The TFR-40 from KD7S
As pointed out by Mike Herr, WA6ARA, conventionally designed QRP transceivers can be awkward to use when operated from a ground level position because the controls are almost always placed on the front of the cabinet. Mike suggested a better way might be to put the controls on the top of the case. However, I believe that this approach simply trades one set of problems for another. With the controls on top, it may be difficult to operate the rig from a picnic table or a pickup truck tailgate.

I believe a truly "Trail Friendly Radio" should be equally easy to operate while sitting on a log, placed on the ground, perched on a picnic table or even at home on a conventional operating desk. My entry into the ARS challenge -- The TFR-40 -- meets all these requirements.

For the controls to be in constant view the transceiver must be positioned so the panel is always pointing toward the operator's face. One simple way to do this is to place a pair of small, moveable brackets on either side of the rig's enclosure. These brackets elevate the radio sufficiently to allow it to swivel through a 90-degree arc. The accompanying graphic illustrates the concept.

The main tuning control, RF gain pot and headphone jack are mounted on the front panel. On the rear panel is the antenna connector, key jack and power connector. All controls and connectors are sufficiently recessed to protect them from damage during transport and operation.

Packaging aside, there are additional attributes which render a transceiver genuinely "Trail Friendly." An impromptu survey among members of the QRP-L Internet Club suggested such a rig should be small, lightweight, power thrifty, rugged and with a minimum number of controls. Again, the TFR-40 meets these goals.

The transceiver itself is a built-from-scratch NE 40-40 as described in the September 1994 issue of "QST." As mentioned previously, there are only two operating controls on the front panel as shown in an accompanying graphic. Power consumption is around 20 milliamperes on receive and just over 300 milliamperes on transmit for one watt output. The PC board measures 2.8 inches by 4 inches so the finished package is small and lightweight. Both the homebrew enclosure and support brackets are made from 3/16 inch ABS plastic which results in a very strong case.

Being a spartan rig doesn't necessarily mean it is totally devoid of convenience features. For example, it has built-in battery reverse polarity protection. The transceiver can be operated from a variety of power supply options including a voltage regulated solar panel. There is a large recessed calibrated dial on the front panel. A 6:1 reduction drive makes tuning easy and precise. The backplane of the dial is made from a piece of glow-in-the-dark plastic. A two or three second blast from a flashlight will yield 15-20 minutes of dial illumination in a darkened tent or inside a sleeping bag. There is a built-in storage compartment for the support brackets when the rig is not in use as well as snap-on covers for the front and rear panels.

While the TFR-40 has yet to see action in the mountains, I did use it at home to compete in the October Spartan Sprint. Instead of sitting on the operating desk, I placed the rig on a small plastic table at about knee height. The enclosure was angled up so I could see and adjust the controls easily. At the same time, the battery connections, key line and antenna lead were securely connected to the back of the cabinet and well out of the way. This arrangement closely simulated operation from a campsite, but without the bone-chilling cold and hungry mosquitoes

There is no doubt that The TFR-40 will see a lot of outdoor action in the months to come. Besides being a proven performer in the shack, the rig is designed to be equally at home in the back yard, at the beach or beside the still waters of a pristine Alpine lake. It is indeed a "Trail Friendly Radio" by every definition.