Figure 7 Figure 8
14. To reinstall the PCB, you need to route the battery lead through the cutout in the chassis (see green arrows in
Fig. 7) and carefully align the three (3) pins sticking out of the chassis into the mating connector on the PCB
(see yellow arrows). This can be a little tricky. Look at Fig. 8 also. The arrows show the pins and jack mating.
15. Replace the five (5) screws that hold the PCB in place and reconnect the two (2) ribbon cables and two (2) coax
connectors. Replace the two (2) side screws and the bottom screw.
16. Reconnect the speaker cable as you reseat the top cover. Replace all top cover screws.
OPERATION
The new SSB filter replaces the function of the MuRata filter while the CW filter functions in the role of the
Optional Filter. Operation of the One-Board Filter is straightforward.
1. Set Menu #38 to CW. (If you do a system reset, the default is OFF.)
2. When you are in the CW, CWR, or DIG modes, you can turn the CW filter ON or OFF by pressing the
NAR key (Function Row 7, Key C).
On receive using the new SSB filter, you will experience the greatest benefit of you use a good-quality
comminations speaker or headphones. You will hear a modest improvement even using the FT-817's internal
speaker.
You can also improve your overall talk-power by adjusting the transmit-carrier insertion to place your voice-power spectrum
optimally in the SSB filter's passband. One approach to perform this adjustment is as follows:
1. Use a remote receiver of good quality to receive the transmitted signal from your FT-817.
2. Attach a true rms voltmeter to measure the audio output of the remote receiver. The averaging time constant should be
a few seconds.
3. Read any text you desire in a monotone voice with your normal pitch for 30-60 seconds and have the voltmeter value
recorded.
4. Now adjust the transmit-carrier point (T LSB CAR ÆMenu #56; T USB CAR ÆMenu #57) and repeat step 3.
Adjustment of this parameter shifts your voice in the SSB filter passband.
5. After you have collected adequate data, select and store the optimum value for both USB and LSB.
You may be able to improve your receive performance by adjusting the receive-carrier point (R LSB CAR ÆMenu #54; R USB
CAR ÆMenu #55). This can be done by "ear" or by using the true rms voltmeter to monitor the FT-817 audio output and
adjusting the receive-carrier point while monitoring the monotone read text.
NOTE: If you are interested in understanding more about the performance of these filters, then see the QRP Quarterly article by
K9QI (http://www.w4rt.com/obf/QQ-Oct-01-Filter-Review.pdf). Although the radio in the article is the Yaesu FT-817, both the
FT-817 and the FT-817ND use the MuRata CFJ455K ceramic filter as the stock filter. The performance of the filters in both
radios is essentially the same.
WARRANTY: ONE BOARD FILTER is warranted for a period of one (1) year from the date of purchase to be free of electrical defects in materials and
workmanship. If the ONE BOARD FILTER is determined to be defective, the defective item(s) will be repaired or replaced, at the sole option of W4RT Electronics,
provided that the purchaser returns said item(s), postage prepaid, with proof of purchase to W4RT Electronics, ATTN: Technical Support, 3077-K Leeman Ferry Rd,
Huntsville, AL 35801. Include a description of the problem, daytime phone number, email address, and return mailing information. Any modification to the ONE
BOARD FILTER by purchaser voids the warranty. The warranty applies only to the original purchaser and is not transferable. Any damage to the ONE BOARD
FILTER due to the installation method or technique used by purchaser is the sole responsibility of purchaser and W4RT Electronics has no liability whatsoever.
22 March 2005
Copyright ©2005 by CyberAir Development Corp. All rights reserved.
W4RT Electronics, W4RT, and ONE BOARD FILTER are trademarks of CyberAir Development Corp.
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