frequency you plan to use. In the case of the Logi, 900 MHz was used to calculate the dimensions. A gain of 10 dB can be obtained with a reflector side length of one wavelength. A two wavelength reflector can be used to achieve upwards of 12 dB gain! It just means you’ll have a bit more wind resistance to factor in.

The positioning of the Logi as the active element must also take into account the frequencies you’ll be dealing with. Thankfully, the physical

layout of the circuit board takes care of this for us automatically! The narrow front end of the board should be placed so that it points into the vertex of the reflector plates. Rotate the board so that it lines up directly with the seam created by the two plates. This allows one side of the Logi to collect (in receive mode) or emit (in transmit mode) the electromagnetic energy from one plate to one side of the active element. If the Logi is turned 90° so that it does not line up in parallel with the seam, the antenna will not function properly.

The boom length that positions the Logi at the focal point of the reflector is also critical factor. This will require a bit of trial and error to get things just right. Use a piece of PVC pipe (1/2” to 7/8” will work well) with a slot cut in the end just big enough to wedge the entire Logi in place. The narrow front edge of the circuit board should be positioned between 1.5” to 3” from the seam formed by the two reflector plates. PVC couplers can be mounted in the vertex of the reflector to allow you to slide the boom in and out while testing. Once the optimal position of the Logi is set, tighten the coupler and your ready to go!

BUILDING A REFLECTOR GRID

Building a reflector grid antenna as a home-brew project is a little harder then the corner reflector. It would be very difficult to achieve the proper parabolic shape for the reflector by banging on an old BBQ grill! The best way to insure your antenna will function the way you want is to use a pre-fabricated dish. There are a few different dishes that are easy to get and very affordable. We experimented with the ISM19R and ISM24R and found that they work wonderfully with the Logi!

Look at the how the Boss used a piece of PVC and a few couplers to form a boom. He cut a slot in one end of the PVC pipe to hold the Logi antenna in place. Then he used a nylon wire tie at the end of the boom to squeeze the slotted pipe like a vise! Wow!!! Simple to make and highly effective!

If you plan to do the same, here is a quick shopping list:

LPY2 • 7

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Ramsey Electronics LPY2 manual Building a Reflector Grid
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LPY2 specifications

Ramsey Electronics LPY2 is a versatile and highly respected model renowned for its impressive performance in low power FM transmitters. This device stands out in the field for both amateur and professional use, making it a popular choice for various broadcasting applications.

One of the key features of the LPY2 is its simplicity and ease of use. Designed for ease of assembly, it is suitable for hobbyists and individuals looking to delve into the world of radio transmission without a steep learning curve. The kit comes with clear instructions, making it accessible for users with varying levels of technical expertise.

The LPY2 operates within the FM broadcasting band, typically covering a range of 88 to 108 MHz. This capability allows users to transmit audio signals over a significant distance, depending on the antennas used. Its effective range typically spans a few hundred feet to several miles, making it ideal for small community radio stations, personal broadcasting, or event-specific applications where a localized signal is needed.

Technologically, the LPY2 integrates various features that enhance its performance. It utilizes a low-noise oscillator and a power amplifier, which improves the signal quality and range without compromising clarity. The transmitter is built using discrete components, ensuring minimal interference and high stability, critical factors for clear audio transmission.

A notable characteristic of the LPY2 is its adjustable output power. This flexibility enables users to tailor the transmission strength according to their specific requirements, whether to maintain a low profile or to ensure broader coverage. The device also features built-in modulation for varied audio input, allowing users to connect various audio sources like microphones or music players seamlessly.

Additionally, the LPY2 is noted for its robust build quality and reliability. Built to withstand continuous use, it includes protective measures against over-voltage and overheating, ensuring its longevity in various environments.

When it comes to connectivity, the LPY2 includes standard RCA audio inputs, making it compatible with a wide range of audio devices. This compatibility is essential for users who want to diversify their content sources and enhance the broadcasting experience.

In conclusion, the Ramsey Electronics LPY2 is a formidable choice for anyone interested in low power FM broadcasting. With its user-friendly design, flexibility in output power, and high-quality audio transmission capabilities, it serves as an excellent tool for both novices and experienced broadcasters looking to make their mark in the radio spectrum. Whether it’s for personal projects or more extensive broadcasting initiatives, the LPY2 delivers reliable performance and excellent features tailored to its users' needs.
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