World of Ham Radio 1997

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FT470 YAESU FT-470 INFORMATION Here are some measurements on the Yaesu FT470. Measurements made with regulated 7.2 supply volts. Power output measured with Bird and appropriate slugs. TRANSMIT 2 METERS ------------------ LOW POWER- RF OUTPUT: 1 WATT DRAIN: 400 ma HI POWER- RF OUTPUT: 3 WATTS DRAIN: 700 ma TRANSMIT 70CM ------------- LOW POWER- RF OUTPUT: 1 WATT DRAIN: 550 ma HI POWER- RF OUTPUT: 2.4 WATTS DRAIN: 800 ma RECEIVE ------- As used below, "standby" means squelch closed, no signal received. Note: When using "PRIORITY", "APO" is disabled, but "SAVE" still functions. Note: When scanning, both "SAVE" and "APO" are disabled. Note: With squelch open (received signal), "SAVE" is temporarily disabled. SCAN or STANDBY, ONE CHANNEL: drain: 53 ma SCAN or STANDBY, TWO CHANNELS: drain: 90 ma STANDBY,"SAVE", ONE CHANNEL: drain drops from 53 ma to 10 ma periodically. STANDBY,"SAVE", TWO CHANNELS: drain drops from 90 ma to 10 ma, as above. STANDBY, "SAVE", "APO", ONE OR TWO CHANNELS: same as above. AUDIO, ONE OR TWO CHANNELS: 50 - 150 ma CONTINUED IN FILE FT470.3 FT-470.1 THE YEASU 470 2 METER/440 HANDIE HAS A NUMBER OF UNDOCUMENTED FEATURE THAT CAN ADD TO YOUR ENJOYMENT OF THIS NEAT HT. TWO MODIFICATION CAN EASILY BE PERFORMED FROM THE KEYPAD ITSELF. THIS FIRST ALLOWS THE 470 TO FUNCTION AS A 2 METER TO 440 CROSSBAND REPEATER. THE SECOND ALLOWS YOU TO INCREASE THE VHF RECEIVER RANGE. BEFORE YOU CAN PUT THE 470 INTO REPEATER MODE, YOU NEED TO CONSTRUCT THE FOLLOWING CABLE TO P O---------------L(-----------------------O L L \ / \ 8 OHMS / \ / L L L ----- --- - ' CONTINUED IN FILE FT470.2 FT470.2 AFTER CONSTRUCTING AND INSTALLING THIS CABLE ON THE HANDIE YOU NEED TO PUT IT INTO REPEATER MODE. THIS IS DONE BY SETTING THE 2 METER RECEIVER TRANSMIT FREQUENCIES (THE REPEATER DOES SUPPORT TRANSMITTING AN OFFSET OF THE RECEIVER FREQUENCY). SECOND TURN OFF THE 470, HOLD DOWN THE RPT BUTTON ON THE KEYPAD AND TURN THE POWER BACKIONS! IF YOUR NOT FAMILIAR LOOK IT UP. EXTENDED RECEIVE: INCREASING THE RECEIVER COVERAGE OF THE FT-470 IS ALSO VERY EASY TO PERFORM. TURN OFF THE 470, WHILE HOLDING DOWN THE UP DOWN ARROW ON THE KEYPAD NOW TURN THE 470 BACK ON. YOU HAVE NOW INCREASED YOUR RECEIVER COVERAGE TO 130-180 MHZ. 73'S DE KARL N0IHY @ WB0GDB MSYS @ BBSIHY IN BLOOMINGTON, MN RELAYED BY...N4YJC...CHUCK FT470.3 =============== WARNING!: FT470 shuts down and display goes blank when supply voltage drops to about 4.8 volts. BUT DRAIN CONTINUES AT ABOUT 10 ma. So, there is a danger of over-discharging nicads. Shut your equipment off to prevent this. from WA2NQL TO ENABLE THE FT-470 TO RECEIVE (ONLY) OUT OF BAND ON VHF AND UHF: 1. Turn radio off. 2. Press and hold both UP and DOWN arrow keys, while turning radio on. 3. That's all there is to it! 4. To restore to normal follow the procedure in the manual for resetting the CPU. NOTE: The extended coverage on vhf was apparent but was unable to see any change in the UHF portion. If anyone can figure out why not ... please let me know. FT 470.4 To extend the rx coverage on 2m, simply power-on the ht while holding the up & down arrow keys. FT470.5 Subject: FT470 extended VHF xmit mod file FT-470 mod extended VHF xmit.... Here's the mod for the FT-470. (I have not performed it myself) 1. Remove Cover 2. Remove Lithium battery carefully 3. On left hand side locate some empty vertical pads, one above the other. It should be marked as R-69. There is also a chip resistor R-67 that is just below it to the left a bit. 4. Place a solder jumper across the two R-69 pads. 5. Reinstall the lithium battery. 6. Closeup the Radio. 7. Turn the radio off. While pressing down the up and down arrow keys, turn the radio back on. Note: This mod only opens up the VHF transmit frequency range beyond 140 to 150. The automatic repeater offset will be defeated so you will have to enter the +/- offset yourself. Well, since there's a lot of mod' req's floating around, I thought I'd mention something I discovered while attempting to perform a clone data dump on the Yaesu FT-470. The Yaesu Customer Service Rep' that I called today claimed that the FT-470 *does* have a cloning capability despite the lack of instructions in the manual. Supposedly, the way to get into Clone Mode is to turn on the radio with the F/M key depressed. HOWEVER! If you turn on the radio with the RPT key depressed, the radio becomes a crossband repeater. Try it! 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. 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. One 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. And back to the data dump: I'm hoping to duplicate the efforts of another ham who posted on this network about his success in modifying the FT-411's dump. My problem was that I saw nothing coming out of the clone port when I hit the ^ key. Ideas? p.s. from WB2COY - I can verify that this CrossBand Repeat function works! I made up an audio interface, using a mini and sub-mini phone plug. Tie the grounds together, and connect the center pins through a .01 and 47K resistor in series. Adjust the volume control to about the 11 O'clock position. Works like a charm, for both simplex cross-band and using a repeater on one band and a simplex freq on the other band. You do have to wait for the repeater to drop before you transmit on the simplex freq. This is true for the crossband operation on a Kenwood 721 or Heath HW24 also. 73, Bob - WB2COY @ WB2COY - COYnet ROS 914-485-3393 FT470.7 I have recevied enough enquiries about mods for the Yaesu FT-470 hand held, that I have decided to post what I know. (This is a transcription of a letter that I received detailing the CPU programming jumpers that were found experimentally by Ed Boakes, WB3FLD. Keith, N7HMF) ======================================================================- Dear Keith, A little while ago, I came across a Net News item from you about the Yeasu FT-470 handheld. You asked if anyone knew how to make it receive the public service band just above the UHF amateur band. Well, I've figured out how to do that. However, the bad news is that when you strap the unit for this mode, it only transmits from 430 to 440! Oh, well. I gave you a phone call a week or so ago, but it seemed that we kept missing each other. Anyway, here is what I've learned about the FT-470: I have located a total of eight straps, the four which you had written about, to the left of the lithium battery, and four others located under the flat white cable that interconnects the upper half with the lower half. YEASU FT-470 STRAPS =================================================================---- R69 Vertical, at the 10 o'clock position by the lithium cell R68 Horizontal, to the lower left of R69 R67 Horizontal, just below R68 R66 Horizontal, just below R67 R71 Vertical, the leftmost of three, to the left of the upper corner of the ribbon cable connector. R70 Vertical, the center of three of which R71 is the leftmost R72 Vertical, the rightmost of the three R74 Vertical, to the left of the ribbon cable connector, below the three. (Note that R74 is below an unpopulated capacitor that does not have a C number. =================================================================---- There is no R73, or at least it is not on the circuit board and it is not in the schematic. And, yes, the order of those three is indeed R71, R70, R72, left-to-right. R70, R71, R72 select the mode for the UHF portion of the FT-470. The choices are: UHF CHOICES =================================================================---- R71 R70 R72 Rx and TX Receive only =================================================================---- 0 0 0 430 to 440 Mhz 430 to 500 Mhz 0 0 1 430 to 450 Mhz 0 1 0 430 to 440 Mhz 0 1 1 432 to 438 Mhz 1 0 0 430 to 440 Mhz 1 0 1 220 to 225 Mhz 1 1 0 430 to 440 Mhz 1 1 1 210 to 235 Mhz =================================================================---- R66, R67, R68 and R69 select the mode for the VHF portion of the FT-470. The choices are: CONTINUED IN FT470.8 FT470.8 VHF CHOICES =================================================================---- R66 R67 R68 R69 Rx and Tx Receive only =================================================================---- 0 0 0 0 144 to 146 Mhz 130 to 180 Mhz 0 0 0 1 144 to 146 Mhz 0 0 1 0 1260 to 1300 Mhz 0 0 1 1 1240 to 1300 Mhz 0 1 0 0 140 to 150 Mhz 130 to 180 Mhz 0 1 0 1 140 to 174 Mhz 0 1 1 0 303 to 343 Mhz 0 1 1 1 8AL to 242 Mhz 1 0 0 0 144 to 148 Mhz 1 0 0 1 144 to 146 Mhz 1 0 1 0 1240 to 1300 Mhz 1 0 1 1 404 to 444 Mhz 1 1 0 0 140 to 160 Mhz 1 1 0 1 1260 to 1300 Mhz 1 1 1 0 101 to 141 Mhz 1 1 1 1 1R3 to 158L Mhz =================================================================---- (Note: the receive only ranges are enabled by powering up the unit with the up and down arrow buttons depressed...kjm) When there is more than one combination which has the same frequency range, the difference is the default step size and/or the default repeater offset. Of course, choices that do not match the VCO and filters do not actually transmit or receive on those frequencies. A particularly strange example is that the VHF side of the set can be set to tune from 404 to 444 Mhz, but again, it won't actually lock. Even in the 101-141 mode, the VHF VCO will not lock - this must be for use with some other sort of VCO (It looks like this would cover the aeronautical band rather nicely.) There are two really wierd VHF settings, those for 8AL-242 and 1R3-158L. These must be for use with some other LCD controller - it displays truly unusual and non sequential things when stepped through the "bands". R74 seems to have something to do with something like selecting the IF frequency, or something else like that. When set, it really screws up the VHF reception. My technique for determining these straps is to remove the straps that come in the unit, solder wires to each pad, run the wires out of the unit to a bank of DIP switches, screw the unit back together, and then go through all of the DIP switch combinations. I usually use a stereo microscope and 30 guage wire for this. Since I didn't try powering the unit on with every combination of keys held down for each DIP switch combination, there may still be other secrets possible. Since I was looking for something like receive and transmit from zero to infinity, and I didn't find it, I kept looking until I got bored and wanted to button the thing up and start using it. I determined, from studying the schematic, that there should be a hiddem strapping diode from CPU pin 2 to CPU pin 22. I installed one, but nothing changed. In fact, changing it and powering the unit up did not cause a reset. Therefore, I concluded that this really wasn't a mystery strap, afterall. However, there could be others. I'm trying to get a data sheet for the CPU, from Hitachi, to see if any of the grounded pins are actually I/O pins -- they might be good candidates, particularly if their traces are routed in such a way as to be easily accessible for cutting. CONT IN FT470.9 FT470.9 I've learned that one of the ways to get some of the other, new Yaesu handhelds to go out-of-band, involves dumping data out of the clone port, editing the data, and then dumping it back in. I called Yeasu and asked if the FT-470 could be cloned. They said no, so I ignored them. I haven't figured out how to get it to dump data, but I believe it will accept data. The clone mode is entered by powering up the unit with the F key held down. (It's also a neat way to see all of the indicators on the LCD!) The data must be presented in the ring ("right channel") of a stereo 2.5 millimeter plug which is placed into the mic jack. This is cryptically marked on the schematic, anyway. However, I have no idea what the format for the data should be. If you come across this, I'd love to know. This may be the trap door to getting the rig to receive and transmit in more interesting places. Have fun with your FT-470! Yours Truly, Ed Boakes CAll: WB3FLD =======================================================-- Several interesting things that I have learned since I received this letter... According to the guys at Yaesu, the engineers in Japan appearantly wrote the full UHF rx/tx out of the ROM on purpose. The unit does a very good job as a cross-band repeater. To enable this, turn off the radio, hold the RPT key and turn on the radio. Now, anything heard on EITHER band will be re-transmitted on the other band. There are, however, a few problems. First, there is no real internal path for the audio to get from the receiver to the transmitter, so you either have to modify the radio, to provide a path, or do what I did which is build a short loop back cable connecting the tip of the earphone jack to the tip of the microphone jack like this: <=====----/\/\/\/\/\/\/=====----> 100K This is the way I did it, others I have talked to have used either just a resistor like me or a small capacitor, or a combination. On my radio, this value of resistor gave me a good range of transmitted audio levels by adjusting the volume control. The other small problem is that the radio automatically selects low power on transmit in this mode. This is probably because of the lack of a real duplexer. After looking through the service manual, it became apparent that the small mystery hole on the side of the radio with the rubber plug was originally intended for an external power jack. I have not yet asked Yaesu if they will sell the jack for that spot. I also have no idea why they omitted it. All in all, I still love my FT-470. Its a great little radio.