiver. It comes pre-wired for Kenwood equipment, so I had to swap connectors to use it with my Heathkit gear. The processor has an internal ac power supply, but it also operates from 12 V dc for mobile use.

Using the RF-440 is a pleasure. Simply set the gain control for a proper level using the built-in meter, then adjust the output control so as no! to overdrive your rig, I adjusted the output control using an oscilloscope, then went on the air and was told that my signal sounded fine, with no distortion. Alternatively, you could start with the control set at its midpoint, then solicit on-the-air opinions for a final adjustment.

One schooi of thought says that speech processor controls should be Inside the case so you can set them and forget them. As a confirmed knob-twiddler, I was pleased to see the controls of the RF-440 right there on the front panel where they belong. This really simplifies matters if you intend to use the processor with more than one microphone or rig. Another convenience is an "OFF" position on I he gain control which bypasses the processor for straight-through operation.

The impressive Daiwa product line is being distributed in the USA by the J. W. Miiler Division of Belt industries, PO Box 58251 Compton CA 90224. Reader service number B47.

Jeff DeTray WB8BTH/1 Assistant Publisher

Mfj Speech Processor Schematic

Daiwa 's RF-440 speech processor,

Tree's Deluxe CMOS Electronic Keyer.

Daiwa 's RF-440 speech processor,

// »//J-; J j tt I M H t it i un, f ; É ft ttt tttttmttti* ft I it f m it I run 11

Sabtfonics' model 201 OA.

// »//J-; J j tt I M H t it i un, f ; É ft ttt tttttmttti* ft I it f m it I run 11

tmuumw tuiiMtumtt

Sabtfonics' model 201 OA.

Yaesu's new FT-101ZD.

Was this article helpful?

+2 -2


  • Michael
    How to use daiwa keyer?
    2 years ago

Post a comment