From: Charlie Mazoch <"CharlieM"@Flex.Net.Inc> Subject: FT-847 Mod to install xtalfilter: An International Radio xtal filter 2.1Khz wide, 455Khz filter will fit into this radio. The top of it can be stuck to the diecast housing on left front of radio looking at the bottom of radio with front facing forward. I used double sided tape to mount it to the chassis between the circuit board and chassis. The pins of filter are facing back and to the top. A couple of short runs of minature coax and connectors and the ceramic filter on receive can be replaced. There was a lot of difference using the xtal filter in place of the original ceramic against strong signals close to the receive frequency. Model # of filter is #702. Charlie Mazoch Jr. WA5KVS 2139 Vinita Street Houston, Texas 77034 charliem@flex.net YAESU FT-847 ALL MODE HF/VHF/UHF TRANSCEIVER WARNING! Any modifications made to your equipment are performed at your own risk. Be aware that these mods will probably void your warranty. A modification to open up the radio. Remove bottom cover..near battery there are 6 solder pads numbered 1 thru 6....pad 1 is already shorted with a chip resistor.....short pads 2 and 3 with solder...check pad 6 and if it has a chip resistor on it ...remove it...this one has to be removed to go out of band on hf and 6m.....replace cover and turn on radio while holding in the lock and fast buttons....this resets micro-processor and you will also lose all your memories that you have entered...you will have to reprogram these....TX coverage will be 1.8-76mhz with no gaps...DO NOT TX BETWEEN 30-36MHZ -- not only is it illegal, but you may damage the HF PA. Thanks to Tom KF4TRZ, Brent K9WV, and others for sharing this information. ------------------------------------------------------------ Sirs, Attached is a text file containing instructions on how to enable the Yeasu model FT-847 to transmit out of band. I believe this will be of interest to your readers. Please post this file on your site under "RADIO MODS." The following text shows the exact contents of the attached file. Thank you, Jeff Parker KF4SCI Yeasu FT-847 Out Of Band Modifications WARNING! There are apparently different versions of the FT-847, as such some may not modify. Modifications made could void your warranty. Perform any modification at your own risk. The author assumes no responsibility whatsoever from the use or misuse of this information. Please verify and obey local regulations prior to transmitting outside your license allocations. (c) 5 JAN 00 KF4SCI Once modified the Frequency coverage of the FT-847 in TX mode is: 1.8 MHz to 76 MHz (no gaps) CAUTION: DO NOT TRANSMIT IN THE RANGE 32 MHz TO 37 MHz AS YOU ARE TRANSMITTING INTO A LOW PASS FILTER AND COULD DO DAMAGE TO THE POWER AMPLIFIER. 137 MHz to 174 MHz and 410 MHz to 470 MHz The modifications are as follows ... Remove bottom cover you should see the backup battery, on the left side their are 6 solder pads numbered 1,2,3,4,5,6. Pad number one should already have a 0 ohm chip resistor across it, short pads 2 and 3 with 0 ohm chip resistors, small wire, or a simple solder bridge. Verify that pad 6 has no chip resistor on it. If indeed it does, remove it. The radio will not transmit out of band on HF or 6 meters if this resistor/jumper is left intact. Replace the cover, make all necessary connections such as power, antenna etc. Now press the fast and lock buttons simultaneously while powering up the radio. This will reset the microprocessor resulting in the loss of any memory presets. Your modification is complete. RF power output should be the normal 100 watts through the six meter band however, output power may diminish to as low as 20 watts as you reach 70 MHz and beyond. This is normal as no cause for panic. 137 MHz to 174 MHz and 410 to 470 MHz ranges should produce a respectable output power of 50 watts.