Yaesu Ft Hf Transceiver

Checked any equipment prices lately? When it comes to equipment, hams have never been able to get so much quality and performance lor so little money. The new Yaesu FT-707 HF transceiver Is a good exampie. It offers features and performance equal or superior to top-dollar rigs of a few years ago. Today1 the FT-707 is one of Yaesu's least expensive rigs, it says a lot for the state of the art when a relatively inexpensive transceiver offers the features this new Yaesu does. Let's take a good took at it.

The FT-707 is similar in size to rigs like the Kenwood T5-120S, the Icom 10701, and the Atlas 150, It covers ait present and planned bands between 80 and

10 meters, Including the new WARC bands. The bandswitch itself has a very precise feel, cflcking smoothly into place, rather than thunking noisily as do bandswitches on many other rigs. Just to the right of the bandswitch is the vfo knob which also seems to have been engineered for the proper feel.

YesT the 707 has the digital frequency readout that ^e now take for granted on high quality gear, but it aiso offers a well-calibrated and easy-to-read analog display, useful when the companion external vfo and memory unit is in use, Just above the vfo knob are four status LEDs, telling which vfo is in use. if the marker generator is switched on or off, and whether a crystal-controlled frequency has been selected.

Yaesu 7070m
The Yaesu 707 line.

The display that attracts the most attention Is the front-panel meter, which Is a multi segment bar-type LED display. The lower-value segments glow green, higher readings are yellow, and the highest readings show red. This display does more than impress your friends. It allows you to keep tabs on signal strength, relative power output, and ale level

Whether LED displays are really better than regular meters has been a subject of much debate lately For the purposes It serves on the 707+ the LED display works admirably, particu-lary in mobile installations where a traditional meter would be difficult to read while maintaining safe operation of a vehicle.

Other goodies on the front panel include an effective noise blanker, an i-f shift control a 25*kHz marker generator, VOX controls, an RIT control, and an eight-conductor microphone plug that permits scanning from the mike If the rig is equipped with the FV-7070M external vfo, Also worth mentioning are the rf gain control, fast/slow age switch, and fixed-channel operation switch. Along with the usuai antenna, key, and power connectorst the rear panel sports an rf output jack for use with transverters, and sockets for the external vfo and accessories. Yaesu has managed to squeeze a tot into a small packagel


Unpacking a new rig and wiring It into the ham station is an activity that most hams enjoy, and the hams at 73 are no exception! We had the 707 and its ac* cessories wired to ground, power, and our Alpha 374 amplifier in no time at all. The human engineering that went Into this rig is obvious; few other rigs we've seen have interfaced with such easa Like the Icom 701, this rig has a relay box that is necessary if you plan to use both an amplifier and the external vfo. Even if you will only use an amplifier, this accessory is worth purchasing; it makes interfacing much simpler.

As soon as the rig was in place, the manual read, and basic operating parameters checked, we put the rig through the infamous 73 wringer, We connected the 707 to our Drake OL-IOOO dummy load and checked the power output m the CW mode, A Bird wattmeter confirmed YaesuHs claim of full output on all bands, Our sample put out 100 Watts ±10%, with highest output on 80 and 20 meters, and lowest on 40 and 10 meters. Several other rigs we have tested have dropped by as much as 50% on 10 meters. The Yaesu's performance is admirable.

While we had the 707 on the dummy load, we checked out Yaesu's protection circuits Like most of its solid-state brethren, the FT-707 finals are protected with a high swr shutdown device. As the swr climbs, the riig automatically reduces power to protect itself. Many rigs carry this to a fault, and almost any swr at all on the line causes a significant reduction in power output.

Yaesu's engineers seem well acquainted with the real world, and they designed the 707 to shut down only slightly at 2:1 or tower. Limiting action is heavy at 3:1 or higher, shutting the output down to a small percentage of its capabilities. This is a sensible arrangement, since many hams operate their equipment into transmission lines with moderate standing wave ratios. Further, a defect in the feedllne or an improperly set coax switch will probably cause the swr to go much higher than 2:1. In short, the FT-707's ability to pro* tect its expensive output devices Is hardly curtailed, yet the annoying side effects of such protection have been mercifully banished.

Other protection circuits include a temperature-controlled fan and a thermal shutdown circuit. The instruction manual recommends a key-down period of no longer than 30 seconds, but we wanted to see how well the 707 protects itself, so we left il key-down ior several minutes. Sure enough, the fan came on after a minute or so. and continued to run after switching over to receive. Having the fan run until the finals cool off is an excellent idea. Unfortunately, our unit was cursed with a noisy fan which rattled In a most aggravating manner. This was a problem peculiar to our sample, and it shouldn't be encountered in other 707s*

During normal operation the fan never came on at all, confirming that the fan is only a safety feature; the rig has

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