Description Accessories Files FAQs
Compact High Performance HF Transceiver
Blending the high performance digital frequency synthesis techniques from the FT-890 with the operating convenience and affordability of the FT-747GX, the FT-840 adds a choice of two optional remote automatic antenna tuners and a wealth of convenient functions. For compact base and mobile stations, the FT-840 set the new standard for high-performance affordable transceivers. As a first-time rig, back-up or main station transceiver, the FT-840 has the features and dependability that both beginners and seasoned operators will appreciate.
Low Noise ReceiverThe receiver section of the FT-840 includes direct feed to the first mixer, for excellent rejection of intermodulation. The careful design yields a highly sensitive receiver that is renowned for its "quiet" performance.Ease of OperationWithout the clutter and complexity of some other rigs, the FT-840's outstanding ergonomics mean you always find the button or control you need quickly. The reduced number of keys also means that there is a greater proportion of the front panel space dedicated to the display than on competing rigs.IF ShiftTo help reduce interference on SSB or CW, the IF Shift feature allows you to move the center frequency of the passband around, rolling off interference from either the high or low side. Once a feature only found on top of the line transceivers, it's here for you on the FT-840!Direct Digital Synthesis (DDS)The lightning-fast DDS system provides instant lock time for the synthesizer, along with ultra-fine tuning steps, for silky-smooth tuning similar to that found on older analog VFOs.Computer Control CapabilityThe FT-840 supports Yaesu's CAT System for computer control. Use your favorite logging program to read your current operating frequency, or send frequency commands based on "spots" from your local packet cluster.
Model Antennas FC-10 Automatic Antenna Tuner FC-800 Automatic Antenna Tuner Brackets MMB-20 Mobile Mounting Bracket Filters YF-112A 6 kHz AM Filter YF-112C 500 Hz CW Filter Headsets YH-77STA Lightweight Stereo Headset for use with HF transcievers Microphones MD-100A8X Desktop Microphone MD-200A8X Desktop Microphone MH-31B8 Hand Microphone Miscellaneous DVS-2 Digital Voice Recording Module FIF-232C CAT System Computer Interface FM-747 FM Unit TCXO-4 Temperature Compensated Crystal Oscillator (+ 2.0 ppm) Power Supplies FP-1030A 30A Power Supply 110V Speakers SP-6 External Speaker
Amateur Radio \ Brochures \ Rotators
FT-840.pdf ( 1.70 MB )
What is "IF Shift" and how does it help my operation? If Shift is an advanced design that allows you to move the receiver filtering center frequency toward a lower or higher pitch. This lets you roll off interference from either the high side or low side of where you currently are operating, without changing the pitch of the incoming signal. My radio is locked in "Transmit." What is going on?
Look in the upper right-hand corner of the front panel; you'll notice a slightly obscure switch called "MOX." This switch manually activates the transmitter, and it is very easy to bump this switch by accident. Press it so as to release it outward, and you shoud switch back to receive.
If that still doesn't work, and you're using a desk microphone, disconnect the microphone. If the receiver becomes active, check the switches on the microphone; one of them is depressed so as to lock the transmitter on.
When would I use "Split" operation? I see a key on the front panel that enables Split; what does it do? On some bands, like 7 MHz, operators outside North America must transmit (on LSB) below 7.1 MHz; they have no allocation between 7.1 MHz and 7.3 MHz. So to make a phone QSO with the United States, they transmit, say, on 7075 kHz, and announce that they are listening on some higher frequency (above 7150 kHz) like 7205 kHz. You set up one VFO on 7075 kHz, and the other on 7205 kHz, then press [SPLIT]. But be careful: if you transmit whiloe [SPLIT] is engaged, and you transmit while listening to U.S. stations, you will be transmitting outside the U.S. allocation! Be sure to press [SPLIT] to go back to normal operation (TX and RX on the same frequency). I have a desk microphone on a boom in my station. Can I connect a foot switch to the FT-840 to activate the transmitter?
Yes. There is a "PTT" (Push to Talk) jack on the rear panel. It's an RCA type, and shorting the center pin to ground, via a foot switch, will activate the transmitter.
Do not use the PTT jack to control a linear amplifier, though, even though the amplifier may have a "PTT" jack on its rear panel. Use Pin 2 of the Band Data jack for control of a linear amplifier; it closes to Ground (Pin 3) on transmit, which is what the amplifier needs to cause it to go into the "transmit" condition.
My FT-840 seems to be tuning faster than I like. Is there any way to slow down the tuning rate? Yes. Refer to page 16 of the Operating Manual, and change the position of the little switch S2003 on the bottom panel of the radio, near the front. The tuning rate may be changed between 10 kHz per revolution and 5 kHz per revolution. I see something called "CW Reverse Sideband." What is this and why would it help me?
The default "sideband" for CW operation on the FT-840 is USB. That is, if you switch between USB and CW, the signal sounds the same.
However, if you go to the 7 MHz or 3.5 MHz bands, for example, LSB is the voice mode used. And if you are talking to someone on LSB, and want or need to work the other station on CW, you need to use LSB injection on CW so as not to lose the signal (due to the sideband switch when you go to CW, which uses USB). CW-Reverse does exactly what is needed.
Also, the reverse sideband may be very helpful in eliminating interference; switching to CW-Reverse may shift annoying interference out of the passband of the receiver.
COPYRIGHT©2003-2013 Yaesu USA