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-
- FT470/FT728 frequency coverage mods
- ===================================
-
- There are two ways you can unlock this radio for out-of-band operation.
-
- 1) Turn off power, then press and hold both the UP and DOWN arrows together
- and turn the power back on. This works for the U.S. and Japanese versions
- (FT728).
-
- This will modify the coverage as follows:
- VHF Rx: 140-174MHz
- VHF Tx: 140-150MHz
- UHF Rx: 430-450MHz
- UHF Tx: 430 450MHz
-
- There is a means of making the radio transmit from 140 to 174 if you have the
- courage to open it up and install one jumper that the manufacturer omitted..
-
- Assuming that the radio is open and sitting in front of you, split it in half
- and with the battery facing you locate the lithium battery.
-
- There is a vacant jumper pad just under the edge of the battery at the 11
- o'clock position and just next to the lower right corner of the CPU. This is
- jumper R69 which is not marked on the PC board.
-
- For those with a steady hand and a fine tipped soldering iron, solder a
- bridge across the jumper pad. It is not necessary to remove the lithium
- battery, but it won't matter if you choose to do so.
-
- Close the radio, and you can now transmit from 140-174MHz.
-
- The receiver sensitivity on both the 470 and 728 decreases rapidly above
- 153MHz on VHF but works very well from 430-450MHz on UHF.
-
- Don't forget you need a special licence to transmit outside the amateur bands
- so please check with your local authorities before you try it.
-
- One more thing, if you are wondering what the rubber cap is on the right side
- of the radio, it is for 12v Ext DC. This connector is installed in the
- FT728 only and not in the FT470.
-
- 73 Jim SV0DR @ SV1IW
-
-
- Yaesu FT-470 crossband repeater function
- ========================================
-
- If you turn on the radio with the RPT key depressed, the radio becomes a
- crossband repeater.
-
- Dial up two frequencies you want to crosslink (be sure to pay attention to
- transmit offsets, if any), turn the radio off, depress the RPT key, and turn
- it back on.
-
- The tone encode/decode flags and the -+ flags will be flashing and when
- either band's squelch opens, the other band is moved into the primary
- frequency display and the transmitter keys.
-
- Note that the power output is decreased to LOW power.
-
- Further note: the crossband audio isn't great, probably because it's whatever
- comes out the speaker and gets fed back into the mike. I suppose if you got
- serious, you could create a short interface cable to plug into the top of the
- radio.
-
- Collier Chun NM7B @ WA7ARI
-
- Sysop note: This may be useful for RAYNET purposes, but for other users it
- is a forbidden mode of operation.
-
-
- RESISTOR COMBINATIONS FOR FT470 EXTENDED COVERAGE
- =================================================
-
- Freq range Repeater shift Resistors reqd
-
- 144-146/430-440 0.6Mhz/5Mhz R66/R69/R70
- 144-148/430-440 0.6Mhz/5Mhz R66/R70
- 140-174/430-440 0.6Mhz/5Mhz R67/R69/R70
- 140-174/430-440 0.6Mhz/7.6Mhz R67/R69/R70/R71
- 144-146/430-440 (UK) 0.6Mhz/1.6Mhz R66/R69/R71
- 144-148/430-440 0.6Mhz/1.6Mhz R66/R71
- 140-174/430-440 0.6Mhz/1.6Mhz R67/R69/R71
- 144-146/432-438 0.6Mhz/1.6Mhz R66/R69/R70
- 144-148/430-450 0.6Mhz/5Mhz R66/R72
- Rx 140-174/430-450 0.6Mhz/5Mhz R67/R72
- Tx 140-150
- 140-174/430-450 0.6Mhz/5Mhz R67/R69
- 144-146/430-440 0.6Mhz/7.6Mhz R66/R69/R70/R71
- 144-148/430-440 0.6Mhz/7.6Mhz R66/R70/R71
-
- Of course these modifications are ONLY to be used if you are travelling to
- the country where these frequencies are available and must not be used in
- this country.
-
-