Modifications for the Yaesu FT-767
Extended coverage in FT-767 GX 430 MHz modul
Whith this HARDWARE modify, you will be able to Tune your FT-767
RTX from 420 to 449 MHz all mode.
Now You can Receive and Transmit from 420 to 450 Mhz with 10 Mhz
segments by changig position of the switch.
Unplug power cable and all the antenna plugs from the unit
With a screwdriver extract the two screws that fix the UHF
module to the rest of RTX and extract it.
Unscrew the fourth screw of the superior cover.
Localize the TC 9122 CHIPS. They are DPLL Chips oscillators.
Depending of the two versions of this unit (A and B) you
surely 'll notice three soldering pads between two TC 9122
marked A and B.
Clear the three pads from solder and connect them three wire
(if shielded is better).
With a 3 position switch connect A and B wire to the external
pads and central wire to the central pads of the switch.
Now, close and reassemble the unit.
None of wire connected (Switch in the central position):
420 - 430 MHz
Central and A wire connected: 430 - 440 MHz
Central and B wire connected: 440 - 450 MHz
*** NOT POSSIBLE WITH ONLY ONE SWITCH ***
All three wire connected: 450 - 460 MHz
That's All !
It is possible add new combinations and new segments frequency
coverage by cutting one or more pin of Q11 C.I. (the medial
TC 9122 chip) and doing all the binary combinations.
If you see the circuit, A and B connections are connected to pin
3 and pin 4 of the TC 9122,and the central is the ground.
So use pin 2 with the other to have more lower frequencies, or
use pin 5 and/or pin 6 to have more higer frequencies.
See this table for example.
1 Stands for OPEN (Unconnected)
0 stands for CLOSED (connected to the ground).
! Pin ! 2 ! 3 ! 4 ! 5 ! 6 ! Freq. Range !
! ! 1 ! 1 ! 1 ! 1 ! 1 ! 420 - 430 !
! ! 1 ! 0 ! 1 ! 1 ! 1 ! 430 - 440 !
! ! 1 ! 1 ! 0 ! 1 ! 1 ! 440 - 450 !
! ! 1 ! 0 ! 0 ! 1 ! 1 ! 450 - 460 !
! ! 1 ! 1 ! 1 ! 0 ! 1 ! 460 - 470 !
! ! 1 ! 0 ! 1 ! 0 ! 1 ! 470 - 480 !
! ! 1 ! 1 ! 0 ! 0 ! 1 ! 480 - 490 !
! ! 1 ! 0 ! 0 ! 0 ! 1 ! 490 - 500 !
! ! 1 ! 1 ! 1 ! 1 ! 0 ! 500 - 510 !
! ! 1 ! 0 ! 1 ! 1 ! 0 ! 510 - 520 !
The table can continue but only for theory !
The unit is regulated with filters for a close range of Freq.
and so we can go over some frequencies... but this is different
from unit to unit... they aren't all equal !
In addittion, the PLL will doesn't lock the frequency over
a certain frequency !
If I was you, I'd use only the 3 position switch !
Now I'm working to change the frequency value on the display
to have 430-440 visualisation...
OK. That's All for the moment. I hope to receive suggestions,
crytics and comments from someone !
Sorry for my bad English but I can't do better !
FT-767 CAT SYSTEM to a Computer
Some time ago, I read some requirement for help in order to interface
a YEASU CAT SYSTEM to a Computer.
Hereafter, what I'have done to drive an FT-767 with the RS232C of a
DB25S (Computer side) DIN6 (TRCVR side)
/----------------- 3 SI
2 TD -----/////-------
10K NPN 2N2484
V ou equi.
7 GND ------KKKKKKKKKKKKKKKKKKKKKKKKKKKKKKK:95
3 RD --------------- >-----//////------ 2 SO
4 RTS _ / 10K
5 CTS _ V
/ ___ ou equi.
6 DSR _ 8 CD ________ 20 DTR _
This is wired directly on the DB25S connectocTmto suit your needs.
Remember to switch on the CAT first, and to switch it off at the end of
your instructions, if you have to operate manualy the rig later on.
FT-767GX General coverage
Switch off the tranceiver and remove the AC power cable and all other cables
from the rear panel.
Remove the two screws affixing each VHF or UHF band module and slide the
modules out of the tranceiver.
Remove the two screws at the front of the top cover (heatsink).
Place the tranceiver upside down and remove the four screws from the bottom
corners and two on either side (including the carrying handle screws).
Remove the carrying handle and bottom cover.
Remove the seven black painted screws from the rear panel. Then remove the
black outer rear panel.
Remove the ten screws from the inner rear panel and remove this panel.
Remove one screw on either side (rear).
Locate the white molex connectors (one for power and one for the speaker)
inside the rear of the chassis and disconnect them.
Fold the lower half of the chassis away from the upper half, placing a book
of about the same thickness of the heatsink under the bottom half.
Locate the "LOCAL UNIT" board under the metal shield. At this board, locate
switch S01 and change its position. The rig will now transmit
from 1.5 to 30 MHz.
Reverse the disassembly procedure.
VHF Extended range
Turn the battery back-up switch OFF, (you will lose the memories) and turn the
rig OFF. Press and hold key #3 while turning the rig back ON.
In other mods i have seen that it is the #2, so i don't know which is right.?!
VHF band now cover a 10 MHz range (140-150 MHZ).
Memory battery circuitry
Previously the circuitry caused unnecessary drain on the memory battery, resulting in shortened
battery life. There is a kit available for this modification,
which I ordered (free of charge). After reading the instructions
and not being able to even find the components involved, I took
the unit down to LA to the service facility.
DATA IN/OUT Jack audio control modification
This mod was originated by me. Since I have had the unit, I had not used it
for packet because I could not defeat the audio from the speaker
in any way without rendering the audio from the DATA IN/OUT jack
unusable. This jack was supposed to provide direct connection to
the FM modulator and discriminator for packet. It obviously was
affected by the AF gain, external speaker disconnect, i.e., anything
which affected the audio at the built-in speaker. Examination of
the circuit diagram seemed to indicate the audio for this jack
came from the headphone circuit.
When I submitted the unit for the previous mods, I asked about
the possibility of correcting this obvious design error. The
gentleman in charge took all the information, and said he would
advise. I got a call from the technician to clarify the requested
mod, and he advised he wouldn't be able to perform the mod without
factory authorization. After I was notified the unit was ready,
(about 2 months later), I went to pick it up. Along with the
unit was a note saying, "You were right. We hooked the unit up
to a TNC and confirmed the problem. I have reconnected this
jack so that output is independent of AF control. Output is
about 200 MV." which has proved to be more than adequate. The
note was signed by "Rick."
I have run it into a Heath HD-4040,
HK-21, and MFJ 1278T, and it works like gangbusters. What a neat
machine! This one unit serves all my ham radio needs! I no longer
have to hook up my HT just to check into the local board. I now have
it hooked up to the MFJ 1278T, using one port for VHF/UHF into the
DATA IN/OUT jack, and the other port into the PATCH jack, and out
the AUDIO OUT jack, through a Super SCAF, (Switch Capacitor Audio
Filter), to the TNC.
I encouraged "Rick" to publish this mod as a factory-approved mod
and so far, I have not heard anything about it. If you seek this
mod, try to talk to "Rick" and ask for the DATA IN/OUT jack audio
control mod. It is well worth the effort. No, the mod was not
free, and yes, I think it should have been free, but it wasn't,
but the price was very reasonable, I think about $80 for the whole
shebang. 73 and GL.
FT-767GX mod 9600Bd
FT-767GX MODIFICATION FOR 9600 BPS OPERATIONS
- Remove the bottom cover of the FT-767
- Remove the bottom cover (8 screws: 4 underneath, 2 on each side)
- Locate the IF-UNIT board. Is the biggest one of the two cards.
APPROXIMATIVE LAYOUT OF THE IF-UNIT
REAR OF 767
P86 C P7101 J42 DATA IN/OUT
_ _ ____ _ _ +------+
| | (_) |____|(_) | | | |
(D)-> |_| c242 |_| +------+ (_) R383
(A)---------->| | <-------+----scrape varnish and cut
R337 (_) | (| (_) R251 | near the body of R251
Cut here (half position)------> | Q65 |
+----> | | <-- cut here
detail of | | | <-----(C)
R251 | | |
| | |
| | | | | | | | |
| Q07 MC3359 <|
| | | | | | | | |
(B)---> | <----------------- scrape varnish from
() (_) ()c40 the resitance lead
- Once locate the components (jumper (A), resintances R39 (B) & R251 (C) and
the connector P86 (D) connect the point (A) to the point (B) and the point
(C) with the point (D).
Once you have make this simple modification you can connect yor TNC
to the DATA IN/OUT jack, to the rear of the FT-767 as follows.
stereo jack | |-----=---=--
3,5 mm | |-----=---=--/
+------------+ | | |
| | +--- Data in (from tnc)
| +--- data out (to tnc)
Well that's it. You are now ready for 9600 bps operation on your
FT-767GX. If you have problems, reply; I will try to answer your
questions or solve your problems about this modification.
Best 73's de IK2QED - Stefano
| 73 de IK2QED, Stefano | IK2QED @ IW2FPO or IK2QED @ IW2GKO |
| QTH Bovisio(MI) JN45NO | |
In my previous bulletins i have mistake the design of the IF-UNIT
layout indicating a wrong position of the jumper to cut. This was
a cause of trouble to some OM's making this modify.
My particular thanks to F5NWK (Tanguy) wich have notice the mistake.
So I resend the correct modification with the correct layout.
FT-767GX hum modification
name here is jerry, if your 767 has a hum there is a mod that you can
install on the if unit that will take care of this. it is not all that
hard to do once you find the right place.
You will install a ripple filter to the audio amplifier power supply.
First to test to see if you need to do it.
I called yaesu to git the info for the mod and then got the parts from
them. the cost to have them do the mod would have been about $85.00 +
shiping, at first the parts wore going to cost a hole $1.55 w/shiping
but thay gave them to me so the price was right.
Connect a dummy load
Disconnect the mic
Turn on the if monitor
push in the "mox" button and listen if you here a hum you need the mod
You can also plug in the mic, if the hum get's worse do the mod.
You can here it in any mode or band, hf, vhf, uhf.
r1407 2.7 ohm 1/2w resister, L1016 afc coil.
2sd667c (g3406670c) transister, 560 ohm 1/4w (j01245561)
resister, 22uf 25wv (k40149025) cap
At L16 on the if board remove coil L16 and resister r1407
that's it. HAVE FUN.
connect the brown wire from r1407 to the new 560 ohm resister.
connect the "+" side of the cap and the base of the transister
to the other side of the 560 ohm resister.
connect the collector & the emitter of the transister to the two
points on the board whare you removed coil L16.
connect the "-" side of the cap to c290 on the board.
add a jumper wire between the collactor of the transister and the
brown wire on the 560 ohm resister.(i used the trace on the board
for the connection at the collector)
Remove the bottom covers,plastic rear panel then the metal
rear panel,loosen the hinge screws on the front bottom.
Lift the loose card tray to expose the inner circuit boards,there
are two wires that need to be disconnected to do this (dont forget to reconnect
The board we want has some switches on it,(one of them
allows 5 Khz/rev or 10 Khz/rev tuning), locate S 01 and flip the switch.
The radio can now transmit from 1.5 Mhz to 29.999 Mhz
This counter shows the number of hits since the
9th February 2000
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