Motorola MICOR High Band to 222 MHz Conversion
Modification Courtesy of SEITS
Original Concept by David A. Cooley N5XMT

This is Optional. The radio will operate without the filter in line, but using this filter may reduce the white noise output of the exciter.

There are 5 slug-tuned coils in this filter. It is symmetrical. 

Step 1: Remove filter from the casting.

Step 2: Remove the cover from the filter.

Step 3: Remove 1 turn from the outermost coils in the filter (coils connected to the input and output).

Step 4: Remove 1 turn from the center coil in the filter.

Step 5: Remove 2 turns from the remaining 2 coils.

Step 6: Tune the coils for minimum VSWR at the operating frequency. Tuning will change when it is assembled, so make an adjustment, then put the cover back on to check it.

Step 7: Re-assemble and re-install in the casting.


Page recreated by: Kevin K. Custer W3KKC
Copyright 1998 SEITS, N5XMT, and W3KKC.

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