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Below is a photo of the new Yaesu/Vertex model VX1200:
See the excellent write-up on this new radio by Bonnie Crystal, KX6XA, which is included below: :
"Vertex VX-1200 : First Impressions" by Bonnie KQ6XA PREFACE For publication, please contact the author. The author is not connected with or compensated in any way by Vertex/Yaesu.WHAT IS THE VX-1200? Only 8 pounds in the pack... we're walking and talking south of the border on HF SSB with the Vertex VX-1200 using its integral 5 ft whip antenna. It's a complete 20W backpack 3~30MHz HF station in a compact rugged water-resistant package. One stop shopping for those who must have a dependable HF backpack system for real world communications purposes. At such reasonable cost, this little powerhouse is an expedition delight and joy to behold. The VX-1200 is certainly not for everybody, but is it for you? Read on... Looking more like a modern business band FM with its stealth style flat black metal and contoured lexan front, the VX-1200 kicks off a new generation of HF SSB manpacks by sporting an extremely lightweight design featuring internal 4.8Ah lithium-ion rechargeable battery pack. The deep contoured ribs of the black-on-black front reveal a subtle amber backlit LCD display, with no visible markings to give the average person any clues about the purpose of the unit or its controls. At 20W output on SSB/CW/DATA and 10W AM, with internal one-touch automatic antenna tuner, it has just the right balance of power necessary to communicate while not burning too much battery. ON THE AIR Transmit audio using the hefty waterproof MH-50B7A speaker-microphone is natural sounding, which led to "nice audio" reports during some NVIS contacts with a group of SSB stations in a 300 mile radius on a little 20ft hunk of wire. The microphone seems to sound best when talking in a normal voice about an inch away at an angle. The coiled cord is long enough to reach perfectly when the unit is backpack carried, and the metal mike clamp holds very securely to a pack strap or clothing.Even though the internal automatic antenna tuner will resonate it, the stock YHA-61 whip by itself is not a top transmit performer on the lower frequency HF bands. This simple plastic coated stainless steel whip does get through surprisingly well above 10MHz, especially after adding a 15ft wire counterpoise to the convenient front panel grounding jack. On one average propagation day, many SSB contacts with average/good signal reports were made over 3000+ mile paths on 14 to 28MHz using the YHA whip while sitting in a field. RECEIVE The receiver is very sensitive and selective, using a 2.4kHz filter, with plenty of gain to provide full audio output into the speaker or speaker-mic even when using the whip on 28MHz. Receive AGC action is fast, similar to other military manpack units, making the audio quite intelligible on both SSB and AM, but not very comfortable to listen to. When using base station antennas with greater signal strengths and noise levels on lower HF frequencies, since there is no manual RF gain or attenuator, the overall effect is an articulate but somewhat harsh and utilitarian listening experience. Intended for no-nonsense communications, this is not the kind of armchair rag-chew audio most operators would find enjoyment with. The unit receives technically well even in the presence of strong adjacent signals such as those found on 7MHz, and remains unbothered even when operated within a half mile of MF multi-kilowatt AM stations. Aside from basic noise blanking which is enabled continuously, there are none of the bells and whistles one might find on an amateur transceiver. No DSP, no variable or notch filters, just a basic sharp SSB passband with no frills. AM reception is good. Receiver/Transmitter offset on CW is programmable, and the clarifier (RIT) is sufficient for most applications, including talking cross-mode from CW to USB stations.There is no narrow passband filter and CW receive is in the USB mode only. Vertex has included a special type of squelch system with programmable weight and delay characteristics. The squelch can be programmed to trip when a consistent station is received, while rejecting some other types of noise. Also, there is an option for various standard selective calling or "SelCall" method, which are software programmable, compatible with other brands of commercial HF gear. The power-saving mode reduces current down to about 100mA while waiting for a SelCall signal or squelch break. FEATURES AND CONTROLS The bolted and gasketed front panel is the heart of the entire unit. The speaker hides behind slits in the textured black lines. The front panel has following objects: 1 SO-239 connector (ANT- high strength) The Volume and Clarifier knobs are straightforward, but the Select knob has three functions. In the normal rotation mode, the Select knob controls the channel with corresponding readout on the LCD. Normally, pushing in the Select knob brings up the squelch threshold mode, which is set digitally by rotating the knob. If the Select knob is held in during power-on, it enables manual triggering of the autotuner. After that, pushing in the Select knob starts the autotuner in a handsfree 10 second tuning cycle mode. Settings of the autotuner are memorized on a per-channel basis, so the antenna is always instantly tuned when selecting each channel if the same antenna is used. If no autotuner setting has been memorized, it reverts to 50 ohms.All of the switches, the knobs, and the LCD are recessed in a mechanically protective manner, down into the plastic with extremely stout design, and there are rubber O-rings and gaskets which give the controls a solid look and feel when operated. The design is entirely different from the fragile front panel of most amateur rigs. The microphone connector on the side of the chassis, is of the low profile molded surface-contact type secured by small bolts, similar to those found on Vertex FM business transceivers. CHANNEL PROGRAMMING The VX-1200 can store up to 500 channels of duplex or simplex HF frequencies with selective calling and antenna tuning for each channel. Frequency, mode, and feature programming can only be loaded and controlled by an external computer using the SVC-1200 Programmer system with supplied proprietary software. Up/downloading is accomplished by removing the microphone and connecting the SVC box with a special cable to the computer via serial port. Each "channel" is displayed with a label of 8 alphanumeric characters in the LCD. All channel labeling is custom programmed by software prompts according to the users needs. It may be convenient to label the channels with the frequency and mode, or simply call them Channel A or 1234. Capacity of 500 channels may seem like a lot, but it is certainly not enough to program every HF frequency into memory! So the programmer will need to determine what frequencies and modes are appropriate or assigned and enter them into software in some logical order. After programming, the microphone is reconnected and the Select knob can be rotated to select the desired channel. It takes several minutes to rotate through all 500 channels looking for the desired one! NO VFO At the present time, there is no continuous VFO frequency tuning method at all, and the most likely field programming would be by use of a portable or laptop computer capable of running the DOS loading program. So with this type of channelized frequency method, the VX-1200 is probably not well suited to casual amateur use or unknown frequency situations. However, it is certainly appropriate and perfect for applications where frequency planning is done prior to use, including: commercial, marine, land mobile, scientific, specialized communications, expeditions, nets, scheduled operations, organized applications, or emergency systems. It is rumored that a new version of the DOS programming software which would allow VFO operation may be in the works. BATTERY CHARGING The VX-1200 includes an FNB66-LI lithium-ion battery pack (14.4V). This battery slides into the unit through a gasketed rear panel port, and clamps securely in place. The lithium-ion pack is charged using the CD-17 charger unit, a rather bulky plastic box, which plugs into a 4-pin plug on the rear panel of the VX-1200. The CD-17 requires a 24VDC source, conveniently supplied by the companion PA-6C switching power supply adapter for 100 to 240VAC 50/60Hz. Another 24VDC source such as a 24V solar panel, 12V to 24V DC-DC converter, or 24V vehicular system connection may be substituted in place of the PA-6C. The battery pack seems to last quite a while under normal SSB net operation, but extensive testing still needs to be done to determine the average cycle of battery lifetimes. This will vary according to operating practices. A blinking LED informs the user when battery is getting low, followed by a beep sound before transmit lockout ensues at about 9.5V. The receiver will still operate for some time longer on a low battery down to about 8.5V. Running the unit directly from 13.8VDC is possible with a simple modification. CW/DATA MODES Standard CW break-in keying, when programmed on a per-channel basis, is provided through a rear panel DB-9 connector which must be installed as an option called the DSV-1200 D-SUB 9 pin Connector Unit. For walking backpack operation, the rear connector doesn't lend itself to easy access, but when stationary portable it is quite usable. Use of a right-angle DB-9 computer-style plug puts less strain on the connector for backpack CW operation. Like most manpack units, there is no internal electronic keyer, and CW operation is looked at as a backup or secondary function option. The same rear DB-9 connector provides line-level audio connections for external DATA audio and PTT control. This functions quite well with a laptop, and was simple to hook up using PSK31 with a small laptop, connecting directly to the sound input/output mini-jacks. WHIP ANTENNA The YHA-61 antenna is simply an extremely rugged stainless steel whip with black flexible conformal coating. A custom-machined knurled PL-259 base mates with the VX-1200's teflon SO-239 front panel mount to form a sturdy low-leverage antenna system for backpack or shoulder bag use. The base of the antenna has a small spring, with a black rubber boot covering both the spring and the oversize PL-259 after attachment to the radio. The antenna can be bent vigorously around without deforming it, and little care is needed while walking through overhanging tree branches, since the antenna springs back into place. SIZE At 7.5" wide by 3" high by 10.75" deep, the entire VX-1200 unit is about the size of a mobile CB radio, and slightly larger than some of the newest miniature all band amateur mobile transceivers. But keep in mind that VX includes the battery and antenna tuner inside it! We found a small cordura travel shoulder bag to provide convenient carrying for this unit and all its accessories. It is easily slipped inside a standard backpack with plenty of room to spare for camping gear or other necessities. With all needed controls accessible yet protected on the top, the unit may be easily operated and used in motion with little concern about bumping the knobs and fumbling around. CONCLUSION The VX-1200 is a very lightweight powerful HF backpack unit optimized for ionospheric propagation communications and channelized operation on SSB. It is mechanically and electronically suited for rugged field operation. It has been a pleasure to use and test out the VX-1200. It is hoped that this article provides some practical answers to questions potential users might have, and paves the way for the VX-1200 and other VX-12xx models to see expeditionary use in the future. --------- (c) Copyright Bonnie Crystal 2001 for reprint permission: Posted originally to HFpack, The e-group for HF Backpack. <http://groups.yahoo.com/group/hfpack>
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