FT-1000D Mods

Note: these mods were found at various places on the Internet and
I'm just gathering them here - you should proceed with caution 
before taking a soldering iron to your beloved FT-1000  ;-)

General Coverage Transmit Mod

Extended transmit frequency range for YAESU FT1000 -Remove top and bottom covers. Remove top screw on each side which holds front panel to chassis. Pivot front panel down slowly. CAUTION : if you let it go, it will flop down rapidly and probably tear something loose. Behind the meter will be the CNTL unit. It has a metal cover about 4 X 8 inches. Snap the cover off. Look to the top of the unit. You will see JP-3. Remove the solder connection on JP-3.

Filter Mod

The FT1000D comes equipped with additions including I.F. Filters for the 455khz. c.f. The narrowest of these has a 500hz. bandwidth, but no matching filter for the 250hz. bandwidth for the 455khz. I.F. This means that if you select the 250hz. bandwidth filter in the second I.F., it is paired with the 2.4khz. filter in the third I.F. It is a simple modification to have the control section select the 500hz. filter in the third I.F. instead. This modification requires the addition of a switching diode (1N4148, 1N918 etc.) between the select line on the 250hz filter spot and the 500hz. filter. First access the filters on the I.F. board, and clip the diode as indicated for the installation of the 250hz. filter in the manual. Then remove the 500hz. filter, note that the I.F. filter position for the 500hz. filter is the second from the front of the radio. Then solder the diode between the cathode end of the 250hz. select diode, and the cathode end of the diode under the 500hz. filter. This diode should be oriented with the cathode toward the 250hz. select diode's cathode end. Now when the 250hz. third I.F. control pulls the select line low, the new diode will pull the 500hz. filter select line low, selecting that filter in place of the 2.4khz. filter. When you finish this modification you will note that the 500hz. filter reduces the wideband noise, and the "Width" control works when the 250hz. filter is selected. Because of the mismatch in the filter bandwidths, the first few detents on the width control act as an I.F. shift, when the 500hz. filter is offset enough to "catch up" with the bandwidth of the 250hz. filter, the action changes to a bandwidth control. On my radio, the first three detents act as an I.F. shift, and the next three reduce the bandwidth to under 100hz.

Subreceiver Antenna Switch Mod

One other change you may want to make to your FT-1000 is to add an external antenna switch as suggested in the QST review of this radio. This will be useful if you have the BPF-1 option. With this modification you will be able to select the either the main antenna or the BPF-1 antenna for the second receiver by using the front panel switch. The switch added in this mod will allow you to select either the main antenna or the antenna connected to the phono jack for the main receiver, this is useful when using receive loops or converters. I connect a Butternut HF-6V to the BPF-1 and my KLM LPDA to the main receiver. I also plan to add a receiving loop for 80 and 160 connected to the phono jack. This allows diversity reception by polarity, frequency or mode. In order to do this you must select the "E BPF" position on switch S1001 on the R.F. unit and add a switch between one end of S1001 and a pad on J-1007. Remove the covers from the radio and access the R.F. Board as in the manual for setting switch S1001. Remove the three screws holding the connectors for the R.F. board to the rear panel, the six screws holding the R.F. Board down, and unplug the three coaxial cables which go to the R.F. Board. Remember where these cables were connected. Put S1001 in the E-BPF (Enable BPF-1?) position. Lift the board so you can access the bottom. Cut two twenty inch lengths of number 24 wire (or smaller) and solder one end of one wire to the pad under S1001 opposite the switch handle when it is in the E BPF position. Solder one end of the other wire to the pad under J1007 which is near S1001, and is not connected to the center of S1001. Route these two wires through the hole near the center of the rear of the radio. These can then be brought out through the grill on the rear of the radio. I mounted a miniature SPDT switch in the grill, and connected the wires to it. When these wires are shorted the main receiver is switched to the antenna on the phono jack. Replace the screws and connectors, and try everything out. You can then replace the covers. Before implementing this mod, you should read Subreceiver Antenna Modification elsewhere on this site.