Followit has experience in making VHF transmitters since 1973. The technique is well tested very reliable and constantly refined. For instance, our transmitters are frequency stable in a wide temperature range.
The use of radio transmitters on animals is wide and the objectives are very different. For many years, the same technique is used for security, surveying etc.
Our transmitters are adapted to the project, not the other way around.
We produce transmitters operating on frequencies between 138 and 175 MHz and on 433 MHz (special applications). All electronic parts are embedded in an inert, protective and waterproof plastic casing.
Generally, the batteries, the antenna and an attachment device are included, giving the customer a complete radio package, ready to use. Moreover, it is possible to design some of these packages so that the batteries can be replaced. (Replacement of batteries cannot be done for non pre-prepared transmitters.) The transmitters are activated by an external On/Off magnet read switch.
Before the transmitters are delivered, we perform rigorous tests to check that they work properly. The TXV-10 transmitter is very frequency stable (+/- 250Hz) over the temperature range and adjusted for maximal performance (range and life) according to the parameters given.
For all transmitters, the standard pulse length (width) is set to 18 ms, and the pulse period, i.e. the time from the initiation of one pulse until the next one starts, to 1500 ms, giving a pulse rate per minute (ppm) of 40.
Contact Pro is a radio tracker that offers excellent directional accuracy and 200 channels to avoid the risk of using the same wavelength as another user, together with the ability to track several transmitters at the same time.
Including a scan function of 40 customer programmable channels. The receiver includes the latest of technology. It is based on many years of experience from development, production and field use of older generation receivers. It is robust but small, easy to use and covers a wide range of frequencies. The receiver covers any 2 MHz* band between 138 to 232 MHz** and is supplied with an internal foldable antenna (RX-98H)***. The receiver includes a scan function of 40 programmable channels. Channels can independently be included or excluded in the scan. The time before moving on to the next channel can be set from 1 to 9 seconds. The frequency can be set to the kHz (.00X MHz) by turning a dial. Dials control fine trimming of the frequency (tone) within the last kHz and the gain. The frequency set is shown on a LCD. The strength of the signal received is indicated on a LED array and also by a loudspeaker or earphone. The receiver is powered by 2 alkaline 1.5 V. batteries which last for about 10-12 hours. Alternatively, the receiver can be used with re-chargeable batteries (NiCd or NiMH).
* An adjacent 2 MHz band can be included
** 138-155 MHz for the H model
*** The model RX-98E has no antenna included
This is the most popular antenna of them all. It is a four-element Yagi-antenna for hand-held tracking. The antenna has foldable, flexible elements and is easy to handle when tracking in the field. It also has very good directional properties. Weight: 800 g, size: 1120x1120 (40) mm, gain: 8 dB.