Modifications for the Kenwood TS-440
TS-440S Digital Audio Modification
NOTICE:
Please be very careful with your transcievers, and we accept no
responsiablity for any damage that may be incurred, and this
modification may, and proably would be cause for any WARENTY to be
DISCONTINUED.
This Modification allows for the Kenwood TS-440s transceiver to have
the data audio on PIN 11 of the 13 pin DIN connector ACC JACK 2. Later
models may or maynot have a correction for this, but my PK-232, or for
that fact NONE of my TNC's would drive the audio to the PIN 11 of ACC
JACK 2. Encountering this problem, and having another H.F. transceiver
I have been using the REMOTE connector, and using an audio input to the
AFSK IN RCA type connector. This would allow me to use the same cable
with my TS-180s also. Anyway this modification moves the wire's from
the AFSK IN to the ACC 2 connector. This should only take about 20 to
30 minutes to preform this change, and most of the time is used up with
the removal, and replacement of the THREE covers of the transceivers
cabinet.
The circuit boards to work with, are called:
DISPLAY UNIT (X54-1870-00) (C/4) This has the ACC 2 JACK.
SWITCH UNIT (X41-1610-00) (M/14) This has the AFSK INPUT.
The eaiest way is to remove these two boards 4 screws hold the ACC 2
JACK, and 2 screws hold the AFSK INPUT board in and they are located at
the rear of the transceiver. If you are interested in following the
SCEHMATIC in your manual, the leads you will be working with are ANI,
and GROUND which is the PURPLE LEADS, and the FSI lead and GROUND,
which are the GREEN leads.
The problem is that when kenwood designed this rig, they brought
the DATA INPUT(ANI) from the ACC2 JACK to connector J25 of the IF UNIT.
This coming in after the Processor, and Microphone Amplifier does not
allow sufficent amplification of the signal, thus very low, or no audio
at all. What this modification does is swap at the rear of the RIG the
FSI, and ANI signals, Which also could be done on the IF UNIT board,
and for some may actually be eaiser. In my case the leads were just a
bit too short to allow this modification to be accomplished on the IF
UNIT.
MODIFICATION
-
Be shure to have on a work bench, and NO POWER APPLIED!
-
Remove the TWO BOTTOM covers, One MAIN cover, and the smaller
cover to the REAR of the transceiver.
-
Remove the TOP cover.
-
Remove the FOUR screws holding the AUTOMATIC ANTENNA TUNER.
-
Place the transceiver on it's side with the BOTTOM towards
you, and the FRONT to your LEFT.
-
Being very careful, remove the antenna tuner and allow it to hang.
-
Remove the TWO SCREWS that HOLD the AFSK INPUT board.
-
Remove the FOUR SCREWS that HOLD the ACC 2 JACK board.
-
Carefully from the inside of the transceiver, pull these TWO
boards out.
-
Near the Bottom edge of the ACC 2 JACK board, is a TWO lead
connettor, unplug this. The leads should be PURPLE.
-
On the AFSK INPUT board, there is a 6 PIN connector, unplug
this. The leads you will be working with are GREEN in color.
-
Note how the PURPLE leads are connected to the connector itself,
and remove these two leads by inserting a very small screwdriver
into the slot on side, and being very gental, push the leads out
one at a time.
-
Now remove the GREEN leads the same manor.
-
Insert the GREEN leads into the 2 PIN connector, the BLAC lead
is the GROUND, and the WHITE or perhaps YELLOW is the AUDIO lead.
-
Insert the PURPLE leads into the 6 PIN connector, noting that
the smaller lead is the AUDIO lead, and it connects to PIN 2,
the other lead, being BLACK goes into PIN 1.
-
Now reassemble in reverse order the BOARDS, and start at STEP
11, and work in reverse to STEP 1.
TS-440 Fan Temperature Modification
I don't know about you, but I don't think solid state equipment needs
to run hot enough to fry an egg on. The fan on the 440 is set to come
on at 50 deg C. That makes the heatsink hot enough that you can only
put your hand on it for about 3 seconds without being in pain.
Looking at the schematic and pondering the situation, I decided that it
would be quite easy to change the "trigger" point for fan operation.
This mod will do just that and not effect the "high-temp-shutdown" mode
that is provided in case the fan dies. Actually, it wouldn't be a bad
idea to make the same sort of mod to that circuit too, but let's just
do this one for now. I'll put out another bulletin on this if I go into
the failsafe circuit.
The fan is controlled by two sensing circuits on the FINAL UNIT. On the
schematic, Q9(1/2) is the failsafe trigger that activates the powerdown
circuit in case the final reaches 80 deg C. It won't normally do this,
even under continuous keydown conditions, unless the fan has failed.
Q9(2/2) is the stage that controls operation of the fan. It is a simple
voltage comparator and therefore can be made to trigger wherever you want.
TH1 is a thermistor with a negative coefficient. That is, when the temp
rises, the resistance goes down. This pulls the - input to Q9(2/2) lower
and lower until it is at or below the 2.26v reference that is present on
the + input of the same stage. At that point, the output flips high and
turns on Q8, thus turning on the fan. By raising the reference voltage
at the + input, the TH1 voltage will fall to the reference voltage sooner
and turn on the fan at a cooler temperature. By clipping the top loop of
R27 on the final unit (2.2k res. that provides reference voltage) and
temporarily inserting a 5k precision multi-turn pot in series with it, I
determined that I liked the way it operated with about 800 ohms extra
resistance in the circuit.
I then installed an 820 ohm fixed resistor in
series with the cut loop. I also put a very small dab of silicon seal
between the new "hung" resistor and the ferrite transformer right next to
it so that there would be no added strain on the remains of R27. The
alternative would be to remove the final unit completely and do the mod
the right way, replacing the complete R27 with a 3k resistor. This was
a step that I didn't really want to perform on a two week old rig. When
you choose your series resistance, remember that the more resistance you
add to it, the sooner the fan will turn on. If you go too high, it will
be on all the time.
This modification brings the fan on at least 10 deg. earlier. By the way,
my only reservation about this mod is the added wear and tear on the fan
unit itself. I have been buying parts from Kenwood for about 10 years now
and they have always seemed remarkably inexpensive. Ordering a spare fan
to have on hand seems like a very reasonable thing to do if you are worried
about it.
Possible cure for TS440 showing dots only on display
The most common reason for the the display to show only dots, is that one
of the phase locked loops is not locked. So take of the top cover. You will
be looking at the IF unit. This board is mounted in a hinged frame. It hinges
on two screws near the front pannel sides. So remove the other two screws
near the final unit instead and hinge the IF board towards you. You now
uncovered the PLL unit.
There are five PLL's on this board. Each one has a pin indicating if its
loop is locked or not. So get out a volt meter and set it for 5 volts full
scale. Now check pin 2 for each of the following IC's. IC18, IC1, IC4, IC9.
Also check pin 7 of IC17. If all the loops are locked, you would see a
steady voltage there in the neighbourhood of 4.7 volts. If any of the
loops is not locked, one of these pins has a voltage well below 1 volt.
Note the IC number so you can look up which VCO you may have to tune a bit
so it will lock again.
IC18 VCO#5 T20
IC1 VCO#4 T1
IC4 VCO#3 T2
IC9 VCO#2 T9
The above are all located on the PLL board.
The VCO for IC17 is actualy one out of four different VCO's selected
on the RF board. Which one of these depends on what band is selected.
If you have display dots on all the bands, then you have no problem
with the PLL made up with IC17. So you only have to adjust either
T1, T2, T9 or T20.
Now here it goes. Make sure you have an alignment tool that isn't to small
or to large for the slots in the slugs in the coils (T1, T2, etc.)
Also, absolutely don't turn any other coil than the one that belongs to the
unlocked PLL. If you do so anyway without a service manual and proper equip-
ment, then you are likely stupid.
Only turn the indicated slug. First turn it 1/4 clock wise and see if it is
ok now. If not, turn it 1/4 counter clockwise and see if it works. I suggest
that you don't try more than one half turn either way. If you think that it
needs to go that far, it likely has an other problem.
If the display dot problem only shows up on some but not all band, send me a
note and I will see if I can help you.
The correct way would be to use a good voltmeter and follow the service
manual for this adjustment. But in most cases, the above will do fine.
I don't work for Kwood, I don't have a 440. Just a service manual for one.
But I did cure some of the above problems.
Undocumented feature
The TS440 is nice. Here's what I've found out about it that isn't in
the operation manual (in some random order):
Diode options: There are a bunch of configuration options controlled by
clipping or inserting diodes on the back of the control board. You get
to it by taking the top and bottom covers off (a bunch of silver
screws), loosening the front panel (4 flat-head silver screws, NOT the
black ones). Then you have:
diode controls in out (cut)
----- -------- ---------- ----------
D65 mode confirmation Morse single beep
D66 display resolution 100 Hz 10 Hz
D67 memory protect none on
D73 CW shift 800 Hz 400 Hz
D78 WARC 24MHx band tx disabled enabled
D79 WARC 18MHz band tx disabled enabled
D80 General Coverage tx disabled enabled
Self-Test: You can run a rather complete test of the control logic by
the built-in "semi-self-test", a series of 56 routines. To run this,
turn the unit on whilst holding the AM and T-F SET switches pushed in.
It changes to the next test when you turn the VFO knob clockwise. Turn
the power OFF to reset the unit.
Test What it does
---- ---------------------------------------------------
0 all positions in display light
1 all segments in display dark
2 all positions in display light
3 all segments in display dark
4 one digit lighted (rightmost)
5 next digit lighted
6 next digit lighted
7 next digit lighted
8 next digit lighted
9 next digit lighted
10 next digit lighted
11 next digit lighted
12 next digit lighted
13 next digit lighted
14 next digit lighted
15 next digit lighted
16 next digit lighted (leftmost)
17 beeper sounds
18 beeper silent
19 all mode LEDs ON
20 all mode LEDs OFF
21 receive
22 transmit
--------------------------------------------------------------------------
The following tests change internal signals. They are most useful if
you are trying to trace the circuits controlled by these signals.
You'll need a s service manual (or at least a schematic) to made reals
sense of these.
23 Band select - all lines high
24 BAND select - all lines low
25 PD select - all lines high
26 PD select - all lines low
27 ENF select - all lines high
28 ENF select - all lines low
29 ENP select - a:ll lines high
30 ENP select - all lines low
31 RES select - all lines high
32 RES select - all lines low
33 CO select - all lines high
34 CO select - all lines low
35 AX select - all lines high
36 AX select - all lines low
these next tests check the outputs of the 8255 parallel port interfaces,
which select several internal functions.
37 (IC2) port A all lines high
38 (IC2) port A all lines low
39 (IC2) port B all lines high
40 (IC2) port B all lines low
41 (IC2) port C0-C3 high, C4-C7 low
42 (IC2) port C0-C3 low, C4-C7 high
43 (IC53) port C all lines high
44 (IC53) port C all lines low
Following display busy lines and scan lines in the rightmost 9 digits of
the display. You will push buttons to cause the digit to change from a
1 to a 0 indicating that the associated button has been pushed.
test bit8 bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0
---- ---- ---- ---- ---- ---- ---- ---- ---- ----
45 LOCK AT Mic UP Mic DN PTT/AT VS1
46 (none)
47 (key scanner)
48 1 6 V/M VOICE
49 2 7 M>V RIT A/B
50 3 8 SCAN XIT SPLIT
51 4 9 M.IN T-Fset A=B dip3 dip4 dip5
52 5 0 CLEAR 1Mhz dip1 dip2 dip6 dip7
53 ENT DOWN UP dip8 dip9 dip10
(the digits 0-9 are on the front panel keyboard; dip2-dip10 are the
segments of S50, the SSB frequency response dipswitch on the rear of the
control unit printed circuit board.)
54 not used
55 not used
56 END
Serial interface
The TS440 has a serial ASCII interface option. You have
to insert two chips into sockets on the back of the control unit circuit
board to take advantage of this. IC54 is an 8251A Uart, and IC55 is a
CD4040 divider. These chips are available from Kenwood together with a
interface manual, or you can buy them at your local chip shop for about
$6.00 or so. When inserted, the transceiver speaks 4800 baud ascii
in/out the 6-pin DIN connector ACC-1 on the rear. The signals are from
the 8251, but are inverted in a 74LS04 and RFI filtered before being
brought out to the world. An interface box with inverter, RFI filter,
power supply, opto-isolator, RS232 level shifters, and power supply is
available from Kenwood for about $49.00, or you can build your own.
(Depending on how much your computer radiates and how sensitive to RF
it is, you may only need 5v, +/-12v, a 74LS14, MC1488, and MC1489.
If your computer has a TTL level serial port, perhaps all you'll need
is the 74LS14. If you're not confident of being able to solve the
possible digital/RF interface problems yourself, the $49 interface
is proably a good buy.)
ACC-1 Serial Interface
pin signal
--- ----------------------------------------------------
1 signal ground
2 data from transceiver
3 data to tranceiver
4 cts to transceiver - computer can throttle output
5 cts to computer - transceiver can throttle input
6 no connection
SSB frequency response dipswitch: located on the back of the control
unit, this adjusts the frequency response of the upper and lower
sideband modulators to compensate for component variations. Changing it
isn't a good idea, since you have to have a two-tone oscillator and have
to reset the carrier suppression adjustment if you do. The service
manual explains this process; I'm including this here so that people who
have been wondering what the dipswitch does won't screw themselves by
flipping switches to see what happens.
A few adjustments you should know
A few adjustments you should know about (read the service manual before
you tweak wildly on these!):
tweaker what it does
------- -----------------------------------------------
RF-VR3 FM Microphone Gain
RF-VR6 FM Deviation - set to 4.6KHz on dev meter
IF-VR2 S-meter zero - set to zero with 50 ohm dummy load
IF-VR3 S-meter S9 - set to S9 with 40dbu input 14.175MHz USB
IF-VR4 Squelch threshold - close at 12 o'clock with
mode = CW and filter WIDE
IF-VR9 CW side tone level - as you like it
IF-VR10 Beep tone level - as you like it
Someone wanted to know what the difference between the DATA connections
on ACC-2 and the AFSK connectors was. On output, none; the AFSK and
the DATA out pin on ACC-2 are connected together, and are fed from the
high side of the volume control - they are receiver audio BEFORE the cw
sidetone, beeper, and voice response unit are mixed in, and should be a
constant level independent of the AF gain setting. The AFSK input is
different from the DATA IN connection; AFSK and microphone signals both
go through the mike preamp and speech processor; the DATA input
bypasses both. The MIC GAIN pot does control all three input levels.
(as a note, you can tap preamped/processed audio OUT of the DATA IN
connection, since it is just a tap on the output of the
preamp/processor. This is also the feed into the FM modulator. But
NOTE that the MIC GAIN pot doesn't adjust the mic gain on FM - there is
a separate tweaker for that.)
TS-440S modification to use antenna tuner
Remove case from rig. Remove (4) screws that holds antenna tuner in place. Next
slide antenna tuner out to get to the coax connections. Remove the in coax
attached to antenna tunerfrom FO connector on filter unit (X51-1340-00). Remove
coax from out connector on antenna tuner and install in FO CONNECTOR ON FILTER
UNIT. Unplug and remove switch unit (X41-1610-00 N-14) from rig.
Remove short wire from antenna connector to PC BOARD. Cut coax on the in
connector of antenna tuner in half and connect cut end to switch unit PC BOARD
Where short antenna wire was removed and shield to ground. Solder other half
of coax to antenna connector and shield to ground, and plug other end into out
conector of antenna tuner. Your still have control of antenna tuner with
auto and thru switch. It works very well. Maybe someone can use this idea.
TS-440S display calibration
I found there was some shift in the reference oscillator
frequency of my TS-440S. This can be noticed and corrected
as follows:
-
Remove the top and bottom covers from thd radio.
-
Do not disconnect the speaker cable.
-
Connect the supplied calibration cable between RF Unit
and PLL unit, as shown in "Kenwood TS-440S Instruction
Manual" on Page 24 in Section 5-8-3.
-
Set VFO A to 10.001.00 MHz LSB and VFO B to 9.999.00 MHz
USB.
-
Pushing the A/B function button, you can have different
audio signals, if that 36 MHz reference oscillator is
miwadjusted.
-
Using a small flat bladed scredriver, adjust trimmer
capacitor TC1, near connector 8 of the PLL Unit (the
location shown in Instruction Manual in the same section
as above) until those audio frequencies from VFO's A and
B are equal.
-
Disconnect the calibration cable and reassemble the
radio. This procedure can be done by ear with good
accuracy without any measuring equipment. WWV is too
weak here in Finland to use it as comparative signal for
the procedured described in "Instruction Manual", Section
5-8-3.
B>Connection of the KENWOOD TS440S to a DATA
Connection of the KENWOOD TS440S to a DATA terminal such as a Kantronics
KAM using the rear ACC2 13 pin jack.
____ 4 3 2 1
GROUND ___ |
|____ 8 7 6 5
|
|___ 12 11 10 9____________
/ |
MIC ____________/ 13 |
| |
| |
\_/ \_/
===== =====
| |
|___________________|
|
|
|
|
PTT
Pins | Application
-----------------------------------------------------------------
3 Data output - not used as the level is very low
the prefered connection is via the speaker output
this also allows fine adjustment of level to
enable best decoding. (A switch on the speaker to
'mute' it when required is a good idea.)
4 Ground - you may have to experiment with these
8 connections to eliminate RF feedback and noise.
12 Here they are all strapped.
9 Mic mute - prevents audio pickup from the mic when
earthed. By connecting to the PTT line as shown
through a diode automatically MUTES the mic when
using data. When the front panel PTT or MIC PTT
are used the microphone is 'live'.
13 Standby - PTT which when taken to ground puts the set
'on air'. By connecting through a diode as shown
doesn't affect the PTT operation but allows auto
mic muting.
The diodes used can be virtually anything, here they are IN4148.
The INPUT audio to pin 11 must be quite a high level. If using a KAM you are
certainly going to have to change the HF LEVEL JUMPER in the KAM. The level
of the KAM as shipped suites connection to the FRONT PANEL MIC but not the
rear connector, you can however correct this with the jumper. People using
the PK232 have complained of NO TX AUDIO, I suspect the level is so low that
only local minitoring will show a level present.
Kenwood Computer Interface Instructions
These Instructions are TS-440 specific, but the basics also
apply to the TS-940, TS-811 and TS-711.
It is possible to save yourself a few dollars and lose nothing
in quality by buying the parts to upgrade your Kenwood radio for
computer control. Just purchase the parts were you find them and
install them using the instructions in the Radio's Manual.
IC 54 is a uPD-8251-AC Serial Communications Interface.
Commonly called an 8251A ($1.89 Mail Order)
IC 55 is a TC-4040-BP 12 Stage CMOS Divider.
Commonly called a 4040 ($0.69 Mail Order)
The IC-10 Interface Kit from Kenwood Contains ONLY these two parts
and less instructions than are in this file. The only thing you are
going to miss, is the $22+ price tag on the IC-10 Kit.
Signals are TTL levels (NOT RS-232)
Baud rate is 4800 (1200 Opt.)
Format is ASCII Serial; 1 Start, 8 Data, 2 Stops
The Baud rate may be changed to 1200 Baud by removing jumper W50
and installing a jumper from the left pad to the center pad as viewed
from the front of the radio. This will become obvious once you have
the radio opened up. Many other Baud rates are possible, just look
at the schematic.
As long as you are in the radio, lift D-60 to enable the
10 Hz. display. The main tuning knob is varing this digit, so
you might as well see it. It also helps when using RIT/XIT as
the RIT/XIT display does not resolve the 0.01 KHz. digit. This
Modification is in the Radio's Book.
Not in the book is the fact that if you lift D-80 and do
an MPU reset, you will be able to transmit on any frequency
between 1.5 and 30.0 MHz. This means you will be able to
work the Mars nets, Etc. Do not transmit out of band. It is
illegal even if it is accidental.
Some computers use TTL levels on their serial ports. If so,
here is a time when you will not have to convert it to RS-232.
The IF-232 Interface from Kenwood is a 1488 and a 1489 chip
in a box. These are an RS-232 Quad Line Driver and Receiver
and are available at Radio Shack for $1.29 Each. Here is an
easy project that will save you a lot over the $69+ Kenwood price
of the IF-232 Interface. The 1488 needs a + and - supply.
Unregulated + and - 12vdc is just fine. Get the +5 vdc for the
1489 by putting a 7805 regulator on the +12 vdc supply. 100 mA.
is about the max you'll draw, so the smallest transformer you
can find will still be plenty large. Don't forget to series up
two of each gate to cancel the inversion that the 1480's produce.
ACC-1 Connector Use a 6 Pin DIN Connector.
(Radio Shack $1.29)
Pin Signal Comments
________________________
1 Gnd Signal Ground
2 TXD Serial Data from Radio to Computer
3 RXD Serial Data from Computer to Radio
4 CTS Computer Ready; (Radio Input)
5 RTS Radio Ready; (Radio Output)
6 No Connection
Pins 4 and 5 may be left Unconnected.
***** Command Description for Kenwood Computer Interface *****
______________________________________________________________
Auto Information
________________
AIn;
The Radio Will Send the Status Info Automatically
Whenever the Operator Manually Varies any Function
on the Radio which is Covered in the IF; Command
Where n = 0 for Auto Info OFF
1 for Auto Info On
The Status Information Will be Sent in the Form :
As defined in the IF; Command
Display Memory
______________
DMnnnn;
This is a Factory Diagnostic Function
and is of no practical use to the operator
The Contents of the MPU Memory will be Read
Where nnnn = MPU Address (0000 Thru FFFF (HEX))
The Contents of the MPU Memory Will be Sent in the Form :
DMnnnn-aabbccddeeffgghhiijjkk;
Where nnnn = MPU Address (0000 Thru FFFF (HEX))
aa~~kk = Hex Number Pairs Of Next 16 Locations
Down
____
DN;
The Frequency or Memory Channel
Will Decrement One Step
Frequency VFO A / VFO B Request
_______________________________
FA;
FB;
The Frequency in the Selected VFO Will be Read
The Frequency Will be Sent in the Form:
FAggmmmkkkhhh; or
FBggmmmkkkhhh;
Where gg = GHz. Value
mmm = MHz. Value
kkk = kHz. Value
hhh = Hz. Value
Frequency VFO A / VFO B Select
______________________________
FAggmmmkkkhhh;
FBggmmmkkkhhh;
The VFO Selected Will be Set to the Frequency Defined
Where gg = GHz. Value (May be sent As 00 or Spaces)
mmm = MHz. Value
kkk = kHz. Value
hhh = Hz. Value
Function Select
_______________
FNn;
The Function Defined Will be Selected
Where n = 0 for VFO A
1 for VFO B
2 for MEMORY
Identify Model Request
______________________
ID;
The Model of the Radio Will be sent in the Form :
ID00n;
Where : n = 1 for a TS-940 (*)
n = 2 for a TS-811 (*)
n = 3 for a TS-711 (*)
n = 4 for a TS-440
Read Information Request
________________________
IF;
The Status Information Will be Sent in the Form :
IFggmmmkkkhhh snnnzrx yytdfcp
Where gg~~hhh = Value as defined in FA Command
s = "+" or "-" Value of RIT/XIT
nnn = Value of RIT/XIT (n.nn kHz.)
z = "0" (Not Used in TS-440)
r = Value as defined in RT Command
x = Value as defined in XT Command
yy = Memory Channel No.
t = 0 for Receive
1 for Transmit
d = Value as defined in MD Command
f = Value as defined in FN Command
c = Value as defined in SC Command
p = Value as defined in SP Command
Lock Knob
_________
LKn;
The Manual Frequency Control Functions Will be Disabled
Where n = 0 for Lock OFF
1 for Lock ON
Memory Channel Select
_____________________
MCxmm;
The Memory Channel Defined Will be Selected
Where: x = Don't Care (Use "0" or Space)
mm = Memory Channel No. (00 thru 99)
Mode Select
___________
MDn;
The Mode Defined Will Be Selected
Where: n = 1 for LSB
2 for USB
3 for CW
4 for FM
5 for AM
6 for FSK
Memory Read
____________
MRnxrr;
The Memory Channel Defined Will be Read
Where: n = 0 for RX VFO
1 FOR TX VFO (Split Channels Only)
x = Don't Care (Use "0" or Space)
rr = Memory Channel No. (00 thru 99)
The Memory Information will be sent in the Form :
MRn rrggmmmkkkhhhdz ;
Where: n = 0 for RX VFO
1 FOR TX VFO (Split Channels Only)
rr = Memory Channel No. (00 thru 99)
gg~~hhh = Value as defined in FA Command
d = Value as defined in MD Command
z = "0" (Not Used in TS-440)
(Note: Four trailing Spaces)
Memory Write
____________
MWnxrrggmmmkkkhhhdzxxxx;
The Memory Selected Will be Set to the Frequency Defined
Where: n = 0 for RX VFO
1 for TX VFO (Split Channels Only)
x = Don't Care (Use "0" or Space)
rr = Memory Channel No. (00 thru 99)
gg~~hhh = Value as defined in FA Command
d = Value as defined in MD Command
z = "0" (Not Used in TS-440)
RIT/XIT Clear
_____________
RC;
The RIT/XIT will be set to 0.00 kHz.
RIT/XIT Down
____________
RD;
The RIT/XIT will Decrement by 0.01 KHz. (10 Hz.)
RIT/XIT UP
__________
RU;
The RIT/XIT will Increment by 0.01 KHz. (10 Hz.)
TS-440S How to have the display showing the 10 Hertz digit.
Illustration captions:
-
Remove 17 screws holding on the bottom and top covers. The bottom
cover comes off, and the top cover is carefully removed and put next
to the radio. It is till connected via the speaker wire.
-
Gain access to the front of the unit by removing two top side
screws and loosening two bottom side screws. This allows the front
assembly to swing open.
-
Remove the shiny silver control board protection plate. This
requires removing two screws on the top and three screws on the
bottom. Lift the plate out completely.
Locate diode D-80 in the bottom left-hand corner. Snip it for
all-band transmit.
-
Now locate D-66 and snip. It adds 10 Hertz readout to your
digital frequency display.
-
Carefully reassemble the control plate using a magnetized tiny
screwdriver to hold the five tiny screws in place. Don't pinch any
wires. Also, close up the front and replace the top and bottom covers
with 17 screws.
-
Connect power. Depress A=B switch and turn on the power
simultaneously. This resets the microprocessor for all-band transmit
and 10 Hz frequency display.
TS-440 with PIN-Diodes
Hello, ts440-owners!
Recently i read about an upgrade for the ts440 concerning the bandswitch-diodes.
Originally, there are simple switching types built in.
For better high level performance i decided to replace
D2,3,4,5,6,7,...23,68 by the ECG553 PIN Diode.
The result was not so doubtless positive. i could not really
confirm an advantage. unfortunately, i have no measuring
equipment for determining the intercept point.
But on 40m , where i sometimes have problems using a 160/80/40/30/20m
5-band fullsize dipole, i still suffer intermodulation effects.
I can not really say, if it is much better after the replacement,
but i'm sure, it isn't worse (hi).
Some remarkable progress was the usage of the built-in tuner
in the receiving pass. that really helped espacially on the 10mc band
to overcome the problems of interference.
But best results and a final solution i found in using an external
preselector as described in the cq-dl several times.
That really did it!
Of course you need to add on to cinch connectors at the rear panel.
It is no real problem.
so, my advice:
dodn't modificate the diods or use of the tuner for reception.
The result is too poor compared with that of an external
preselector.
TS-440S operation with the MC-85
With some TS-440S transceivers, insufficient modulation may
occur when the MC-85 compression switch is turned on. This
may be caused by too much of a voltage drop across resistor
R172 on the IF unit of the transceiver . If this is found to
be the case, change the resistor from 1K ohm to 100 ohms.
Required part
100 Ohm, 1/6 Watt resistor.......RD14CB2C101J
PROCEDURE:
-
Disconnect the power supply and antenna from the transceiver.
-
Using a #2 Phillips screw driver, remove the 9 screws
from the top cover of the transceiver. Remove the cover
and unplug the speaker wire.
-
Locate resistor R172 on the component side of the IF
board (Figure 1).
-
Using a #1 Phillips screw driver, remove the 7 screws
that secure the IF unit to the chassis of the
transceiver.
-
Pull the board up and rotate it towards the front of the
transceiver to expose the foil side of the board.
-
Desolder and remove resistor R172 from the board.
-
Install and solder the 100 ohm resistor in place of
R172.
-
Assemble the transceiver by reversing steps 1 - 5.
This modification may be covered under warranty.
Time required for this modification is 0.5 hrs or less.
TS-440S notch filter low frequency improvements
The low frequency attenuation characteristics of the notch
filter can be improved by reducing the input level to the
notch filter chip (IC1). To compensate for the loss of input
level, the amount of negative feedback to the audio
amplifier (IC7) will need to be reduced. This modification
is already incorporated in all models beginning with serial
number 704XXXX.
Required parts:
120K Ohm, 1/6 Watt resistor ........ RD14CB2C124J
390 Ohm, 1/6 Watt resistor ........ RD14CB2C391J
-
Disconnect the power supply and antenna.
-
Using a #2 Phillips screw driver, remove the 9 screws
from the top cover. Remove the top cover from the
transceiver and unplug the speaker wire.
-
Locate resistors R86 and R229 on the component side of
the IF board (Figure 1).
-
Using a #1 Phillips screw driver, remove the 7 screws
that secure the IF unit to the chassis of the
transceiver.
-
Pull the board up and rotate it towards the front of the
transceiver to expose the foil side of the board.
-
Desolder and remove both resistors from the board.
-
Install and solder a 102K ohm resistor in place of R86.
-
Install and solder a 390 ohm resistor in place of R229.
-
Assemble the transceiver by reversing steps 1 - 5.
This is an optional change that may not be performed under
warranty.
Time required for this modification is 0.5 hrs or less.
TS-440S protecting Q33
If pin 7 (RL) of the remote connector is accidently
connected to ground, current from the 14 volt line (14L)
will damage transistor Q33 on the IF unit. This will prevent
the radio from transmitting. To protect Q33, a 4.7 ohm
resistor should be installed in series with the RL line on
the foil side of the IF board. In the event that pin 7 is
connected to ground, the resistor will open, but the
transceiver will still be capable of transmitting.
Required part:
4.7 Ohm, 1/6 Watt resistor ........ RD14CB2C4R7J
-
Disconnect the power supply and antenna from the
transceiver.
-
Using a #2 Phillips screw driver, remove the 9 screws
from the top cover of the transceiver. Remove the cover
and unplug the speaker wire.
-
Locate connector 19 on the IF unit.
-
Using a #1 Phillips screw driver, remove the 7 screws
that secure the IF unit to the chassis of the
transceiver.
-
Pull the board up and rotate it towards the front of the
transceiver to expose the foil side of the board.
-
On the foil side of the board, locate the trace that is
connected to pin 3 (brown wire) of connector 19.
-
Using a craft knife, cut the trace comming from pin
three so as to open the foil trace.
-
Solder the 4.7 ohm resistor across the now open trace
(i.e. in series with the trace).
-
Assemble the transceiver by reversing steps 1 - 5.
This is an optional change that may not be covered under
warranty.
Time required for this modification is 0.5 hrs or less.
TS-440S Case Screws binding in the heat sink
Kenwood U.S.A.
Service Bulletin Extract
Amateur Radio
Number: SB950
Date: 01/20/89
Occassionally a case screw that fastens to the heat sink
of the TS-440S will cross thread or bind when it is being inserted or
removed. Binding may be caused by tooling marks on the screw or by
burrs on the tapped threads in the heat sink. When a screw starts to
bind, DO NOT TRY TO FORCE IT! as this may cause the head to shear
off. If the screw is being removed and it starts to bind, return the
transceiver to KENWOOD. Do not make attempts to remove the screw. In
addition, if a transceiver is being brought to you with a scrw sheared
off, return the unit to KENWOOD. Do not attempt to drill out the
screw.
If a screw starts to bind when it is being installed,
carefully back it out. Inspect the screw for marks or burrs and
replace it if it is questionable. Since the threads in
the heat sink may be causing the screw to bind, they should be
cleaned by running a 3 x 0.5 mm tap into each hole.
The tap is inexpensive and can be obtained at may of
the larger hardware stores.
To avoid cross threading, make sure the covers are properly aligned
when they are being installed. Proper alignment means that there
is a clear path for the screw to turn into the heat sink.
This assures that the screw does not rub against the case and
result in it turning into the heat sink at an angle.
TS-440 RX Audio Mods
Here's some easy modifications to improve the rx audio fidelity of
Kenwood TS-440's. All references below are to the IF board
component designations.
-
Increase C60 to a .47uf or 1 uf. This will increase low frequency
response on all modes.
-
Decrease C51 to .01 uf. This will increase high frequency response
on SSB/CW.
-
Try removing R263 (tacked on the bottom of the board on my early
production unit). This will lower in amplitude the audio coming
out of the detectors and improved the smoothness (a real technical
term) of the audio, especially on AM signals.
And, of course, I take no responsibilty for anything you do to
your radio. Be careful. The IF board on the 440' is about the easiest
one to get at.
TS-440S SSB Power-adjustment
From: PA3FKO@PI8ZWL.#OVL.NLD.EU
Hello TS 440 user..
The last few weeks I've seen questions of how to make the power in SSB mode for the TS440S adjustable without changing the Mic-Gain. It's a very easy job to do.
Take off the top cover of the rig.
At that moment you have a sight on the first unit (IF-Unit)
Than you have to look for Diode 49.
You will find Diode 49 at about 5 CM from the backend of the unit and about 6,5 CM from the leftside of the unit.
Just next of C138 and between plug 38? (red/orange wires) and plug 26 (black-cover/blank wires)
Just cut that Diode 49,bend one part a little away and leave the part's where they are. It's the best way to do I think.
Replace the topcover.
From now on it is possible to adjust only the power in SSB mode by just turning the CARRIER Control at the front of your rig and leave the Mic-gain for where it is.
Turning counterclock will minimize the power until a 20mW or something like that.
Because most TS440 users have'nt used their carrier control that much I think it's better to pull off the MIC/CAR knobs and spray some contact cleaner in the shafts. (I know,it's not the best way).
When you switch your rig into the CW mode you can adjust the power in what you like,switch the mode in to USB or LSB and if it is correct the power will not come above the level that what you have adjusted in the CW mode.
Just simple , is'nt it?
Of course you will do this all in your own responsibility because I won't take any!!! Agree?
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