Pilot Products

February 1, 1995

Aerocom Jr intercom

At the low end of the portable-intercom spectrum, it is reasonable to expect less. Fewer features, weaker amplifiers, and low-grade fit and finish often denote an intercom whose maker has had to cut corners to cut costs.

So it's refreshing to find that PS Engineering's latest portable, the Aerocom Jr., manages to offer low cost without appearing to be a blue- light-special refugee. The extruded aluminum case is the same one used with the more expensive Aerocom II and Aerocom ST, and the cords feel sturdy enough to handle the inevitable rental-airplane, seat-track crunch.

How, then, does the Aerocom Jr. come about its low-ball $169.95 price? Employing off-the-shelf parts helps. PS Engineering starts off using the existing circuit board from its bargain-hunter PM 501 intercom. Also, while the other Aerocoms use costly internal ni-cad battery packs, the Jr. sports a front-panel tray for a garden variety nine-volt cell.

Despite the modest entry fee, the Aerocom Jr. contains some useful and unexpected features. A pilot-isolation circuit cuts the left-seater out of the loop of intercom chatter. The controlling switch, marked "All," "Iso," and "Off," also manages intercom power; there's no lighted indication that the unit is on. PS Engineering says that using a lamp to indicate power-on would consume more energy than the idle intercom itself. Also included is a monaural music input that is modulated by PS Engineering's Soft Mute circuitry. However, the music tails off only during intercom activity, so incoming radio signals do not activate the muting function. Pushing the Volume button turns Soft Mute off and on.

One feature common to most of PS Engineering's intercoms but lacking in the PM 501 and Aerocom Jr. is separation of microphone circuits. Although each headphone is powered by a separate amplifier (preventing changes in volume and power output with the number of headsets on line), the microphone-voice-activated switches (VOX) are combined. This means that when one person speaks, all the mics are open.

All told, the Aerocom Jr. performs admirably. Sufficient audio power exists to overcome the din of moderately loud cockpits, and the voice-sensing circuitry works smoothly and unobtrusively. We did notice that a bit more noise is introduced into the audio line with two microphones connected than is true with the Aerocom II, but it's really only obvious when you're looking for the differences. For most airplanes, the Aerocom Jr. will function quite well; those in open-cockpit airplanes or unusually loud quarters should consider an intercom with individual VOX circuits.

PS Engineering claims a minimum of 10 hours' activity on a single alkaline nine-volt cell, a number we believe is accurate. Replacement of the battery has been made simple and quick, thanks to the front-panel bay. An external-power cord comes with the intercom.

By itself, the Aerocom Jr. is a two-place intercom, but a $49.95 expansion box may be attached that accommodates two more users. As with Aerocoms of old, the Jr. places all controls on the forward face of the intercom, and all wire connections at the back. Such an arrangement generally proves successful, although some installations work better with everything on the top of the intercom. Fortunately, the Jr. can really be called a set-and-forget box, so there's no terrible penalty in this setup. Separate connections for push-to-talk switches adorn the rear of the unit, too, although the Aerocom Jr. by default directs only the pilot's microphone to the aircraft radio when a PTT switch is activated anywhere in the circuit.

For more information, contact PS Engineering, 9800 Martel Road, Lenoir City, Tennessee 37772; telephone 615/988-9800.

Soros Ventube

Every winter, single-engine Cessna fliers get used to the "roasted feet- freezing face" syndrome caused in part by the drafty air vents in the upper windshield. Because of the air leaks, heat rarely rises above waist height. All that air rushing in through the "closed" vents makes a lot of noise, too.

Soros Inc. has solved the air vent problems with their recently certified Ventube replacement air vent. The Ventube is a two-piece assembly consisting of the push-pull vent sliding within an outer sleeve. A slot cut in the inner vent tube "grabs" the dowel when turned clockwise and tightens the tube into place like a quarter-turn fastener on a cowling. A rubber O-ring is used to seal off the drafts and cut down on wind noise.

The original Cessna air vents, often called orange juice cans because of their resemblance to the frozen concentrate container, have been known to pop open or blow out under pressure.

After installing the Ventubes in a 1975 Cessna 172M, we found them to work as claimed, but the lower noise level unfortunately called our attention to leaky door seals.

With an outside air temperature of 25 degrees Fahrenheit, the Cessna stayed warm enough not to require the use of gloves which, at this temperature, were required equipment in this particular airplane.

The replacement Ventubes greatly resemble the original Cessna versions and will fit most Cessna singles from the 120 to the 210F. Installation was a piece of cake, according to our mechanic, who was impressed enough to request a pile of Ventube brochures for his customers. It is necessary to drill a hole in the right Ventube to allow the outside air temperature gauge to be reinstalled.

According to Ventube developer Donald L. Horton, Cessna has considered utilizing the Ventube for their renewed single-engine airplane production.

Two different Ventube sets are available. The standard tube fits most Cessnas and costs $69.95 for a pair. A longer tube, with openings set 180 degrees from each other, directs incoming air forward toward the windshield as well as aft towards the cabin. A pair of the long tubes costs $119.95.

Although not as nice as the Wemac nozzles that were custom designed (read expensive) for AOPA's Better Than New 172, the Ventube is a cheap and effective way to beat the drafty and noisy Cessna air vents. For information, pricing, and brochures, call 800/957-9007. To order, fax Soros Inc. at 214/991-7343 or write to Post Office Box 112639, Carrollton, Texas 75011-2639. — Peter A. Bedell

The official handbook of Aviation forms

The plot isn't much, but the utility couldn't be higher. Need a VOR check log? A form for determining aircraft costs? Have a checkride coming up and forgot the FAA certificate application? It's all in there. All one need do is plop the book down on a copying machine or tear the form out. An envelope tossed inside the back cover contains a NASA incident reporting form, an aircraft bill of sale, and an aircraft registration form. There's even an application for VA flight training benefits.

Besides forms, the book lists sources of information. There are telephone numbers for all FAA computer bulletin boards, lists of aviation publications, lists of aviation organizations, telephone numbers for FAA Flight Standards Regional Offices, and even a map showing fuel taxes by state. Available for $39.95, plus shipping, from Specialized Publications Company, 405 Main Street, Parkville, Missouri 64152; call 816/741-5151. — Alton K. Marsh

Avocet Vertech pilot Altimeter watch

Pilots are suckers for gadgets. And one of the more popular recently is the pilot-specific watch. We have seen timepieces with altimeters and magnetic sensors installed, big honking watches that could double for aerobic wrist weights.

Avocet, a well-known name in bicycling, has a slightly different tack. Its Vertech Pilot watch ($129.95) is slimmer and more compact than some other pilot-pleasers we've seen. It's also considerably more stylish than some of the other feature-laden watches on the market.

Looking like a refugee from the bicycling world, the Vertech Pilot contains the usual timekeeping functions as well as a surprisingly accurate solid-state altimeter. Once calibrated, the altimeter proved remarkably sharp, even up to 22,000 feet in an unpressurized airplane. More often than not, it agreed within 20 feet of the aircraft altimeter from sea level to the flight levels. On the primary display of the watch, the altitude takes the lead position, at the top of the bezel. Altitude is shown to 10-foot resolution. Calibration is important, since the watch cannot convert sea-level barometric pressure into usable altitude corrections; you must start from a known altitude or elevation.

On that main display there's also the time and temperature. Unfortunately, the temperature readout was wildly inaccurate, more likely showing the vital signs of the human wearing it than anything resembling ambient. The manual warns that when worn against the wrist, the watch will show abnormally high readings; in any event, overall accuracy is listed as a mediocre plus or minus 4 degrees Fahrenheit.

Other functions include a vertical-speed indicator, with traps for the greatest rate (either going up or down, but not both) and the highest altitude experienced. What's more, the Vertech will keep track of the total vertical feet climbed, which can be an impressive number if you forget to reset it between flights. There's also a function allowing you to set a climb or descent timer, which then gives the average climb or descent rate within that timed run.

Another feature of the Vertech is an adjustable barometric pressure function. However, it does not calibrate the main altimeter functions and can only offer a rate of change over time. For the pilot, this is a function of dubious value.

Ease of use marks the Vertech Pilot as a gadget watch that even the techno-averse can master. The function switches are large and well marked, and the menu logic conforms to a standard even non-programmers can fathom.

For more information, contact Avocet, Post Office Box 120, Palo Alto, California 94302; telephone 415/321-8501. — MEC

CheckMate checklists

Admit it: Checklists are a fact of life. Even hardened old graybeards admit that good checklist procedures will help prevent formation of miscues on the dreaded error chain. Unfortunately, some of the checklists provided by the airframe manufacturers either fall apart at the sight of hard work or are so obviously written by the legal department as to be useless.

Safe Flight, Inc., has a slightly different take on the subject. Its CheckMate series of checklists offer all the important points and numbers found on the factory lists, but in a more colorful and useful presentation. Each of the $12.95 checklists is model specific and in most cases model-year flexible.

The formats include pocket-sized, the typical Jeppesen-binder size, and a large, thickly laminated plate measuring 9.5 inches tall and 9 inches wide. On the smaller lists, there are the usual callouts for preflight, engine start, taxi, before takeoff, takeoff, climb, cruise, descent, before landing, after landing, shut down, and securing the aircraft.

More important, the lists provide speeds to fly in the appropriate places. And the larger format contains useful information on emergency procedures, one set of cruise-power settings and speeds, and helpful tidbits like light-gun signals and commonly used radio frequencies.

Ultimately, the CheckMate checklists are slickly done and, usually, a tremendous improvement on the factory versions. For more information, contact Safe Flight, Inc., 4131 North Stratford Road NE, Atlanta, Georgia 30342; telephone 800/359-3741 or 404/264-0071. — MEC

Briefly Noted

Ever wanted to brush up on the FARs or bits from the Airman's Information Manual but couldn't come up with a way that didn't put you right to sleep? Try Perfect Publishing's FAR/AIM Flash Cards. These spiral-bound, 6-inch x 4-inch cards contain questions on one side of the card, with the answers on the reverse. They cover a broad range of questions and question types, from fill-in-the-blank to multiple choice. One version, for VFR review, costs $17 (plus $4.50 shipping) and contains 138 cards. An IFR version sells for $14 (plus $4.50 shipping) and houses 89 cards. Contact Perfect Publishing Company, 6835 Rosemary Road, Minneapolis, Minnesota 55346. — MEC

Shadin Co. has added a new model to its comprehensive line of fuel- management computers: The Shadin DigiData fuel computer. Accommodating an air-data computer, the DigiData also includes the traditional fuel-flow and consumption-calculation functions of the Microflo units. Moreover, the DigiData will incorporate input from a loran or GPS receiver to provide real-time information about fuel-to-destination, winds aloft, specific range, and myriad other calculations. Suggested retail price of the DigiData is $2,555 with all sensors. Contact Shadin Co., 1428 North 23rd Avenue, Minneapolis, Minnesota 55447; telephone 612/557-6500. — MEC


Unless otherwise stated, products listed herein have not been evaluated by AOPA Pilot editors. AOPA assumes no responsibility for products or services listed or for claims or actions by manufacturers or vendors. However, members unable to get satisfaction regarding products listed should advise AOPA. To submit products for evaluation, contact: New Products Editor, AOPA Pilot, 421 Aviation Way, Frederick, Maryland 21701; telephone 301/695-2350.