Using existing RF circuit in general homes. Sharing of STB, DVD with a few rooms. Flexibility in setting TV format such as PAL/NTSC and Sound IF to accommodate users from all part of the world. With the wide frequency range of 471.25MHz-885.25MHz, selectable transmitting frequency and correspondence frequency display and in built memory minimize and avoid interference. The use of broadcast standard PCB circuit designed enhanced stability and better picture quality further. To modulate Audio/Video/signal to RF signal over coaxial. With this product, user in the room can share and remote control their Digital Set Top Box, DVR, DVD. AV Receiver which are placed in the living room. This is made possible by converting the A/V Signal from the A/V equipment to RF signal and send to various rooms over RF circuits. External setting for NTSC/PAL B/G,I,D/K,L.M TV formats for global use. Compatible with set top boxes and other A/V sources. UHF modulator - PAL/NTSC selectable. Output channel selectable. USB power supply. RF Frequency Range:471.25MHz-885.25MHz Channel Range: PAL:21-69; NTSC:14-83 Default Factory Setting: Channel 21 (471.25MHz).PAL RF Output Impedance:75 unbalanced Video Input Impedance:75 TV Format: PAL/NTSC Sound Carrier Frequency:4.5/5.5/6.0/6.5MHz Power:USB 5VDC Power Consumption:less than equal 1W Item Size:104x68x24mm/4.09x2.68x0.94in Item Weight:80g/2.85oz Note:Different factory batches do not affect the use of the product. Colour:Black Material:Metal Package Contents: 1 * Modulator 1 * Data Cable Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.