MFJ MFJ-1278 User manual

Easy-to follow guide to connecting your new
MFJ-1278/1278T Multi-Mode Data Controller
between your radio and computer
CAUTION: Read all Instructions Before Operating Equipment
MFJ ENTERPRISES, INC.
P.O.BOX 494, MISSISSIPPI STATE, MS 39762, USA
COPYRIGHT © 1990 MFJ ENTERPRISES, INC.

MFJ-1278 & MFJ-1278T Fast-Start Manual
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Introduction
This MFJ-1278 Fast-Start Manual is intended to provide you with the minimum Information ne es-
sary to install your MFJ-1278 or MFJ-1278T "Turbo" Multi-Mode as qui kly as possible. For detail
operation, please see the main instru tion manual.
The differen e between the MFJ-1278 and the MFJ-1278T is that the MFJ-1278T has the 2400 mo-
dem installed. If your MFJ-1278 does not have the 2400 modem installed, it an be pur hased sep-
arately (Model MFJ-2400) and installed by the user. With the 2400 modem installed, your MFJ-
1278 an operate 300 baud, 1200 baud and 2400 bps pa kets.
The Computer Installation se tion assumes that you have pur hased one of the MFJ Starter Pa ks.
If you are not using the MFJ Starter Pa k, you should refer to the main MFJ-1278 Owner's Manual
for Computer interfa e onne tions. However, you may still use the Radio Installation and the oth-
er parts of the Fast-Start manual.
Your MFJ Starter Pa k onsists of terminal Software and a serial able to onne t between the
MFJ-1278 and your Computer.
The Starter Pa ks available are MFJ-1289 for IBM and ompatible Computers, MFJ-1282B for Com-
modore 64/128 Computers and MFJ-1287B for the Ma intosh Computer.
MFJ-1289 Starter Pa k in ludes the MULTICOM advan ed terminal program. MULTICOM supports
multi-gray levels FAX and SSTV re eiving and transmitting. It also supports VGA pa ket pi ture
passing. Other unique features this program gives you are: Auto-Router™ lets you store digipeater
node routes for easy exe ution, Multi-Word™ makes it easy for you to transmit any portion of a
file, Pa ket Multi-Plex™ lets you send and re eive pa ket messages during binary file transfer.
MULTICOM is fully menu driver, and it is very easy to use. It has dedi ated fun tion buffers for
ea h mode of Operation.
MFJ-1289 MULTICOM is highly re ommended if you are using an IBM or ompatible Computer with
your MFJ-1278.
MFJ-1282B for the Commodore C64/128 and MFJ-1287B for the Ma intosh Computers also support
Multi-Gray FAX/SSTV Operation.

MFJ-1278 & MFJ-1278T Fast-Start Manual
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I. INSTALLATION
A. Pow r Supply
Your MFJ-1278 is supplied with an AC adapter. Plug the power supply into a 110 VAC outlet and
plug the 2.1 mm oaxial plug into "POWER" ja k lo ate at the rear of the MFJ-1278.
For operation on AC line voltage other than 110 V AC, you must obtain a suitable AC adapter
whi h will provide 12 VDC at 500 mA to operate your MFJ-1278.
If it is ne essary for you to wire the 2.1 mm oaxial plug for your power supply, wire the 2.1 mm
plug so that the enter pin is positive and the outside sleeve is ground.
B. Comput r Int rfac s
This omputer installation applies to those who are using the MFJ Starter Pa k with IBM and om-
patibles, Commodore C64/128 and Ma intosh omputers. If you are not using one of these om-
puters, or if you are not using an MFJ Starter Pa k, then you must refer to the main MFJ-1278 in-
stru tion manual for omputer installation.
The able supplied with the Starter Pa k must be t used in this installation. If you are not using
the Starter Pa k omputer able to make this onne tion, you should refer to the main MFJ-1278
instru tion manual, Chapter 2 "Computer Interfa ing" to verify that the able you are using is or-
re tly wired.
WARNING: IMPROPERLY WIRED CABLE COULD DAMAGE YOUR MFJ-1278 AND/OR YOUR COM-
PUTER!
1. Conne t the able from the omputer to the MFJ-1278 as follows:
IBM and ompatibles:
Conne t the able end with DB-25 male to the ba k of the MFJ-1278 RS-232 onne tion
mark "RS-232". Then onne t the other end of the able with DB-25 female to COM1 or
COM2 RS-232 port of your omputer.
Commodore C64/128
Conne t the able end with 8-pin TTL onne tor to the ba k of the MFJ-1278 TTL onne tor
marked "TTL", Then onne t the other end of the able to the user port of the C64/128.
Follow the instru tion supplied with the Starter Pa k arefully. Make sure that the able is
wired orre tly and also make sure that the onne tor is oriented properly before plugging
it to the MFJ-1278 and the Computer.
Apple Ma intosh
Conne t the able end with DB-25 female to the ba k of the MFJ-1278 RS-232 onne tor
marked "RS-232". Conne t the other end of the able to the Computer modem port.
2. Load the terminal program by following the pro edure des ribed in the terminal program do u-
mentation.
3. Make sure that the terminal program parameters are set as follows:
Baudrate: 9600 (4800 for C64/128) Wordlength: 8
Stopbit: 1 Parity: None

MFJ-1278 & MFJ-1278T Fast-Start Manual
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4. Turn on the MFJ-1278.
5. Press the "Return" key several times in su ession.
MFJ-1278 will sign-on with the sign-on message and end with the CMD: ommand prompt.
If the sign-on message is garbled, this may be aused by the wordlength and parity of MFJ-
1278 not mat hing the terminal parameters. Remove the over of the MFJ-1278 and dis on-
ne t the shorting Jumper at JMP5. JMP 5 is lo ated next to the battery. After about 2 minutes,
re onne t the shorting Jumper at JMP5.
Note: Removing JMP 5 dis onne ts the memory ba kup battery and resets all MFJ-127S para-
meters to default values. The wordlength and parity default values of the MFJ-1278 are 8 bits
and no parity. This mat hes the terminal parameters äs suggested above in step 3.
6. After the MFJ-1278 has signed on and the CMD: ommand prompt is displayed, type "Display"
and press "Return" key.
MFJ-1278 will display a long list of parameter and end with the CMD: ommand prompt.
The above pro edure verifies that the MFJ-1278 is ommuni ating with your Computer.
C. Radio Int rfac
The first step in onne ting the MFJ-1278 is to wire a able to onne t the MFJ-1278 Radio Port to
the mi rophone or a essory onne tor of the radio. The radio able supplied with your MFJ-1278
has one end already wired with a 5-pin DIN onne tor. You will need to wire the other onne tor
to this able to fit your radio.
MFJ offers optional pre-assembled able to onne t the MFJ-1278 to some radios. Conta t MFJ
dealer or MFJ for more information about these pre-assembled ables. Also available from MFJ
dealer or from MFJ is a "TNC-to-Mi rophone" swit h box (MFJ-1272B) whi h allows you to swit h
your radio between using the MFJ-1278 or using the mi rophone without dis onne ting ables.
Conta t MFJ or MFJ dealer for more information on erning this TNC/MIC swit h box. If pre-as-
sembled able or swit h box is not available you must wire a able to fit your radio.
IMPORTANT: The audio input to the MFJ-1278 must be fed though pin 4 of the MFJ-1278 radio
Port. DO NOT feed audio input though the Speaker ja k in the rear of the MFJ-1278.
The Speaker Ja k is used to onne t a Speaker. It is NOT an audio input.
1. Wire the radio able to MFJ-1278 as shown by the following diagram:
Radio Port Cable

MFJ-1278 & MFJ-1278T Fast-Start Manual
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Note: Spe ifi wiring diagrams for many Kenwood, ICOM & Yaesu radios are shown at the end
of this Fast-Start manual. Che k to see if your radio is listed.
2. On e the able is properly wired, onne t the DIN end to the MFJ-1273 Radio port 1 or Radio
port 2. Conne t the other end to the radio.
3. Other onne tions whi h you may wish to make are:
CW keying:
Conne t a shielded audio able from the KEYING OUTPUT to the KEY input of your radio.
Use the Grid Blo k for tube type radio or Dire t for solid state radio. Wire the keying able
as follow:
CW Keying Cable
FSK Conne tion:
If your HF radio permits FSK Operation, this onne tion an be made thru the use of the
TTL onne tor in the rear panel of the MFJ-1278. Only two lines (Pin-8 FSK and Pin-3
ground) are needed in making the FSK onne tion to your radio. Use the 8-pin IDC onne -
tor supplied with your MFJ-1278 to make the FSK able. See Diagram below.
Note: The polarity of the FSK signal is defaulted to normal on the MFJ-1278. If your radio
requires you to provide a reverse FSK signal you will need to relo ate the shorting jumper
to position 2 & 3 of the JMP 14 header on the MFJ-1278 main board.
FSK Cable
Key paddle:
The able for the key paddle must be a shielded two ondu tor plus a shield for ground.
Use a 3.5 mm miniature stereo plug on one end of the able. The other end of the able is
wired to the paddle, See figure below to wire your key paddle able.
CW Key Paddle Cable

MFJ-1278 & MFJ-1278T Fast-Start Manual
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Speaker Conne tion:
A monitor Speaker an be onne ted to the Speaker ja k of the MFJ-1278. MFJ-280 Mobile
Speaker is re ommended. This is a side tone monitor for both the re eiving and transmit-
ting audio for all modes in luding CW side tone. It also served as a pa ket onne t alarm.
Use a mono or stereo 3.5 mm plug for this onne tion.
Caution: DO NOT feed audio from the radio through this Speaker ja k. Use pin 4 of the Ra-
dio Port for audio input.
Printer Conne tion:
The built-in Parallel Printer Port on the MFJ-1278 allows you to print text or pi tures re-
eived without any spe ial terminal program. If your terminal program does not support
FAX or SSTV pi ture printing to the Computer s reen, printing of these pi tures are possible
through this built-in printer port. An EPSON or IBM graphi ompatible parallel printer is re-
quired.
The printer able ne essary to make this onne tion is a Standard IBM parallel printer a-
ble. You may pur hase this able (MFJ-12) from MFJ Enterprises, In . or from your MFJ
dealers.
5. After properly onne ting the MFJ-1278 to the Computer and to your radio, you are ready to
operate. Load the terminal program and make sure"that the terminal program Parameters are
set as des ribed earlier.
6. Turn on the MFJ-1278. Press the "Return" key several times in su ession. MFJ-1278 will sign-
on with the display of sign-on messages and end with the md: ommand prompt.
II. BASIC OPERATION COMMANDS
The terminal program provided by the MFJ Starter Pa k is designed to allow easier and faster ways
to use your MFJ-1278. Some operational pro edures given by the MFJ-1278 manual may be differ-
ent from the pro edure given by the do umentation of the terminal program. In this ase you
should follow the pro edure given by the terminal program do umentation.
Most of the ommands of the MFJ-1278 are defaulted to enable you to operate in any mode. How-
ever, before you start to use the MFJ-1278, you must first enter your allsign into the MFJ-1278
memory.
To Enter Your Callsign:
Under md: prompt, type: MYCALL xxxxxx <CR> ( xxxxxx is your all sign)
To hange operation mode:
Use the MODE ommand to hange operation mode of the MFJ-1278.
The MODE ommand has the following form:
MODE xx,bbbb,m
where, xx is the operation mode, bbbb is the radio baud rate or speed and m is the modem se-
le ted to be used for that mode. In most ases you will not need to spe ify the modem (
m ) to
be used. The defaulted modem will be mat hed to the mode of operation by the MFJ-1278 au-
tomati ally.

MFJ-1278 & MFJ-1278T Fast-Start Manual
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Examples:
a. To sele t CW mode at 13 wpm, you will type:
MODE CW,13<CR>
If no radio baud rate or modem are sele ted, MFJ-1278 will used the defaulted radio baud-
rate/speed and modem.
b. To sele t 300 baud HF pa ket, you will type:
MODE HP<CR>
MFJ-1278 will be set to operate 300 baud HP pa ket.
. To sele t 1200 baud VHF pa ket, you will type:
MODE VP,1200<CR>
MFJ-1278 will be set to operate 1200 baud pa ket.
d. To enter SSTV mode, type:
MODE TV<CR>
MFJ-1278 will be set to operate SSTV in the 8.5 se ond format.
Abbreviation for all the MODEs are as follows:
MODE VP for VHF pa ket
MODE HP for HE pa ket
MODE VB for VHF RTTY
MODE HB for HF RTTY
MODE VA for VHF ASCII
MODE HA for HF ASCII
MODE CW for CW & Memory Keyer
MODE MC for Modulator CW
MODE FX for FAX
MODE TV for SSTV
MODE AM for AMTOR and NAVTEX
For a listing of the MODE abbreviation, type:
SET<CR>
To verify the present operation mode, type:
MODE<CR>
To hange Radio port, type:
R 1<CR> for radio port 1, or
R 2<CR> for radio port 2.

MFJ-1278 & MFJ-1278T Fast-Start Manual
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For detail of Operation in ea h Operation mode, refer to Chapter 4 of the MFJ-12/8 main instru -
tion manual.
III. TRANSMIT AUDIO LEVEL SETTING
Before you start to use the MFJ-1278, you must set the transmit audio level properly. Radio port 1
and Radio port 2 must be independently set.
A. VHF Radio Transmit Audio L v l S tting:
1. Conne t the radio to a dummy load and listen to the transmission with another radio nearby.
2. With the MFJ-1278 in the VHF pa ket (VP) mode and under the md: ommand prompt, type:
CALIBRA<CR>
3. Type K, then press the spa e bar for the higher of the two tones transmitted by the MFJ-1278.
Note the MFJ-1278 will unkey itself after a few se onds. Re-key, if needed by pressing the K
again to transmit.
4. The transmit audio level ontrols are lo ated on the left side of the MFJ-1278. With a small
s rew driver turn the transmit ontrol fully ounter- lo kwise (minimum).
5. Slowly turn it lo kwise (in rease) until no in rease in audio output level is heard at the moni-
toring re eiver.
6. Rotate the the ontrol ounter lo kwise until the audio Signal on the monitoring re eiver is re-
du ed by half of the maximum level.
7. Type the K key to return to re eive mode.
8. Type the Q key to exit the alibration routine.
B. HF Radio Transmit Audio S tting:
1. Conne t the HF radio to a dummy load.
2. Set the HF radio ontrols as follows:
VOX: OFF
AGC: FAST
Spee h Pro essor: OFF
Mode Sele tor: LSB
Meter Swit h: Power Reading
Speaker Monitor: ON (if available)
Mi rophone Gain: 1/4 Turn
3. Under the md: ommand prompt, type:
CALIBRA<CR>
4. Type K, then press the spa e bar for the lower of the two tones transmitted by the MFJ-1278.
Note the MFJ-1278 will unkey itself after a few se onds. Re-key, if needed by pressing the K
again to transmit.

MFJ-1278 & MFJ-1278T Fast-Start Manual
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5. The transmit audio level ontrols are lo ated on the left side of the MFJ-1278. With a small
s rew driver turn the transmit ontrol fully ounter- lo kwise (minimum).
6. Slowly turn it lo kwise (in rease) until at a point where output power is slightly below the
rated Output of your radio.
7. Type the K key to return to re eive mode.
8. Type the Q key to exit the alibration routine.
IV. RECEIVER AUDIO SETTING
With your radio in the re eive mode, open the squel h ontrol so that a steady hiss is heard on the
Speaker. Set the volume ontrol to the minimum, then slowly in rease it to a point that the MFJ-
1278 tuning indi ator move toward the middle of the display. This is the minimum volume from
your re eiver to allow the MFJ-1278 to opy. Continue to in rease the volume ontrol until the
audio level is about twi e the minimum level.
The DCD Threshold ontrol needs to be set for proper Operation as well. While still listening to un-
squel hed re eiver noise, rotate the DCD Threshold ontrol on the MFJ-1278 lo kwise until the
DCD LED just fli kers with false data arrier indi ations.
Note that DCD Threshold setting may vary for other modes of Operation. Follow the method of set-
ting the DCD Threshold as des ribed in the main instru tion manual under ea h Operation mode.
V. MFJ-1278 2400 PACKET OPERATION
If your MFJ-1278 does not have the 2400 modem, an optional modem (MFJ-2400) an be pur-
hased and installed. Installation is simple; your MFJ-1278 is equipped with all onne tors ne es-
sary to make this Installation without modifi ation or soldering.
With the 2400 modem installed, your MFJ-1278 is apable of operating 300, 1200 or 2400 baud
pa ket. 300 baud and 1200 baud pa ket are not affe ted by the Installation of the 2400 modem.
The addition of the 2400 modem feature will in no way require any internal modifi ation to your
trans eiver.
A. 2400 Pack t Op ration S tup
All default parameters set for 1200 pa ket operation an be used for the 2400 operation. 2400 op-
eration needs no unusual setup or parameter hanges. There are however, some hanges that an
be made later to the MFJ-1278 parameters whi h will enable you to improve the speed the
throughput performan e of the 2400 operation. The "honing" of the parameters may not seem like
mu h, but we have found that at 2400, the MFJ-1278 seems to be more responsive to the TXDE-
LAY, DWAIT, RESPONSE and SLOTTIMES. When using dire t onne ts and good paths, the MAX-
FRAME and PACLEN ommands an be in reased to allow larger pa kets to be moved during ea h
transmission. When returning to the a tive thru-put frequen ies, these two ommands should be
redu ed to their original settings. You may find that if you were using a TXD of 50, then a TXD of
40 will now perform better. The DWAIT an be shortened or lengthened to suit the AGC re overy
time of your radio. For instan e, if you have been running the DWAIT of 16, it may now perform
better at DWAIT of 12 or even 10. The FRACK will appear to exer ise more at 2400.

MFJ-1278 & MFJ-1278T Fast-Start Manual
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2400 really shows its pla e in the pa ket world when used to pass large ASCII, BINARY and PIC-
TURE files. It is always good to use lear frequen y and/or use dire t onne ts to the target sta-
tion rather than going thru a node or digipeater. The reason is obvious. There are few 2400 nodes
at the present time. However, it should be pointed out that implementation of a 2400 node is just
as easy as building and using a 1200 node.
To sele t 2400 pa ket operation, under the CMD: ommand prompt, type:
MODE VP,2400
MFJ-1278 will be set to 2400 pa ket operation. TURBO LED will light. 2400 pa ket an be operated
with Radio Port 1 or Radio Port 2 on the MFJ-1278. Note that if your MFJ-1278 is not equipped
with the 2400 modem, TURBO LED will not fun tion and you will not be able to operate 2400 pa -
ket.
B. R c iv Audio S tting
The MFJ 2400 modem employs automati gain ontrol (AGC) for its re eive audio. The re eive
audio level is preset for proper 2400 operation; no adjustment is ne essary in most ases. If you
set the re eive audio of your radio properly for 1200 operation, then it will be suitable for the 2400
operation also. No adjustment for the re eiver audio on the 2400 modem board is needed.
C. Transmit Audio S tting
Transmit audio on the 2400 board is set by adjusting R38 (next to T2) on the 2400 modem board.
Transmit audio for the 1278T is preset at the fa tory to mat h the audio level of the 1200 modem
on the MFJ-1278 mother board. On e the 1200 and the 2400 transmit audio are set to the same
level, then you may adjust the audio level going into your radio by using the "Transmit Audio" on-
trols on the left side of the MFJ-1278. Note that these ontrols set the transmit audio levels for all
the Operation modes of the MFJ-1278, in luding the 2400 pa ket operation.
When adjusting the transmit audio level please note that the range of R38 is preset by CN-6 head-
er. The shorting jumper on CN-6 header sets range as follows:
CN-6 Jumper Position Transmit Audio Range (no load)
no jumper 50 mV - 60 mV p-p
1 & 2 (default) 100 mV - 200 mV p-p
2 & 3 250 mV - 3 V p-p
VI. AUTOMATIC SIGNAL ANALYSIS (ASA)
The latest firmware (Release 3.4) is installed in your MFJ-1278. A major feature, Automati Signal
Analysis (ASA) is installed in this firmware release. ASA an analyze re eived Signals su h as RTTY,
ASCII, AMTOR and HF Pa ket. It will tell you the speed, data bits and whether or not the Signal is
inverted. ASA automati ally swit hes the MFJ-1278 to the orre t mode on e you a ept the re-
sults of the signal analysis by typing OK and <CR>. As you see ASA is extremely helpful when tun-
ing a ross the Amateur or the Short wave bands. Let ASA help you determine what kind of Signals
you are listening to.

MFJ-1278 & MFJ-1278T Fast-Start Manual
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AUTOMATIC SIGNAL ANALYSIS (ASA) OPERATION
ASA is affe tive in analyzing RTTY, ASCII, AMTOR and HF Pa ket. On e invoked, ASA only takes a
few se onds to analysis the tuned-in signal. On e the result is displayed, user an de ide whether
to a ept by issuing the OK ommand or refuse the result by entering ASA again. On e a epted,
ASA will swit h to the mode it displayed, enter Converse mode automati ally and display data on
the s reen.
To produ e the most a urate result, the MFJ-127S should be set to the HB, HP or HV mode prior
to enter ASA mode. Enter one of these mode by using the MODE ommand. For example, at md:
prompt, type:
Mode HB<CR>
Then at the md: ommand prompt, enter ASA mode by typing:
ASA<CR>
After a few se onds ASA displays the speed and the onfiden e fa tor then it follows with a pause.
After a 5 to 10 se onds pause it will display the speed, data bits and the setting of RXInvert (On or
Off). This is what ASA will swit h the MFJ-1278 to, if the user a epted its result.
The display is in the following format:
<Speed><Confiden e Fa tor>.<Speed><Data Bits><RXInvert On/Off>
A typi al result will look like this:
80 baud 90% Confiden e. 75 baud 7 bits RXInvert Off
After the result is displayed, MFJ-1278 will return to the md: ommand prompt. At this point you
an analysis another signal by typing ASA and press "Return", or if you agreed with the results
then enter:
OK<CR>
The MFJ-1278 will swit h to the analyzed mode, display the mode status and enter "Converse"
mode ready to re eive data.
In the ase of analyzing a 300 baud signal, the MFJ-1278 will prompt the user that the signal ould
be pa ket. If this o urs then the user an enter the following ommand from the md: prompt:
OK Pa ket<CR>
MFJ-1278 will swit h to 300 baud HF pa ket.
If the user does not issue the OK Pa ket ommand and issues just the OK ommand be ause you
know that the signal is not pa ket, then the MFJ-1278 will swit h to 300 baud RTTY. You will enter
onverse mode by typing "K" at the md: prompt and MFJ-1278 begin to opy the signal.
If the ASA result is a 100 baud signal, the MFJ-1278 will prompt the user that the signal ould be
AMTOR. If this o urs then the user an enter the following from the md: ommand prompt:
OK AMTOR<CR>

MFJ-1278 & MFJ-1278T Fast-Start Manual
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When the "OK AMTOR" ommand is given the MFJ-1278 will swit h the AMTOR mode. Follow the
AMTOR operating pro edure to go to any of the AMTOR modes.
If the user does not issue the "OK AMTOR" ommand the MFJ-1278 will swit h to 100 baud RTTY.
Note that if RTTY or ASCII signals are analyzed, and the MFJ-1278 not opying the signal orre tly.
The signal may be en rypted with bit inversion. Most of the time two or three bits of the RTTY
hara ter may be inverted. If the baud rate and the type of signal have been determined, you may
want to try to use the RBitmask ommand to set varies inversion pattern to mat h the re eive sig-
nal. Manual setting of the RBitmask ommand is not ne essary. The RBitmask ommand an be in-
voked when the MFJ-1278 is in the RTTY or ASCII re eive mode by simply issue the "CTRL-U".
On e "CTRL-U" is issued, MFJ-1278 will automati ally y le thru the 32 possible ombinations bit
inversion pattern and try to mat h the en rypted signal. If a mat h an be found, MFJ-1278 will
pre ede to opy the signal.
Note that when using ASA, noise will have major effe t on the degree effe tiveness for ASA.
V. COMMAND UPDATE
The following ommands have been added sin e the printing of the MFJ-1278 4th Edition Instru -
tion Manual.
ASA Mode: Pa ket/ASCII/RTTY/AMTOR
ASA is an immediate ommand. When invoked the MFJ-1278 will analyze in oming Signals su h as
RTTY, ASCII, AMTOR and HF pa ket. It will display the result for speed, data bits and whether or
not the signal is inverted.
When invoked and the MFJ-1278 has analyzed the in oming signal a message will be generated in
the following format:
<Speed> <Confiden e Fa tor>. <Data Bit> <RXInvert On/Off>
ASA will be used in onjun tion with the OK ommand.
On e user a epted the results given by the ASA, MFJ-1278 will sele t the appre iate modem,
mat h the data rate, set the RXInvert and ready to re eive the signal.
ASA is not effe tive in analyzing FAX, SSTV, CW signals and noise.
OK Mode: ASA
OK is an immediate ommand when used in onjun tion with the ASA ommand.
When the results are displayed when using the ASA mode, the user an issue the OK ommand to
a ept the results analyzed by ASA.
Typing OK will ause the MFJ-1278 to sele ted the Operation mode and mat h the speed automati-
ally against the signal being analyzed.

MFJ-1278 & MFJ-1278T Fast-Start Manual
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RXBRIGHT n Mode: FAX/SSTV Default: n = 4
Parameter:
when n = 0, RXBRight assumes the urrent values of TVBreak.
when n = 1 to 9, RXBRight assumes the following TVB values:
n TVBreak
––––––––––––––––––––––––––––––––––––––––
0 assumes the urrent values of TVBreak
1 $42, $26, $28, $2A, $2C, $2F, $32, $35
2 $42, $27, $29, $2B, $2D, $30, $33, $36
3 $42, $27, $29, $2B, $2E, $31, $34, $37
4 $42, $28, $29, $2C, $2F, $32, $35, $38
5 $42, $28, $2A, $2D, $30, $33, $36, $39
6 $42, $28, $2B, $2E, $31, $34, $37, $3A
7 $42, $29, $2C, $2F, $32, $35, $38, $3A
8 $42, $2A, $2D, $30, $33, $36, $38, $3A
9 $42, $2C, $2E, $31, $34, $37, $39, $3A
Note the larger n is the brighter the pi ture. The defaults TVBreak default values are:
TVB $42, $27, $28, $2A, $2B, $2D, $2F, $30
TXBRIGHT n Mode: FAX/SSTV Default n = 4
Parameter:
When n = 0, TXBRight assumes the urrent PIXtones values.
When n = 1 to 9, TXBRight assumes PIXtones values as follows:
n PIXtones
––––––––––––––––––––––––––––––––––––––––
0 assumes the urrent PIXtones values
1 $BC, $98, $A8, $88, $B0, $90, $A0, $80
2 $BA, $B8, $A8, $88, $B0, $90, $A0, $80
3 $B9, $BA, $B8, $A8, $B0, $90, $A0, $80
4 $BB, $B9, $BA, $B8, $A8, $B0, $A0, $80
5 $BF, $BD, $BE, $BC, $98, $88, $90, $80
6 $BF, $BB, $B9, $BA, $B8, $A8, $B0, $A0
7 $BF, $BB, $BD, $BE, $BC, $98, $88, $90
8 $BF, $BB, $BD, $B9, $BA, $B8, $A8, $B0
9 $BF, $BB, $BD, $B9, $BE, $BC, $98, $88
Note that the larger n is, the brighter the default pi ture. The PIXTONEs values are:
PIXtones $B9, $BA, $B8, $98, $88, $B0, $90, $A0
TXDIDDLE ONlOFF Mode: Pa ket Default: ON
TXDIDDLE is whether or not the MFJ-1278 uses a highly effi ient square wave Signal in pla e of
flags during the transmitter delay (TXDELAY) period. When TXDIDDLE is ON, you may sele t even
smaller TXDELAY intervals be ause the square wave presents four times as many transitions as
TXDIDDLE OFF does for your onne tees' re eive syn hronization.

MFJ-1278 & MFJ-1278T Fast-Start Manual
13
TXDIDDLE is defaulted to the ON setting to refle t the in reased effi ien y. However there are a
number of TNCs on the market whi h purport to be AX.25 ompatible but do not re ognize valid
AX.25 pa kets pre eded by the TXDIDDLE keyup te hnique. You may re ognize the need to set
TXDIDDLE OFF if it appears that the Station you're working is unable to su essfully re eive your
pa kets despite your adequate signal.
This failure of some TNCs to re eive TXDIDDLEd pa kets may be a result of some Software arrier-
dete t s hemes. All TAPR and derivative TNCs utilizing hardware-generated arrier-dete t re eive
both TXDIDDLEd and non-TXDIDDLEd pa kets with equal effi ien y.
Note that when TXDIDDLE is OFF, TXDELAYC is irrelevant! Therefore, the a tual TXDELAY yielded
when TXDIDDLE is OFF is equal to TXDELAY × 100 ms plus any AXDELAY time.

MFJ-1278 & MFJ-1278T Fast-Start Manual
14
VII. RADIO CABLE WIRING DIAGRAMS
The radio onne tion information listed in this se tion is believed to be a urate. However, you
should he k the a ura y of this information with the instru tion manual of your radio. MFJ Enter-
prises, In . is not responsible for any ina ura y of the information provided by the diagrams and
harts in this instru tion manual.
Some optional pre-assembled ables to onne t the MFJ-1278 to some radios are available. Con-
ta t MFJ dealer or MFJ Enterprises, In . for detail on erning these ables.
A. 8-pin Microphon Conn ctor:

MFJ-1278 & MFJ-1278T Fast-Start Manual
15
B. 4-pin Microphon Conn ctor

MFJ-1278 & MFJ-1278T Fast-Start Manual
16
C. Handh ld Radio Conn ctors:

MFJ-1278 & MFJ-1278T Fast-Start Manual
17
D. Using th Acc ssory Jack

MFJ-1278 & MFJ-1278T Fast-Start Manual
18
E. Hookup for Sp cific Radios
MFGS. OR
RADIOS
CONNECTOR
TYPE
MIC. AUDIO To
pin 1 of 1278
PTT To
pin 3 of 1278
RX AUDIO To
pin 4 of 1278
GROUND To
pin 2 of 1278
KENWOOD
TR-2500
TR-x600
TH-x1xx
TH-x15
TH-x5
4 pin
5 pin
6 pin
8 pin
HTs
HTs
"
"
"
pin 1
pin 1
pin 1
pin1
Tip-Lg.
Ring-Lg.
"
"
"
pin 2
pin 2
pin 2
pin 2
Sleeve-Lg.
Sleeve-Lg.
"
"
"
Speaker
Speaker
Speaker
Speaker
Tip-Sm.
Tip-Sm.
"
"
"
pin 3, 4
pin 4, 5
pin 6
pin 7, 8
Sleeve-Sm.
Sleeve-Sm.
"
"
"
ICOM 4 pin
8 pin
HTs*
pin 1
pin 1
Tip-Sm.
pin 2
pin 5
Tip-Sm.
Speaker
Speaker or pin 8
Tip-Lg.
pin 4
pin 6, 7
Sleeves
YAESU
FT-208
FT-x09
FT-x3
FT-727
4 pin
8 pin
HTs
HTs*
HTs*
HTs*
pin 2
pin 8
pin 1
Tip Sm.
"
"
pin 3
pin 6
pin 3
Tip-Sm.
"
"
Speaker
Speaker
pin 2
Tip-Lg.
"
"
pin 1
pin 7
pin 4
Sleeves
"
"
*: Some ICOM and Yaesu HTs key the transmitter by ompleting the ground onne tion on the mi-
rophone. If your HT is one that is noted in the above hart, you must follow the instru tion given
in Chapter 3 of the MFJ-1278 instru tion manual.
NOTE: The radio onne tion information listed in this se tion is believed to be a urate. However,
you should he k the a ura y of this information with the instru tion manual of your radio. MFJ
Enterprises, In . is not responsible for any ina ura y of the information listed in the above hart.