Fox Delta LCD SWR kit
Fox Delta is a group of people, formed a few years ago by Dinesh VU2FD. It deals with the development of kits for amateur radio needs. All documentation is available on the website so everyone can be inspired or build a kit from their own parts. The prices are really popular, interesting selection and who is not quite good at assembling kits can order a finished product for an additional fee.
One of the offered kits is also Dual Channel LCD SWR Meter with PIC16F877A. The authors of the project are Antonio I2TZK, Frank K7SFN a Dinesh VU2FD. Allows power measurement, reflected power and PSV within the range specified by the sensor (KV/144MHz, 1-100W, 10-2000W). The measured data is displayed on a two-line LCD display or on a computer connected via a serial port (SWM3 version via USB).
I ordered and paid for the kit online, and in about a week I had the package at home. The price was approx. 83EUR: SWM2 + senzor Dual scale bridge + postage. And it could consist…
The first impression of the kit is very spoiled by the mechanical design of the boxes. The sensor box has gaps on the edges of the cover, as well as the connectors and the main box has fairly large LED holes, buttons and connectors. Even white color is more suitable for kitchen appliances than for amateur radio equipment. I solved this with black spray and rubber bushings and the result looks better. The sensor can be placed out of sight or make your own box.
PCB mounting is relatively simple, the areas are large enough to be soldered easily. The most difficult way is to wind the toroid. However, the number of threads is missing from the documentation! Examining the photos of the sensors, I estimated the number of turns on 25, which is a fairly real number. A piece of thin Teflon coaxial passes through the toroid. Although the manufacturer declares a range of up to 2kW, but I'm not sure, whether it is real.
Assembling the main circuit board is also easy. Just follow a proven mounting procedure - from the smallest parts to the largest, last to install transistors and ICs. Two smaller ones are connected to the main printed circuit board via flat connecting cables with connectors - display and control + LED.
On devices assembled with their own hands, the most interesting moment is the first switch-on. SWM2 came out, the display lights up when the power supply is connected. The trimmer on the main circuit board was enough to deliver the contrast and SWM2 was ready for calibration. This is described in the documentation and is similar to the standard PSV meter.
Screen remote station including power measurement and PSV software I2TZK
This function can also be used for a remote station, where the serial port is "extended" via LAN or Internet.
The calibration is described in a document available on the FoxDelt website. There seem to be quite a few steps, but setup is quick and only takes a few minutes. I did not verify the accuracy of the measurement, but it is probably given mainly by the sensor (frequency dependence). When comparing with the wattmeter built into the transceiver, I did not find a deviation in any band.
LCD SWR Meter FoxDelta is a useful addition to the ham shack of a radio amateur and if one eye is closed on the version, offers for small money the functions of several times more expensive meters. HAM, which is not very technically proficient, can also assemble from the kit.
Info:
http://www.foxdelta.com/products/
www.i2tzk.com
