To : ALL Number : 8224 From : CLINT TURNER Refer To : None Subject : FT-470 "Keyboard Mods 1/2 Read : N/A Date : 12/13/91 11:37 pm Security : None Area : Ham Radio Forum Type : Echo For probably the dozenth time, here are the "keyboard mods" for the Yeasu FT-470 for extended receive frequency receive AND "Warp-Speed" or "Turbo" scanning. A note on extended receive coverage: There are MANY claims on how you can make a radio (an HT, for instance) "recieve from 0 to 1300 MHz". Frankly, this is a load of bull. Firstly, the filtering in the front end of the radio will limit practical reception range to a reasonable range surrounding its design range. A few radios may go down into the Aircraft region, but certainly not down into the HF range. Some radios (notably some Alinco Dual Band HT's) CAN recieve in the 800-900 MHz range by design, but many cannot. As for the FT-470, on VHF its practical range is from 130 to 175 MHz and on UHF from about 410 to 470 MHz. At or beyond these ranges, reception may be possible but the sensitivity will be extremely poor. As an example, within 2 meters, the FT-470's sensitivity is less than 0.2uV, but at the weather frequency, mine drops to about 1.3 uV. For extended frequency recieve: 1) Turn on radio (VERY important) and go into the UHF mode. 2) Hit the "VFO" to select VFO A or B and go to 450.00 MHz. 3) Hit "FM" then "RPT" and enter "0000" to make the display show 00.00 4) Turn radio OFF then ON again. 5) Hit "RPT" so that the "+" (plus) appears. 6) Hit the "REV" key. The display will show 1450.00 MHz. 7) Hit "FM" and hold the DOWN arrow and go down to, say, 512 MHz and stop. If you happen to hit the UP arrow, you will end up back on 430.000 Mhz and will have to go back to step 2 again. The frequency you move down to in this step will be the highest frequency to which you will be able to tune. 8) When you get DOWN to the frequency, push and hold the "FM" key until memory number flashes, select the "U" memory with the knob or an arrow button and then press the "FM" key to store it. 9) Press the "VFO" again to get into the A or B VFO. If it reads higher than 499.995 MHz, press the UP arrow and it will reset to 430.0 MHz. 10) Key in 450.00 MHz again and press the "RPT" key until the "-" (minus) sign appears. Hit the "REV" key until the display shows "050.00" (50 MHz). 11) Hit the "FM" key and hold the UP arrow until you get to, say, 400 MHz. Similarlyto step 7, if you hit the DOWN arrow, you will find yourself on 449.9something MHz and you'll have to step 9 again. 12) When you get UP to the frequency, do step 8 and select the "L" memory and save it. Now you are ready to tune between the frequencies in the "L" and "U" memories. To do this, hit the "MR" key until a memory number appears WITHOUT the "MR" symbol, select the "L" memory, and hit the "MR" key so that the "MT" appears. Now you can key in a frequency ABOVE the one in the "L" memory and below the "U" memory. If your "U" memory is, say, 512 MHz, you will have to either enter 499.99 MHz and move UP with the arrow key or the tuning knob, OR you can select the "U" memory. This is because you can't key in the hundreds-MHz digit. This also works on 2 meters. A good value for "U" is 199 MHz and for "L" is 100 MHz (100 MHz because it's easy to get to, not because it will receive anything). Follow the same steps, using 145.00 MHz instead of 450 MHz. When you get to step 10, there is a change, however. When you hit the "REV" key, you will end up at 745 MHz which is NOT BELOW 2 meters. At this point, hit "FM" and the DOWN arrow and go down to about 650 MHz. NOW hit the "REV" key and the display will read about "050.00". Note that this will NOT damage the radio or erase any memories, except the "U" and "L" memories, which are used here. Now, here is the high-speed scanning key sequence: 1) Go into the "ALT" mode by hitting the "FM" then "BAND" key if you are not already there. 2) Turn off the sub-display if it is on by hitting the "SUB" key. 3) Start scanning by pushing the UP or DOWN arrow key until it starts. 4) Stop the scan on a 2 METER frequency either by opening the squelch (or if if it stops on a 2 meter signal, that is OK). If it stops on a 440 frequency, resume the scan either by closing the squelch and letting it resume, or removing the antenna if it stopped on a 440 MHz signal. DO NOT stop the scan by hitting any buttons or turning the tuning knob. It must STILL be in the scan mode, but stopped by the squelch opening. 5) On a 2 meter frequency, open the squelch (it is still in the scan mode) and hit the "VFO" key. 6) Turn the radio OFF then ON and close the squelch. 7) Now, when you scan, it will scan MUCH faster than normal. Notes about this accellerated scanning: - You can get out of it by hitting either the "BAND" key or the "VFO" key. - It takes somewhat stronger signals to stop the scan in this mode than normal so the squelch may need to be loosened. Weak signals may not even break the squelch. - Sometimes the radio will QRM itself as it switches between 2 meters and 440 and keep stopping when there is no signal. To stop this, try reversing the scanning direction. If this doesn't work, try swapping the frequency that it stops on with another. One of these methods will usually stop the scan... These "keyboard mods" are not my own ideas, but I thought there would be interest in them.... 73 de KA7OEI ---