Yaesu FT847

La Page de G1IVG

Note:

If you only wish to extend the RX and not the TX of the radio have a look at the resistor configuration at position number J4 in your radio (This is shown open in the photo below). if J4 it's fitted remove it. This will open the RX to allow the radio to receive outside the normal amateur bands. If you have a resistor or solder link in the position of J4, then your radio should be locked to RX only within the amateur bands on VHF and UHF.

The configuration of the resistors can done by simply replacing a resistor by soldering a blob of solder to bridge the gap in place of were a resistor should be.

if your not sure in any way about the mods, don't be afraid to ask. I will try to help you the best I can.

General Coverage TX Mods by G1IVG.

Procedure.

Disconnect all cables and connectors from your radio.
Remove the carry handle by taking out the two screws at each end of the handle.
Remove the other two screws on the opposite side of the radio.
Remove the two screws from the rear of the radio, that hold the top and bottom covers.
Remove the remaining two screws from the bottom cover near the front panel.
Now you can remove the bottom cover from the radio.
Place the radio on a clean surface with the top of the radio facing down.
Place the front panel towards you.
Now you should be able to see the Lithium battery to the top left hand side of the PCB.
Look closely and you will see 6 small surface mount resistors just below the battery and to the left.
They are labelled on the PCB as 1,2,3,4,5 & 6 (See photo below).
You need to configure the resistors as in the photo below.
After re-configuring the resistors double check your work and then replace all covers.
Finally you need to make a note of any memory channels you have programmed including offsets etc. As the CPU needs resetting to acknowledge the new configuration.
To reset the radio's CPU make sure the radio is OFF, then press and hold the <FAST> and <LOCK> button's and turn the radio ON. Remember all the contents of the memory channels will be reset and lost.
Also the Automatic Repeater Shift (ARS) will be lost. But all you need to do is, to reprogram the offset from the Menu option No:16 (10mtrs) Menu No:17 (6mtrs) Menu No:18 (2mtrs) and Menu No:19 (70cms)

NOTE:

The photo below shows the radio "AFTER" the modification.

Notes from the photo above:

The photo shows the radio "AFTER" the modification.
"In Place" means that a resistor must be fitted in this location.
"Solder Link" means that you must solder a bridge across the pad no:3, if a resistor is not fitted originally.
"Out" means, remove any resistor from this location.

The coverage of the radio

after the modification.

Receiver (the same as before the modification)

Band Min RX freq. Max RX freq.

H.F. 100KHz 37MHz

VHF (A) 37MHz 76MHz

VHF (B) 108MHz 174MHz

UHF 410MHz 512MHz

Transmitter

Band Min TX freq. Max TX freq.

H.F. 1.8MHz 37MHz

VHF (A) 37MHz 76MHz

VHF (B) 137MHz 174MHz

UHF 410MHz 470MHz

If you decide to carryout the same modification on your FT847, then you do so at your own risk.

This TX modification verified to work on the following serial numbers:

Note: "XXX" replaces the last three digits of the serial number for privacy reasons.

8C020XXX 8F040XXX 8G051XXX 8G060XXX 8G070XXX 8H080XXX 8H090XXX 8I100XXX 8J120XXX 8K130XXX 8K150XXX 8K151XXX 8L160XXX 8N170XXX 9I240XXX 9I250XXX 0D280xxx OE310XXX

E-Mail me your serial number, that the mod is known to work on.

Configuration of Chip Resistors.

Please let me know if there any mistakes in the chart below. As far as I know the information is correct, however proceed at your own risk. colinlowe@jet.es

TX Frequency Range			RX Frequency Range				Jumpers						Remarks
HF	VHF	UHF	HF	VHF(M)	VHF	UHF	1	2	3	4	5	6	FM CH Step	RPT Shift
1	144-146	430-450	0.1-30 50-54		144-146	430-450	X			X	X	X	5/20kHz	0.6/5 MHz
1	144-148	430-450	0.1-37 37-76		108-174	420-512	X				X	X	5/20kHz	0.6/5 MHz
2	140-154	420-450	0.1-37 37-76		108-174	420-512	X					X	5/20kHz	0.6/5 MHz
3	144-146	430-440	0.1-30 50-54		144-146	430-440		X		X	X	X	12.5/25kHz	0.6/7.5 MHz
3	144-146	430-440	0.1-37 37-76		108-174	420-512		X			X	X	12.5/25kHz	0.6/7.5 MHz
2	140-154	420-450	0.1-37 37-76		108-174	420-512		X				X	12.5/25kHz	0.6/7.5 MHz
4	144-146	430-440	0.1-30 50-54	70.00-70.50	144-146	430-440	X	X		X	X	X	12.5/25kHz	0.6/1.6 MHz
4	144-146	430-440	0.1-37 37-76		108-174	420-512	X	X			X	X	12.5/25kHz	0.6/1.6 MHz
5	140-154	420-450	0.1-37 37-76		108-174	420-512	X	X				X	12.5/25kHz	0.6/1.6 MHz
6	144-146	432-438	0.1-30 50-54		144-148	432-438			X	X	X	X	12.5/25kHz	0.6/1.6 MHz
6	144-146	432-438	0.1-37 37-76		108-174	420-512			X		X	X	12.5/25kHz	0.6/1.6 MHz
7	144-148	430-450	0.1-30 50-54		144-148	430-450	X		X	X	X	X	5/25kHz	0.6/5 MHz
7	144-148	430-450	0.1-37 37-76		108-174	420-512	X		X		X	X	5/25kHz	0.6/5 MHz
8	144-146	430-440	0.1-30 50-54		144-146	430-440		X	X	X	X	X	12.5/25kHz	0.6/1.6 MHz
8	144-146	430-440	0.1-37 37-76		108-174	420-512		X	X		X	X	12.5/25kHz	0.6/1.6 MHz
2	140-154	420-450	0.1-37 37-76		108-174	420-512		X	X			X	12.5/25kHz	0.6/1.6 MHz

For HF, 6mtrs and 4mtrs range see table below.

	160m	80m	40m	30m	20m	17m	15m	12m	10m	6m	4m
1	1.800-2.000	3.500-4.000	7.000-7.300	10.100-10.150	14.000-14.350	18.068-18.168	21.000-21.450	24.890-24.990	28.000-29.700	50.000-54.000
2	1.800-2.000	3.500-4.000	7.000-7.500	10.000-10.500	14.000-14.500	18.000-18.500	21.000-21.500	24.500-25.000	28.000-30.000	50.000-54.000
3	1.815-1.890	3.500-3.800	7.000-7.100	10.100-10.150	14.000-14.350	18.068-18.168	21.000-21.450	24.890-24.990	28.000-29.700	50.080-50.400
4	1.810-2.000	3.500-3.800	7.000-7.100	10.100-10.150	14.000-14.350	18.068-18.168	21.000-21.450	24.890-24.990	28.000-29.700	50.000-52.000	70.000-70.500
5	1.800-2.000	3.500-4.000	7.000-7.500	10.000-10.500	14.000-14.500	18.000-18.500	21.000-21.500	24.500-25.000	28.000-30.000	50.000-52.000	70.000-70.500
6	1.820-1.890	3.500-3.800	7.000-7.100	10.100-10.150	14.000-14.350	18.068-18.168	21.000-21.450	24.890-24.990	28.000-29.700	50.000-52.000
7	1.800-2.000	3.500-4.000	7.000-7.500	10.000-10.500	14.000-14.500	18.000-18.500	21.000-21.500	24.500-25.000	28.000-30.000	50.000-52.000
8	1.810-1.850	3.500-3.800	7.000-7.100	10.100-10.150	14.000-14.350	18.068-18.168	21.000-21.450	24.890-24.990	28.000-29.700	50.200-51.200

Download Kantronics KPC9612 Interface diagram

Download SSTV Interface diagram

FT847 Links

You will find other mods and info on these links.

Thomas, DH8GV FT847 Info

Peter, DH1NGP FT847 Supercontrol software

Yaesu FT847 Product Information.

FT847@onelist Message Board

Please send me the URL of any pages regarding the Yaesu FT847, to add to these links.