FM Isofrequency adapter
The FM isofrequency adapter allow to synchronize one or more FM repeaters operating over the same area and using the same frequency.
Installation is very quick the unit must be connected between the STL receiver and the FM modulator and it will also generate a 10MHz reference signal used for the FM modulator: no GPS frequency reference is needed.
The unit can be controlled remotely with an optional internal webserver (opt.LAN) which will also provide a 9600bps general purpose serial port that can be used, for example, to control the connected transmitter.
The best results are obtained only through a careful planning of the iso-frequency network, we will provide a free consulting service for all customers interested.
Listen an audio sample, recorded in an urban area where the signals, coming from two transmitting sites, were received at the same level.
Starting from 0 to 10 seconds the device is bypassed, from 11 seconds onwards the delay compensation is turned on but the transmitting frequencies are still not PLL-locked.
From 19 seconds onwards, the PLL is locked and the heterodyne whistle disappears.
The FM isofrequency adapter allow to synchronize one or more FM repeaters operating over the same area and using the same frequency.
Power supply
100 – 240VAC 25VA
Dimentions
1 RU 19″ 44mm(H) x 483mm(W) x 150mm(D)
Operating temperature
0° – +50°C
Input impedance
10Kohm
Nominal input level
775mV RMS – 2.2 Vpp
Passthrough gain
0dB
Bandwidth
1Hz – 75KHz
Bandwidth flatness
+/- 0.1dB
Adjustable delay
1390uS + 4995uS / – 1245uS
MPX phase control
+/- 180°
Reference frequency output
10MHz/2500Hz (internally selectable)
