W4RT
Electronics
™
™
A Division of
CyberAir Development Corporation
www.w4rt.com
22 March 2005
For the Yaesu FT-817 & FT-817ND
The ONE BOARD FILTER (OBF-817) is an accessory for the YAESU FT-817 and FT-817ND. W4RT Electronics
provides the OBF-817 as a high-performance, lower-cost alternative to the YAESU optional filters for the FT-817
and FT-817ND, and the OBF-817 allows the inclusion of two filters rather than the single one by YAESU. The
filters used in the OBF-817 and FT-817ND are the famous Collins Mechanical filters. The 7-pole CW filter has a
500-Hz bandwidth and the 10-pole SSB filter has a 2300-Hz bandwidth. Proper termination is included on the PCB.
For simplicity, FT-817 should be taken to also refer to the FT-817ND in the following material.
Please READ the following BEFORE INSTALLING your OBF-817.
Installation is not trivial, so you should be confident that you have the tools (SMT level), skills
and experience needed to do the job correctly. You can damage your FT-817, so be very
careful. W4RT Electronics assumes NO responsibility for any damage that may be caused by your
installation. Further, W4RT Electronics doesn't provide technical assistance during your
installation. If you need help, then have W4RT Electronics perform the installation for the
stated fee on
BEFORE you attempt the install. W4RT Electronics is not a
radio repair facility. If you damage your radio, you will have to send it to YAESU or another
repair shop.
Figure 1
1.
Remove the top cover from the FT-817 by carefully removing the seven (7) retaining screws. Retain these
screws to replace the top cover. Look in your FT-817 Operating Manual if you are unsure of which screws to
remove. As you take off the top cover, remember to disconnect the speaker plug from the MAIN-UNIT PCB.
2.
Next remove the two (2) screws on the mic jack side of the radio and the one (1) bottom screw, each denoted by
the yellow arrows in Fig. 1. Retain these screws to reassemble the radio.
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