BASIC Desktop Computer RFI Kit - AC Powered
This RFI kit is specifically selected to suppress most household computer device RFI problems. It contains a large ferrite ring for AC power supply protection and Snap On ferrite split bead filters selected to eliminate RFI from 1 to 300 MHz. The beads are easy to use, don’t require modification of the protected equipment and work in almost all cases, even when plug-in filters fail.
The RFI-Desktop kit is meant to be used with a AC powered computer (desktop type) with up to 6 input/output signal lines and an AC power cord line coming into the device. Included are one large ferrite ring filter and six, 3/8” inner diameter snap on split ferrite bead filters for the input/output lines.
Installation is easy. AC power cord through ring filter multiple times and snap on filters on I/O cables nearest computer - problem cured!
For additional devices like a printer and AC powered speakers, consider the Deluxe Desktop RFI Kit with additional filters.
50 ohm coax to 75 ohm balanced output baluns are useful for low (< 1 wavelength) dipoles exhibiting 75 ohm characteristic impedance or for matching to balanced ladder line whose endpoint impedance is near 75 ohms.
50 ohm coax to 75 ohm CATV coax connections are easily done with a 1.5:1 unun with SO-239 connectors on input and output. Likewise 50 ohm coax to unbalanced verticals or loads near 75 ohms can be matched with a 1.5:1 unun.