The Yaesu FT-100 and ATAS-100

Is it fit to be called a Field Commander?

-by John Aceti, N1GMV


Vehicle as shown: 40-440!

Back in the early 70’s I noticed a Full size station wagon pull into a gas station with a gigantic antenna. Since I was interested in communications equipment I just had to take a sneak peak as what was set in this thing.  To my amazement I noticed a Full Sized Yaesu 101 mounted under the dash. Wow! This was NOT your typical two way installation!  He mentioned that he was able to work all over the world with 100 watts from his mobile which brings me now to write this article.


Years have gone by since that day and I have installed quite a few mobile radios in different vehicles. They were all the same in one aspect. They would all require me to stop, open the trunk, find the right coil and replace the existing one on my antenna mast when changing bands. It didn’t matter what band I was set for, seemed  I always wanted to go to another! 


Now, thanks to the wonderful invention of the “Screwdriver” antenna, coil changes are becoming a thing of the past. No longer do you need to do the “Coil Shuffle” in order to switch bands.  Unfortunately, these antennas are quite large and raise an eyebrow or two when pulling up to your local supermarket. Basically these are way too big!


Lets face it, today we don’t have the room under our dashboards to mount a FT101 nor do we want to have a street trolley sized pole trolling the skyline!


The 2 main options if we want one small radio for HF/VHF/UHF:


Our Options if we want an HF antenna:


I chose the FT-100 primarily because of its integration with the YAESU ATAS-100 (Active Tuned Antenna System) providing HF through 440 coverage with nothing more than that a push of a button! The ATAS-100, a 5 foot antenna works from 40 Meters to 6 Meters and when fully retracted works (somewhat) on 2 and 440. Below is an analysis of my FT-100/ATAS-100 installation.


Power: The rig is supposed to be 100 watts. When operating, the internal meter peaks at 100 watts on HF however, I only read an average of 50 watts on my peak reading MFJ meter. This same meter shows 80 watts with my IC-735. Has anyone seen my other 50 watts anywhere?


Hot!: The unit gets unusually hot when running full output on 2 meter FM. All other bands and modes seem fine. I suppose the mounting bracket will help sink some of this heat from the unit.


Operation: Menu’s Menu’s and more Menu’s!, Can I get HBO here? (9 main menu’s, 66 sub menu’s and function keys which have dual function!) Don’t let this scare you though, I found that after a contest weekend I was able to be quite proficient with the menus, only referring to the book once or twice. Maybe I will offer Yaesu FT100 Certification Classes!


Cool Functions: Such as Talk out Timer (Repeater pre-timeout warning), Auto Power Off (No need to call AAA for a jumpstart) and Digital Signal Processing- way KEWL! I might add that this radio comes with a DTMF microphone unlike the ICOM in the event you wish to use an autopatch!


Boo for Blue: Now you see it,                         Now you don’t!



Yes, the radio is ON in both these pictures, the only thing changed is the position of my vehicle! Keep this in mind before mounting the head. Do NOT mount it high on the dash! Also, the display is more visible at an angle than looking directly at it.  This position was best for me since it allows me to rest my wrist on the shifter and arm on the console when turning the VFO. Holding your arm straight out turning a VFO when driving is no fun. You can use the up/down buttons on the microphone if you like but I prefer to use the VFO.


The ATAS-100: Up n Down!


Tuned to 7.255 MHz                                        Tuned to 53.030 MHz

Tune to the frequency, press TUNE momentarily, the radio and antenna will do the rest!

The radio transmits a low output carrier while it sends dc pulses to the ATAS-100. Once the SWR falls into spec, the radio switches back to receive mode. I have had no problems with SWR on any band including the WARC bands with this antenna. I give this antenna a 9!  The antenna requires an SO-239 mount. Get a heavy duty one! I used the one from Comet, which came complete with its instructions that I cannot read. Anyone here speak Japanese?  If you use a diplexer you may use the ATAS-100 for HF/6 and VHF/UHF. I tested this antenna on VHF and UHF, the SWR was great but the signals were very low (2-3  S units lower) in comparison to my Diamond 7500 NMO as shown. So, I decided to use it for only 40-6 meters and keep the Diamond for use on the high bands.



Mounting the Radio: This radio is so small you can mount it almost anywhere. I chose to mount mine in the trunk so had to order the separation kit to extend the speaker, microphone and front display. This kit also included the mounting bracket for the head. Velcro will NOT hold this head in the summer heat so be prepared to drill or use silicone. When mounting the unit in the trunk be sure to mount the front facing the opening, this will allow you to mount the faceplate on the rig for troubleshooting or remote operation. Power MUST come from the battery. Be sure to fuse both ends of the power lead and install a 35 Volt MOV across the positive and ground just before the radio. Spikes from starting the vehicle will cause this unit to change frequencies!



FT-100 Specifications:

   Frequency coverage:
RX :100 kHz - 970 MHZ
(Cellular/digital telephone frequencies are temporarily blocked)
TX :160-6 m 144-148 MHz 430-450 MHZ (all modes on all bands)
Power output: 100W (160-6 m), 50W (144 MHz), 20W (430 MHz!)
DSP BandPass Filter, Notch Filter and Noise Reduction (all adjustable)
IF Noise Blanker (adjustable)
IF Shift
SSB, CW, AM, FM, AFSK, Packet (1200/9600 bps) operation
Two Antenna Pigtails (HF/50 and 144/430)
Dual VFO
Available IF bandwidths of 6 kHz, 2.4 kHz, 500 Hz, and 300 Hz
(6 KHz, 500 Hz, 300 Hz filters optional)
Built-in Electronic Memory Keyer
Built-in CTCSS and DCS for FM operation
Automatic Repeater Shift and Auto-Range Transponder System
Smart SearchTM Automatic Memory Channel Loading System
300+ Memory Channels
Quick Memory Bank (QMB)
Blue LCD multi-function display
Compatible with ATAS-100 Active-Tuning Antenna System

   And Much more…




In final,  I would say that this radio setup performs quite well. Is it worthy of being called a Field Commander? NO WAY, not with only 100 watts! Then again, I am driving a Monte Carlo not a Hummer!  Just like anything else there are always a few pitfalls. Overall, I would buy another one over the ICOM 706. And in the event I ever work someone running a 706? It’s okay, I will wait for them while they change bands!