Yaesu FT-991 Features

The Yaesu FT-991 Transceiver is capable of operating SSB, CW, AM, FM, Packet and System Fusion C4FMDigital. The legendary tradition of Yaesu design is a legacy of excellence established decades ago, providing quality, stability and durability.

The Yaesu FT-991 is designed for the most competitive operating situations, with a suite of new features to’enhance the experience. Whether you primarily operate at home, mobile or in the field, the FT-991 will provide outstanding fundamental performance and an inviting expansion into a full featured base station.

^{Radio Features;}

• ^{160 Meters through 70 Centimeters – SSB/CW/FM/C4FM Digital/AM/RTTY/PSK}
• ^{100 Watts (2 Meter / 70 Centimeter: 50 Watts) of Solid Performance}
• ^{3.5 inch TFT Full-Color Touch Panel Operation for Superior Operability and Visibility}
• ^{High Speed Spectrum Scope with ASC (Automatic Spectrum-Scope Control) built-in}
• ^{Roofing Filter 3 kHz and 15 kHz}
• ^{High Accuracy TCXO ±0.5 ppm and high resolution DDS and PLL local oscillator}
• ^{32-bit High Speed Floating Point IF DSP}
• ^{IF WIDTH and IF SHIFT provides great QRM Rejection}
• ^{CONTOUR, DNR, IF Notch and APF (Audio Peak Filter, CW only)} 

• 160 - Meters High Speed Automatic Antenna Tuner included 

Yaesu FT-991 Review

This is my second update to my original review. I've owned an FT-991 for two months now. In my first update I mentioned that I thought there was some receive audio distortion in CW modes. It turned out to be magnetically induced by my power supply. After remedying that I found the FT-991’s receive audio is excellent – as good as I’ve ever heard from a radio. I mean that in terms of communications quality (i.e. “intelligibility” vs. “studio” quality). Communications quality is the key to a good ham radio in my opinion.

I am totally satisfied with the radio so I still rate it a 5. It is an outstanding value for the money. Here is the rest of my original review:

I did update the firmware, and I loaded memories using the RT Systems software, all of which was straightforward. The USB PC/radio interface for programming, audio and control was easy to configure. Other than a bit of an initial learning curve the radio is easy to use. That said, it most definitely takes a few steps to go from chasing DX on CW on the HF bands, to scanning local repeaters on the VHF and UHF bands, primarily because it's a small radio without many buttons or knobs so a lot of things must be configured by the touch screen. Once configured, there doesn't appear to be any operation the radio can't handle. I haven't really tried the digital modes.

FT-991 Bad AM Audio Quality

The FT-991 actually has a false start. The early series of the FT-991 suffered from a failed output stage and poor audio quality for AM . It is claimed (probably wrongly) that this would set a wrong bias. However, gives the repair expert that it is very likely that there has been a bad production run of RD100HHF1-101 FETs. This allows the RF amplifier was not working properly. The consequence of a failed FET in the output stage is that the quiescent cu

Yaesu FT-991 Mars/Cap Mod Control Unit Access Instructions

Yaesu FT-991 Mars/Cap Mod Control Unit Access Instructions

This information is solely for use by licensed members of MARS (Military Affiliate Radio System) or CAP (Civil Air Patrol), and release to any other party is not authorized. Use of any Amateur Radio product outside of the Amateur band is at the users own risk, and no guarantee of compliance with specifications outside the Amateur bands is expressed or implied. The Limited Warranty does not cover damage caused by any attempt to modify an apparatus for out-of-Amateur-band operation, nor does the Limited Warranty cover damage to components that may result from out-of-Amateur- band use.

Yaesu-FT-991 Digital noise filters

I'm new to amateur radio and the Yeasu FT-991. When I try any of the 15 DNF's it sounds like people are talking from under water. Am I doing something wrong?

All digital noise filters produce some alteration to the sound; the underwater effect is a good way describe it.  The trade off is between less white nose in exchange for a more intelligible signal albeit, a little less natural sounding signal.  I suppose it's Nature's way of insuring that we don't get something for nothing!

The trick is to find the DNR setting that works best at a particular time for the particular signal.   I find with my FT-991 that a setting of only 1, 2, or maybe 3, usually works best for voice.  For CW and digital modes I find that higher settings, even up to 15, usually work well.  DNR seems to help CW and digital modes more than it does voice modes.  Sometimes, contrary to intuition perhaps, the DNR works better when the bandwidth of the receiver is made wider.  That is usually the case when there is mostly white noise, but it doesn't particularly help if widening the signal lets in more of other type noise such as splatter.  All in all I probably only employ the DNR to help my reception about 10-20% of the time.

I also have an Icom 7600 and I find that Icom and Yaesu's DNR operations differ somewhat.  Icom's DNR tends to increase in garble and decrease in noise more gradually than does Yaesu's and only helps to about half way to the maximum setting as the DNR level is increased.   Yaesu's DNR tends to increase in garble and decrease in noise more quickly but sometimes helps all the way to the maximum setting.  Both are effective at noise reduction and it just a matter of tweaking the settings to your taste at any given time.  Sometimes the effect isn't all that much and sometimes there's a very dramatic improvement when applying the DNR to a signal, it just depends on the particular signal and noise in a given situation.  Also, besides bandwidth settings, there is definitely interaction between the DNR and other interference rejection controls such as the Contour control.  The Contour control is one in particular for Yaesu radios that can help in conjunction with the DNR.

Personally I find the art of optimizing received signals using the various controls like DNR to be an intriguing aspect of the hobby.  I'm glad it isn't a perfect science!

Yaesu FT-991(A) Users Group (groups.io)
https://groups.io/g/Yaesu-FT-991

Ham Radio Deluxe and FT-991

I cant seem to get Ham Radio Deluxe (HRD) to recognize my FT-991. My computer communicates with the FT-991 fine through the USB cable for my firmware updates but when I try to start HRD it will not connect to the FT-991. 

I have tried rebooting my computer and I have tried a full factory reset on my FT-991 and thoughts or suggest will be appreciated as always.

Yaesu FT-991 - Programming the Memory Channels

Yaesu FT-991 - Programming the Memory Channels

http://youtu.be/bdQTYmwWaWI

Yaesu-FT-991-group AM Transmit Audio

Yaesu-FT-991-group AM Transmit Audio

I purchased a new FT-991 late December 2015. Everything seemed OK with the radio until I tried AM. I wanted to participate in a local 6 meter AM net. The audio is distorted to the point where no one can understand me. I tried setting the power to 5 watts into a dummy load, lowering mic gain, turning off min-EQ, all with no success. I also noted downward modulation only. And yes I did a factory reset.

I checked with 3 other people who recently purchased the 991 and they all sound horrible just like mine. I am afraid this radio design is broken on AM. Good thing I kept the boxes. Anyone else seeing (hearing) this problem?

Yaesu FT-991 review

I currently own a Yaesu FTDX-3000 and was looking for a field day/portable rig with the smallest footprint, the FT-991 was it! It was a toss up between the FT-991. Icom 7100 or wait for the new unreleased Icom 7300. I own a Yaesu Quadra amplifier so I preferred the FT-991 to keep the connections simple, the radio also has VHF/UHF and a decent frequency receive range that comes close to most scanners!

The FT-991 is not that small but it is small enough for portable use, it may not be the best choice for backpacking but I can see it being a great fit for field day, lighthouse events and dxpeditions. I installed mine in a Gator GR-4S 15in deep case using the optional mobile mounting bracket. There was plenty of room available for a switching P/S, speaker and power connectors. The whole case weight about 25lbs and could also be brought on board flights as a carry on piece of luggage.

How does the radio work? Well, on SSB the DSP is great, it blows away the FT-857 and FT-897, I also found the DSP was actually too strong even on the lowest level, the latest DSP firmware update seems to have resolved this by weakening it a little. It is still not as nice as the DSP on the FTDX-3000 but it is pretty close, for example on the FTDX-3000 my DSP on level 6 is comparable to the FT-991 DSP level 2 or 3. Most of the time I have the level set to #2 as anything higher starts to create a fishbowl effect.

Yaesu-FT-991 : 5Mhz on the 991 MARS wideband mod

Yaesu-FT-991 : 5Mhz on the 991 MARS wideband mod
Frequency Expansion Information

This information is solely for use by licensed members of MARS (Military Affiliate Radio System) or CAP (Civil Air Patrol), and release to any other party is not authorized. Use of any Amateur Radio product outside of the Amateur band is at the users own risk, and no guarantee of compliance with specifications outside the Amateur bands is expressed or implied. The Limited Warranty does not cover damage caused by any attempt to modify an apparatus for out-of-Amateur-band operation, nor does the Limited Warranty cover damage to components that may result from out-of-Amateur- band use