8-Pole Quasi-Equiripple (QER) Crystal IF Filter

Name: 8-Pole Quasi-Equiripple (QER) Crystal IF Filter
SKU: 29031
Price: 4.95 USD
Availability: InStock

This 8-pole quasi-equiripple filter is used in the IF stages of an SSB receiver or transmitter to eliminate the opposite sideband.

Designed by Mostly DIY RF in United States of America

8-Pole Quasi-Equiripple (QER) Crystal IF Filter 1

8-Pole Quasi-Equiripple (QER) Crystal IF Filter 2

8-Pole Quasi-Equiripple (QER) Crystal IF Filter 3

8-Pole Quasi-Equiripple (QER) Crystal IF Filter 4

8-Pole Quasi-Equiripple (QER) Crystal IF Filter 5

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For detailed documentation, go to: https://github.com/mostlydiyrf

This 8-pole quasi-equiripple filter is used in the IF stages of an SSB receiver or transmitter to eliminate the opposite sideband.

Some would say a crystal-based IF filter is the very heart and soul of a good SSB rig. There’s no doubt that a clean, ripple-free and narrow-skirted “xtal” filter is essential for excellent performance, especially in a receiver. They are, however, among the most difficult builds for a home-brewing amateur to pull off. Among the easiest types, though, are quasi-equiripple designs that do require using xtals closely-matched in resonant frequency (within 50Hz, but the closer the better), but that do not require the careful measurement of “motional parameters” or ESR. More on QER crystal filters can be found in recent (since at least 2011) editions of the ARRL Handbook.

Kits and fully-assembled & tested filters are available for 4.9152, 9.00, 11.059, or 12.00MHz. Specify frequency when ordering. Fully assembled and tested filters are produced on demand. Shipment is within 14 days.