The Ferrite Snap On Combo Pack is a convenient solution for troubleshooting RFI/EMI with various diameter cables ranging from 1/4″ to 3/4″ for use as either single turn or multiple turn ferrite chokes. The snap on chokes are useful for RF coax, AC/DC power cables, and device interconnection cables.
Always use a snap on with a larger inside diameter than the diameter of the cable and use multiple turns if possible (2 turns through the snap on is the same as 4 snap ons with 1 turns). Included in these combo packs are our most popular snap on sizes as follows:
Feed Line Chokes for Vertical Antenna with radials/counterpoise
Feed line chokes for verticals require a special arrangement to isolate the coax feed line from the radials and ground system. Schematically, a good feed line choke for verticals with radials should be built as follows:
Our CUV-1-1500 and CUV-1-5000 feed line chokes are all internally connected to isolate the coax feed line as shown above.
Th CUV-1-1500 unun is a common mode feed line choke for vertical antennas with radials that need to be isolated from the coaxial feed line to keep common mode current from using the coaxial braid as another radial. Very effective with high choking of 1K-5K from 1.8-61 MHz and also incorporates two side studs/wingnut terminals for radial or ground connection at the antenna while isolating the coax feed line braid from the radials via the internal common mode feed line choke. Top terminal with stud/wingnut for vertical connection enclosed in a 4″ x 4″ x 2″ box..
To reduce receiver common mode noise for long runs of coax to your antenna, use a MC-1-1500 or CU-1-1500 feed line choke at the station end of the coax.
