An IF Based Direct Sampling Panoramic Adapter for the Yaesu FTDX-9000...

FTDX-9000MP + HDSDR + Ham Radio Deluxe....


As an owner of a Yaesu FTDX-9000MP.  I've always felt fortunate to have such a beautiful transceiver included in the line-up of the HF transceivers in my station. It truly is a work of art in design, performance, and quality of hardware.  Nevertheless, there has always been one item that is not factory installed on the FTDX-9000, one that I felt should have been included. That is a connector to obtain a signal from the first intermediate frequency path in the receiver.

I've always enjoyed experimenting with new trends in technology. Recently, with the introduction of moderate priced RTL SDR dongles, and several freeware programs. A useful real-time panadapter has quickly became a common addition to many ham radio stations. Naturally, I also wanted to add that capability to my station as well when using the FTDX-9000. There are methods to implement a panoramic adapter when using a modern transceiver that does not have IF out capability.  However, some of those are cumbersome.   I believe the most effective method is based on a signal directly from a transceiver's immediate frequency after the first mixer.

During a QSO,  I mentioned to a knowledgeable friend, Greg K3EWZ, that I was investigating a way to add a panadapter to the FTDX-9000 platform.  However the problem I was facing, there was no IF out connection on the FTDX-9000.  Greg was kind enough to provide technical guidance about the circuits in the FTDX-9000, so I could implement an IF out signal connector for the FTDX-9000.

A high impedance interface board with filtering, and adequate reverse protection is required to add an IF output signal connector to a transceiver.  A search for information, led me to the web page of Dave Powis, G4HUP (SK).  Dave produces several high quality surface mount Panoramic Adaptor Tap (PAT) Boards, that also includes the necessary low pass filter and reverse protection to fit many different transceivers.  The first IF frequency of the FTDX-9000 is 40.455 MHz. Therefore, I ordered a fully assembled "PAT50M".  The "50" designates, the PAT board includes a 50 MHz low pass filter.  I also ordered a generic socket installation kit. The kit included most everything required to install the board.  However, because of the large size of the FTDX-9000 chassis. It's also necessary to obtain additional Teflon coax to reach between the tap board and a rear mounted SMA connector. I used RG-316.  However, RG-178A is recommended by Dave, G4HUP.  Dave also sells several other interesting items, and has additional technical information about the PAT boards on his website. http://g4hup.com/

Note: Please see the addendum at the bottom of this page for additional comments and recommendations received from Dave, G4HUP, regarding the installation of the PAT board.

The procedure to install the Panoramic Tap Board (PAT) necessitates performing some minor disassembling and alterations to the radio. That includes removing the main receiver (RX-1 board), and drilling several small holes in the back of the radio's rear chassis to install a SMA female connector.  Anyone considering this modification, should obtain a copy of the Technical Supplement (TS) for the FTDX-9000. A PDF copy can be downloaded from several sites. Information in the TS is critical as a reference, and should be kept on hand for review before and during the modification as necessary. The procedure below is specifically for the FTDX-9000MP. There may be differences between the various FTDX-9000 models. Individuals should verify through review of the technical supplement, that the information provided herein is applicable to their particular transceiver. 

The block diagram for the "MP Type" reveals, that after a received signal passes through the mixer circuitry, the first IF 40.455MHz signal is routed through the Mixer Switch Relay (RL-1010). Then, the signal branches out to the input of three relays, the beginning of the roofing filter switching matrix for bandwidths of 3KHz, 6KHz or 15KHz.  It is at that point the first IF signal chain should be tapped, after the first mixer, but before the roofing filter(s). The schematic diagram for the RX-1 Unit is consistent with the block diagram, reflecting that Pin 3 of RL-1010 is physically connected through a branch circuit to Pin 3 of Relays RL-1011, RL-1012, and RL-1013. A review of the RX-1 Parts Layout page in the TS (RX_1-3), shows the physical parts placement of the relays on the component side of the board (Side A) at section G-1.

Another consideration to installing the PAT is to provide the required power to the board.  The recommended voltage is between 8 and 12 volts. The circuit diagram shows an interconnect line designated as RX9, representing that line is high during receive, providing approximately 9 volts.  That line terminates on the component side of the RX-1 board at TP 1014.  The RX-1 Unit Parts Layout diagram shows TP 1014 at section H-3.  TP 1014 is simply a small solder pad. To provide power to the TAP board, a small wire is soldered between the PAT and TP 1014.  That is the only connection that will be made on the component side of the board. The other connections are on the solder side (side B) of the RX-1 board.  The area on the solder side of the board where the connections will be performed are shown on the RX-1 Parts Layout diagram for "Side B", in sections 1-B and 1-D.

To begin, the bottom cover from the FTDX-9000MP must be removed.  Loosening the screws for the side covers helps ease bottom cover removal.  Once the bottom cover is removed, that area reveals several boards, including the two identical receiver boards (if so installed). The RX-1 board of interest is installed in the center of the radio, and is for the (main) VFO A.  To remove the main receiver board. It is first necessary to remove a few other components.  However, before removing any components. I highly suggest that multiple photographs and detailed notes are taken to ensure that adequate information is available to assist when reassembling the radio. The FTDX-9000 has multiple connection points on the RX-1. Some connectors look identical, and making an error is possible, unless there is adequate references beyond what is provided in the technical supplement.

To remove the RX-1 board, working from the front of the radio, there are two metal shields that have a conductive tape bridge between them, one shield is mounted on the VFO A RX-1 board, and the other is mounted to the VFO B RX-2 board.  It is not necessary to disturb the tape. Rather, remove the five screws that secure the shields, remove them as a unit, and place them to the side.  No other components will be removed from the VFO B RX-2 board.

Shields on RX-1/RX-2



The next component to remove is the BPF-1 unit from the VFO A's RX-1 board.   It is mounted under the shield that was just removed from the RX-1 board. The BPF-1 is installed on two pin style header connectors, and is secured by two hexagon fasteners.  First, remove the two hexagon fasteners, and then remove the BPF-1 by gently lifting both sides of the BPF-1 equally to release the board from the connectors.  Once the BPF-1 is removed, the screws that secures the RX-1 board to the chassis are accessible.  Next, remove the screws, disconnect the associated wiring from the on-board sockets, and remove the board from the chassis.

BPF-1 on RX-1



Once the RX-1 board is on the work surface, installation of the PAT board can begin. As described above, there are only three connections that must be soldered to the RX-1 board. One on the component side at TP 1014, and two on the solder side, the IF tap point and a ground.  Referring back to the technical supplement, RX-1 Part Layout Diagram, Side B, at B-1. The layout shows the tap point where the center conductor of the RG-178A coax that is included in the generic socket kit will be soldered to Pin 3 of RL-1010.






Below is a photo of the actual tap point on the RX-1 board. There are the eight pins on relay RL-1010 shown in the photo. From this orientation, the connection is made to the top row, second pin from the right.


      
Once the tap point has been identified, the PAT board should be installed close to the connection point.  I used Velcro to attach the PAT board to the RX-1.  After the PAT board is in position, the RG-178A coax provided in the connector kit can be installed from the RX-1 tap point to the PAT board.  It is unnecessary to solder the shield of the coax cable to RX-1.  Only the center conductor of the Teflon coax cable should be soldered to the RX-1 board.  The PAT board conveniently provides  two grounded solder pads for the coax shield on each side of the signal input solder pad.  Only one is used, and provides flexibility in orienting the cable during installation.  The second connection from the PAT board to the solder side of RX-1, is simply a DC ground. Any convenient attachment point that goes to ground can be used for that connection. 




As noted above, the final connection that involves soldering to the RX-1 board is the 9V+ DC supply point. That wire is soldered to TP 1014 on the component side of the board, and the remaining end is soldered to the PAT board. I found it was easier to solder the wire to TP 1014 before attaching the wire to the PAT board.


Final connection before installing the RX-1 back into the radio is an approximate 28" length of RG-316 to the PAT board's output solder pad. Once complete, the RX-1 board can now be installed back in the radio, while carefully routing the unterminated RG-316 towards the rear panel SMA attachment point.



The installation of the SMA female connector is fairly straight forward. Simply install the SMA connector in the rear panel. Solder the center conductor of the RG-316 to the center pin of the SMA connector, and solder the shield to ground connector supplied in the generic socket kit.  I installed the SMA on my FTDX-9000 in the left corner of the rear panel, which seemed to be the most open area available on the rear of the FTDX-9000's chassis.




The G4HUP PAT board is working extremely well, and am pleased with the addition of an IF out connector for the FTDX-9000.  I am still experimenting with various software pan adapter programs, most recently as shown in the top photo, HDSDR+Ham Radio Deluxe+Yaesu DMU all working together.   Bandwidth coverage is more than adequate. As an example, on 20 meters when using the FTDX-9000 and HDSDR,  I can expand the panadapter to a span of nearly 2.4MHz (13.000MHz to 15.400MHz).  Side by side testing of the main receiver against the unmodified identical sub receiver, does not reflect any adverse affects from the installation of the G4HUP PAT board.

HDSDR on 20 meters utilizing the G4HUP PAT board installed in a FTDX-9000MP...



Second view, showing activity during a recent CW contest at the bottom of the 20 meter amateur band.



ADDENDUM: I received the following useful comments and recommendations from Dave G4HUP, the designer of the PAT board mentioned above.  His comments should be considered when contemplating the addition of a PAT board/IF out connector to the FTDX-9000.

Dave notes, that based on the expansive spectrum of 2.4 MHz I can view with the Panadaptor.  It's assumed that I tapped the IF signal path before the first IF filter.  In doing so, there may be unwanted mixer products visible in the display, and can be identified as signals that tune in the reverse direction of genuine signals that are present in the display.  Although I have not yet noticed the anomaly of erroneous signals using HDSDR and the modified FTDX-9000mp.  I cannot guarantee that will not be an issue for other individuals that perform the modification.  During previous testing by Dave on a Yaesu FT-897. Tapping the IF signal before the IF (roofing) filters, resulted in mixer products that rendered the panoramic adapter display unusable for the user.

Consideration of using a different tap point within the IF signal path may be more appropriate.  He recommends, that if the PAT board input is connected after the IF filter, the visible spectrum is less, but all signals present in the display would be genuine.

In relation to the installation. He recommends not using coax for the input connection to the PAT board. Rather, recommending using some of the fine wrap wire supplied in the connector kit. The wire is lower in capacitance than coax, and reduces the risk of excessively loading the tapped circuit.  Additionally, the PAT board should be mounted as close as possible to the tap point using the double sided adhesive tape supplied in the connector kit.

Finally, he recommends a better coax to use in this type of installation from the PAT board to the SMA connector is RG-178A rather than RG-316, which is 1mm smaller in diameter, and therefore easier to handle.

Update: I recently installed a PAT board in a Yaesu FTDX-1200, because the FTDX-1200 is another radio that does not provide an I.F. out connector on the rear panel.  In that configuration, similar to the installation I performed on the FTDX-9000.  I also tapped the IF path after the first mixer, but before the roofing filter.  Additionally, instead of using coax for the input connection on the PAT board. I used fine wire as suggested by Dave, G4HUP.  That installation also did not reflect any erroneous signals or mixer products on the panoramic display.  The owner of that FTDX-1200 is extremely pleased with the results.
    
73, Jim AB4D.