eview of thu FT-847 
The FT847 is very well packed comes with DC lead, spare fuses hand microphone and
instruction manual I would have to give the writer 20 out of 10 for a superb manual very
easy to read and well illustrated and is also catered for the newcomer to Amateur radio
best manual I have ever read!.
The first impressions I had when unpacking the radio was its size, a bit bigger than I
thought but still very small for what it does a very nice looking radio.The LCD display is
blue very nice appearance with 'S' meter and power meter being part of the LCD display,
you can also adjust the brightness via the MENU ( 1 ) it has a 7 level adjustment.
Now lets get down to the nitty gritty, how well does the radio perform? I will start
with the Receiver but will split the performance up in frequency coverage.
Firstly the RX frequency coverage is:
- 100Khz to 76Mhz ( no gaps ) even though the instruction manual and advertising brochure
has a gap between 30Mhz and 37Mhz.
- 108Mhz to 174Mhz
- 410Mhz to 512Mhz
The Selectivity of the FT847 is
- SSB/CW 2.2Khz
- AM 9Khz
- AM/N 2.2Khz
- FM 15Khz
- FM/N 9Khz
I compared the FT847 receive performance with the following:
TS680 with broadcast band mods done to it.
- ICR7000
- IC551D
- IC251
- FT736R
Lets start from the bottom
100Khz to 500Khz The FT847 is a bit deaf compared to the 5000 and the
3030 but the 847 is better than the TS680.
500Khz to 1.8Mhz Very impressive little or no intermod or crossmod
from strong broadcast signals the AR5000 and AR3030 are slightly better but the 847 is far
better than the TS680.
1.8Mhz to 30Mhz What a HOT radio very impressive runs rings around the
TS680 and is Equal if not better than the AR5000 and 3030 is a pleasure to us on HF !!!
30Mhz to 50Mhz superb is all I can say one of the best receivers I
have played with ( good for us MUF watchers ) bows the ICR7000 and TS680 out of the water
and better than the AR5000.
50Mhz to 54Mhz Being a 6m operator since 1981 this would be the best
radio I have used selectivity and sensitivity is superb, handles strong signals with no
problems there is no comparison with the TS680, ICR7000 and the IC551D the 847 is far
superior.
54Mhz to 76Mhz Still a HOT radio although I did notice from approx
68Mhz to 76Mhz the gain was dropping off a wee bit the AR5000 was better at these
frequencies but the 847 is still better than the ICR7000. also another plus was the 847
behaved its self with VERY strong signals ( we have a 100KW TV station on 62.240Mhz a good
test for receivers!! ).
108Mhz to 144Mhz superb found not intermod from the 20 local FM
broadcast stations ( most are running 10KW plus and 6 stations running more the 50KW!!)
this is a good start, allot of receivers get clobbered by the broadcast stations, the 847
is equal to the AR5000 and is allot better than the ICR7000..
144Mhz to 148Mhz Best 2m radio I have ever played with , the antenna's
being used on 2m are two ten element yagis with masthead preamp and masthead power
amplifier, sat the 847 up against the AR5000, FT736R, ICR7000 and IC251 other than the
AR5000 the 847 was far better than the others and was in parr with the AR5000 ( this is
saying allot for the AR5000!! )
410Mhz to 430Mhz Very good is in parr to the AR5000 and is
considerably better than the ICR7000.
430Mhz to 450Mhz Like the 2m band most impressive best receiver I have
ever played with better than the FT736R and equal if not better than the AR5000, blows the
ICR7000 away!
450Mhz to 512Mhz Still very good I did notice above 470Mhz the gain
was falling of a bit but still no problems ( we here in ZL have utility stations and
Police up on 480Mhz the 847 pulls then in with no problems at all )
The above tests are not overly technical but will give you an idea of the
performance.Also the above tests where carried out with and without the internal preamp (
144Mhz and 430Mhz preamp ) was quiet surprised with the out of band performance with the
preamp turned on!
DIGITAL FILTER/DIGITAL NOTCH AND DIGITAL NOISE REDUCTION.
These are a great feature with the FT847 starting with the Digital filter, there are
two knobs low cut and high cut this can be tailored to your needs this function does take
some getting used to but once you have used it a few times it becomes quiet impressive
Also on CW the digital filter is adjustable through the Menu 10 you can select the CW
band pass filter available values are 25/100/200 and 400Hz this function is amazing and
works very well..
Digital notch: best I have seen this function is fully automatic,
press the D.NOTCH button and offending tone within a spit second is gone! great for
computer birdies on 6m etc!
Digital noise reduction: this can also be adjusted via menu 11 this sets the degree of
DSP noise reduction, the scale is 0 to 15 the higher setting provides more noise reduction
but gives a slight loss of fidelity on the incoming signal this function is also very
impressive.
The FT847 also has a noise blanker that works very well.
Other receiver features are RF gain control, RF amp on/off ( 144 and 430Mhz only ) ATT
switch for all bands, AGC fast/slow switch ( you can not turn the AGC off on the 847 ) IF
shift control, Clarifier control and fast slow button for tuning speed.
Shuttle jog this takes some getting used to, the idea is for quick frequency changing,
if you only move it slightly the frequency only changes slowly the more you rotate the
knob the faster the frequency moves a superb idea for quick band hopping and frequency
changing.
Internal preamp can be switched to a external premamp ( turns the internal preamp off
and puts 12VDC @ 300ma to the 144Mhz and 430Mhz antenna port when the RF AMP switch is
pressed ) this can be adjusted separately for VHF/UHF, both internal and external preamps
cannot be used at the same time unless you have a separate supply rail to your preamp.
FT847 TRANSMITTER
The transmitter of the FT847 is 100w HF/6m and 50w 2m/70cm. there are 2 fans cooling
the transmit stage ( one fan is on all the time and when the ptt is pressed the other fan
starts up for better circulation )
Some of the great features of the 847 are:
- You can monitor your own transmission via the monitor button
- Can set up the audio frequency response via menu 92 ( USB CAR ) and menu 93 ( LSB CAR
using the monitor button ) available values 10 to 15 ( x 10 ) Hz ie 100 to 150 Hz
- Has FM normal and FM narrow ( 9Khz ) on transmit
- Has separate standby outputs for HF, 6M. 2M and 70CM The maximum ratings for these
connections are +24v DC at 100ma.
- Is fully Packet ready both 9600bps and 1200bps
- Adjustable CW delay 10 to 300ms ( menu 9 )
- Adjustable CW pitch ( menu 6 ) 400 to 1100Hz
- Adjustable CW sidetone ( menu 8 )
- Power output is fully adjustable on ALL modes.
- standard repeater offsets for all bands 10m to 70cm can also be tailored for a odd
offset frequency 0.00 to 99.99Mhz.
- Comes standard with CTSS, DCS
- Can set the HF antenna socket for 6m as well ( menu 28 )
- Transceiver can operate cross band repeat ( menu 41 )
- FT847 can operate full cross band eg transmit on one band whilst receiving on other.will
work on satellite mode.
- On air tests have been very impressive with very clean audio.
Out of band transmit mods for the FT847
WARNING! Any modification made is performed at your own risk. Modifications
made could void your warranty.The author assume no responsibility for damage caused to
your radio .
Please check and obey your local regulations before transmitting out side
the licensed spectrum.
Note: There are different versions to the FT847 some may NOT modify.
The Frequency coverage of the 847 TX once modified is:
1.8Mhz to 76Mhz ( no gaps ) WARNING DO NOT TRANSMIT IN THE RANGE 32MHZ TO 37MHZ AS YOU
ARE TRANSMITTING INTO A LOW PASS FILTER AND COULD DO DAMAGE TO THE POWER AMPLIFIER.
137Mhz to 174 Mhz and 410Mhz to 470Mhz
The modifications are quiet simple:
Remove bottom cover you will see the backup battery, on the left hand side their are 6
solder pads numbered 1 to 6 pad one already has a 0 ohm chip resistor across it, short
pads 2 and 3 with 0 ohm chip resistors or just use solder ( not as neat ).
Check pad 6 if it has a chip resistor on it remove it ( if it is not removed the radio
will not go out of band on HF and 6M )
Replace cover , reconnect radio press the fast and lock buttons together at the same
time and turn the radio on this will reset the micro ( you will loose all your memories ).
Testing this mod on a dummy load and watt meter found 1.8Mhz to 30Mhz getting a good
100W right though, from 37Mhz to 50Mhz was also very close to a 100W!!
From 54Mhz to 76Mhz the power did drop off the higher the frequency at 70Mhz getting
approx 20W.
137Mhz to 174Mhz was pretty good with output of 50W!! found the same on 410Mhz to
470Mhz !!
OTHER FUNCTIONS OF THE FT847
The FT847 has allot of additional features I will not go into all of them but will try
and go though some of them.
SCANNING The FT847's Memory system provides a wide variety of facilities which enhance
operating efficiency and convenience. The Memory system stores frequency, operation mode,
bandwidth, repeater offset and tone data, and clarifier information.
- QMB ( quick memory bank ) This is a one channel memory and is handy if you are tuning
around and find something of interest you can pop it into this memory and recall it with
little effort.
- MAIN MEMORY SYSTEM The main memory system consists of memory channels 1 to 99
- ( memory 1 is also the priority channel )
- " HOME " CHANNEL MEMORY I find this very handy, on each band you can programme
a home channel ( your favourite frequency ) eg say when you are on HF you may want your
HOME channel to be 28.885 USB ( the 6m DX chat frequency ) you can be anywhere on HF all
you do is press the HOME button and you go straight to 28.885.
The same thing applies to 6M ( 37 to 76Mhz ) I have 50.110 as my HOME channel on this
band.
ON 2M ( 108 to 174 Mhz ) I have 144.1Mhz on HOME channel and on 70CM ( 410 to 512Mhz )
have 433.1Mhz on HOME channel.
SCANNING OPERATION The FT847 can scan the memories, what memories you don't want
scanned you can "pass" the memory. The scan will operate with SQ open it will
sit at each frequency this can be user adjustable via menu 26.
PROGRAMMABLE MEMORY SCAN The FT847 has one programmable memory scan It is very easy to
operate and works well, like the scan mode you can scan you lower to upper limit with the
SQ open.
MENU SYSTEM The FT847 has a superb MENU system allows customization of many aspects of
transceiver performance by the user. the parameters adjusted via the MENU system are
performance characteristics which do not require adjustment in "real time" by
the user but rather are "set and forget" parameters which optimise the
transceivers setup configuration for the way you like to operate.
The MENU system is easy to activate all you do is press MENU and rotate the SUB-TUNE
control to select the item to be adjusted. Then rotate the MEM/VFO CH control to adjust or
select the parameter to be changed on the MENU item selected.
The FT847 also has a SERVICE MENU for alignment of the radio, I would not recommend
using this function without the service manual and proper test gear.
to access the ALIGNMENT MENU turn radio off press the UP, DWN and FAST keys on the
microphone together while turning the radio on again, the alignment parameter is selected
by rotating the SUB-TUNE dial and the alignment is performed by pressing the MCK/W key.
DOWN SIDES OF THE FT847
Like all radios there are down sides ( you can't please everyone! ) the following are
some of the functions and faults I do not like.
VOLUME CONTROL The problem here is at low volume lets say scale 0 to
10 ( 10 being the loudest ) between 2 and 3 there is a sudden jump, the volume goes from a
low volume setting to a much higher setting with little or no adjustment ( goes from a 2
to a 5 ) .there has been allot of talk on the internet regarding this problem, one of the
fixes is to remove bottom cover, on the right hand side at the back there is the audio ic
, pin 1 of the ic ( closest to the back ) is cut and a 47k 1/4W resistor is put in series
with pin 1. I have tried this modification and have found all this is doing is hiding the
fault not fixing it ( all the mod is doing is cutting the audio down so the volume has to
be turned up a bit more for the same affect ).
CROSS BAND REPEAT Yaesu missed the boat a bit here, the FT847 does
have cross band repeat but one way only, this is a big down fall this means if you say
have 50.150Mhz in one VFO and say 438.840Mhz in the other VFO, when the SQ opens the 847
will transmit on 438.840 but you can not then transmit on 438.840 remotely so the FT847
transmits on 50.150Mhz!
The other downside of the cross band repeat is you cannot scan the RX while in this
mode, this would have been a good feature eg TX on 438.840 and RX scanning say 28.885,
50.100, 50.110, 50.125, 50.200, 144.100, and 144.200Mhz etc.
MEMORY SCAN On memory scan the 847 will not scan in banks, Yaesu could
have had say the 100 memories split up into 10 lots of 10 memories you could then join
them all together to have the 100 memories but you can have the choice of spitting them
up.
If you want to only scan certain memories only you have to "pass" all the
others this makes memory scanning not user friendly.
PROGRAMMABLE MEMORY SCAN ( LIMIT SCAN ) The FT847 only has one limit
scan
I do not think this is enough, Yaesu could have had say a limit scan for each band (
one for HF only, one for 6m, one for 2m, and one for 70cm etc ).
FAN Allot of the FT847 owners have complained about the noisy fan (
one fan runs all the time and when you transmit the second fan starts up ) I personally do
not have a problem with this lets face it most powersupplies have fans and what about
computers they have fans running all the time too!
DUAL RECEIVE The 847 does not have dual receive function but the
priority function does work very well
VOX There is no VOX function on the 847
DTMF ON TRANSCEIVER The FT847 does not have DTMF unless you purchase
the DTMF microphone.
CONCLUSION
If you are looking around for a multimode multiband transceiver with superb receive
performance and compact enough to be used for mobile applications look no further the
FT847 has it all, I think Yaesu has pulled one out of the bag!. It would be by far the
best transceiver I have ever owned, anyone purchasing this radio I am sure would not look
back on there investment.
The FT847 would also be a great choice for the newcomer to Amateur radio everything you
would want all in one well worth considering.
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