In 1987 i built a small tracker use BF224 RF transistor as a sqegging oscillator,
1t was just over an inch long and slightly bigger in diameter than an SR44 button cell. It had range of approx.,80 meters line of sight on level ground with the osc.,4 inchs above ground level,and relying only radiation from the osc., coil.This little device worked well for 13 years with battery change every 6/8 weeks until the cat died.
In order to get suffecient amplitude from the sqegging pulse i had to make simple AM rec., with a bandwidth of about 2 mhz.Now that i need to use the device again i find that because of the bandwidth of the rec.,the range has become only 20 meters, due to what i think are spread spectrum transmmisions.
A transmitter is needed useing more up to date components,and possably a minature xtal for freq.,stability.Can anyone help?
dmsmith.
1t was just over an inch long and slightly bigger in diameter than an SR44 button cell. It had range of approx.,80 meters line of sight on level ground with the osc.,4 inchs above ground level,and relying only radiation from the osc., coil.This little device worked well for 13 years with battery change every 6/8 weeks until the cat died.
In order to get suffecient amplitude from the sqegging pulse i had to make simple AM rec., with a bandwidth of about 2 mhz.Now that i need to use the device again i find that because of the bandwidth of the rec.,the range has become only 20 meters, due to what i think are spread spectrum transmmisions.
A transmitter is needed useing more up to date components,and possably a minature xtal for freq.,stability.Can anyone help?
dmsmith.
