#177: Kenwood Dual-Band TM-D710 repair, bad filter, design issue

This video documents the repair of a friend's Kenwood dual-band FM transceiver - a TM-D710. The rig suffered a common failure for this model - the failure of a ceramic filter in the 2nd IF stage causing the receiver to become very deaf. Kenwood made a small error in the design of this rig by applying a DC bias to the filter when in use. It is generally not recommended to apply a DC bias to ceramic filters. Many thanks to Tasos SV8YM for providing detailed information on his blog about the failure mode and repair:
http://sv8ym.blogspot.com/2010/07/mysterious-case-of-withering-filters.html
http://sv8ym.blogspot.com/2010/10/lift-withering-spell-off-those-ceramic.html
The repair and design correction modification is a little tricky and tedious due to the surface mount (SMT) construction and PCB modifications necessary.

Видео #177: Kenwood Dual-Band TM-D710 repair, bad filter, design issue канала w2aew