The Yaesu FT-847 offers three radios in one -- HF, VHF/UHF and satellite. You get 100 watt output on HF and 6 Meters, plus 50 watts on both 2 Meters and 430 MHz bands. Additional features include: Cross-band Full Duplex operation, Normal/Reverse Tracking, CTCSS/DCS Encode and Decode, 0.1 Hz tuning steps, DSP Notch, DSP NR and DSP BPF, Shuttle Jog Tuning Dial, Carry Handle and Keypad Entry. The FT-847 is also 1200/9600 bps Packet ready.
Product dimensions: 10.2 x 3.4 x 10.6 inches. With MH-31B8 hand mic.
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
basic usage
Q: Does the FT-847 have dual monitor / dual receive?
A: No. Although it will not dual receive, it does does have a priority function as another option. The second VFO is transmit only, designed for satellite work.
model variations
quote "Generally, prior to the 8G05 production run, there was one main problem in the design of the radio: it only had unidirectional CAT control for frequency and mode (i.e., you could only use the PC to command the rig but not to report the rig frequency and mode back to the software on the PC). Beginning with production run 8G05, the radios have bidirectional CAT for frequency and mode (PC commanding the rig, and the rig reporting information to the PC). In the USA (at least), Yaesu offered to upgrade all radios older than 8G05xxxx under warranty, which involved replacing a computer chip in the radio and some other modifications. Many people with earlier rigs took Yaesu up on their offer." , source.
Serial Number Format: Year of manufacture-Month of manufacture-Production Run-Individual Unit number, where the month of manufacture is offset by 2, so "C" means January, "D" means February, "E" means March, and so forth.
Example: 8G051234 = 1998, May (fifth month, or "G"), Production Run 05, unit #1234 in this run.
Example: 8G060144 = 1998, May, Production Run 06, unit #144
modification
The Frequency coverage of the 847 TX once modified is:
1.8Mhz to 76Mhz ( no gaps )
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 !!