An understanding of the Sherwood List...

On a recent afternoon, I was monitoring a conversation between two amateurs on 40 meter phone. They were discussing various transceivers that are on the market, weighing which one is better.  As I followed their discussion, one of them excitedly boasted, "Well my radio, the Elecraft K3 is the best radio ever made, it really blows away all other radios costing so much more!"  The other person inquisitively asked, how did you reach that conclusion?  He responded, "I read it on the Sherwood list, only that computer radio...the Flex 6000 rates higher, which isn't a real radio. My K3 beats all the other ones costing so much more than my Elecraft!"

I laughed, first for hearing a grown man become so excited over a radio. Second, because he was so proudly making questionable claims. I thought "better for what"?  In reality, it appears he does not have an adequate understanding of the test data (Sherwood Receiver Test Data) provided by Rob Sherwood, NC0B, and the minimal implication that high narrow spaced DR3 figures have, except under exceptional demanding conditions when using CW.  I appreciate the service Rob Sherwood provides, both because it gives valuable information to the amateur community, and it serves as an independent data source beyond what is published by the ARRL/QST.

Nevertheless, I routinely hear the type of misleading discussion noted above on the amateur bands. Many times, I've heard individuals continue to incorrectly cite the implication of the data provided on the Sherwood list.  It seems, many amateurs continue to relying heavily on the specific Third-Order Dynamic Range Narrow Spaced figures. Rationalizing, whatever radio is at the top of the list, it must be there because it is so much significantly better in all aspects than anything ranked lower.

However, there are many more factors involved in determining which certain transceiver is best for the individual.  Moreover, I note that many of the transceivers that show exceptionally high narrow space DR3 numbers, do not always show an equal level of performance for wide spacing.  A transceiver with higher narrow spaced DR3 figures, although better for the reception of CW signals during crowded band conditions, does not necessary make it a better transceiver for SSB.  A transceiver that has higher wide spacing DR3 numbers, may be a better choice for someone that routinely operates phone.  I suggest reading the document, Choosing a Transceiver Far from Simple by Rob Sherwood.

Rob Sherwood and I belong to the same Yahoo group for the Kenwood TS-990S.  I have read a few of his responses to individuals seeking his advice about certain transceivers, and which one is better.  Highlighted below is a recent typical response I've read from him.  I believe it clarifies his position, and shows his opinion, that somewhat minimizes the importance of specifically high narrow spaced dynamic range figures for the transceivers presented on the table.  Except under certain operating conditions, such as CW contesting or working a CW DX pileup, the higher narrow spaced DR3 figures are not that significant for routine operation.  Hopefully, sharing his response here will give others a clear understanding, that most modern transceivers with good but lower narrow spaced DR3 figures, usually are fine for day to day operating.

NC0B -"The first thing to consider is what modes do you operate and what is the minimum performance needed for normal casual operating.  For SSB I would say 75 dB is adequate most of the time. For CW I would say 85 dB is adequate most of the time. I would guess the 1200 I tested had a roofing filter that was somewhat wider and maybe off center. In any case the DR3 was 6 dB worse on one side than the other. On SSB much of the time adjacent channel splatter from a station 3 to 5 kHz away will be worse than the dynamic range of the radio. When would one prefer really large DR3 numbers?  In a CW DX pile-up or CW contest.  Also having really good phase noise (RMDR) would be really important on Field Day or your equivalent in Europe.  The 3000 has phase noise issues on transmit. If you got a good deal on a radio and it is performing well for whatever your operating habits are, then just enjoy the radio. My two main radios are an old IC-781 with a DR3 of about 75 and a TS-990S which has an RMDR of 87 to 98. I enjoy both radios and they perform fine in the CW and SSB contests I operate. A K3S might be better, certainly on Field Day, but I prefer large radios with really good receive audio.  They suite my needs which is all that matters.



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.  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.

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.


I've been altering my station for the past two years, seeking improvement in operability and modernization, while retaining a bit of nostalgia operating.  I believe I am nearing a plateau period in regard to my station equipment.  Previously, I began assembling a vintage Drake 4-Line station to use by acquiring a pair of non-operating TR4C's.  I now have a complete operational Drake station consisting of a TR4C transceiver, RV-4 remote VFO, AC-4 power supply, and L-4B amplifier (photo below).  Unfortunately, one of the TR4C's I acquired was in such poor condition, repair was not feasible.  I donated that radio for parts to Ron Baker, WB4HFN.

Recently, I also added a fully optioned Yaesu FTDX-3000D to the station. The FTDX-3000D is one of Yaesu's most recent offerings and reports have been good. That rig will be dedicated to mostly digital modes of operation. It seems well suited to that task as it provides built in decoding.  Moreover, it integrates well with the Ham Radio Deluxe software and DM780, the main control/logging/digital program suite used in the station.

In the immediate future, beyond operating I visualize that most of my efforts will be spent on antenna projects and additions to the station's operational aids.  Currently, I am assembling the components required to install an IF out jack in a Yaesu FTDX-9000MP and a Yaesu FT-1000mp Mark V. Tapping the intermediate frequency chain will facilitate the addition of a real time pan adaptor to those transceivers.  I've been experimenting with some of the improved RTL dongles from, and some of the freeware available from various sources.  That technology appears promising to suit my purposes.


ARRL Centinnal

Today,  I received a surprise in the mail commemorating my participation as a W1AW/4 station last year, during the American Radio Relay League's 100th Year anniversary QSO party.  It was fun working the event and an honor of being the sought after "DX" station for once.  During the week, I logged 1406 QSO's for the state of Virginia...73.

Equipment Sale

Through the years, I have acquired a collection of amateur radio gear in very good condition.   I've decided to reduce the amount of radio gear I own, and am offer the following gear for sale from my non-smoking home. If you have interest in any of this equipment and are located within the lower 48 states of the U.S., please email me direct at

1. **Sold** Late production Yaesu FT-1000D.  This original factory FT-1000D (8Y serial number), was purchased new by a friend in 1999. The serial number indicates it was produced in November 1998, a near end of production unit. Most all the 1000D's I've seen for sale have a 1993 or earlier production date.  I acquired this one in 2000.  The radio is in very good operational condition and makes full power (200 watts). Frequency coverage is HF only.  It's clean and cosmetics are good. It has fairly low operational hours because it was never my main HF transceiver.  Included is the original box, manual, unused hand microphone, and everything else that was included with the radio from Yaesu when it was purchased new.  It does not have the only two available options for the FT-1000D, which are two additional CW filters (main and sub receiver). Those can still be purchased from International Radio if desired.  I am asking $1450 shipped and insured within the lower 48 USA.

2. Yaesu FT-1000mp Mark V.  This FT-1000mp Mark V (3L serial number) was purchased new in late 2003. It served as my main HF transceiver for about a year, until I went QRT in 2004 due to a move.  In 2008, I again became active and began using this radio for a short period of time.  An additional transceiver was also purchased at that time, and the Mark V was then relegated to performing SSB duty driving a Quadra amplifier. When using this radio, I receive unsolicited favorable comments about the transmit audio. This one is in very good cosmetic and operational condition.  It does have the common display delay issue (it takes a few moments for the display to turn on if the radio is not used often). However, Yaesu indicates that is "normal" operation to protect the display during cold starts.  Frequency coverage is HF only.  It also includes the follow installed options; two 2.0 KHz SSB filters, and a 70 Mhz noise reduction board purchased from International Radio.  I am asking $1575 shipped and insured within the lower 48. Included is the original box, manual, unused hand microphone, FP-29 power supply, and everything else that was provided by Yaesu when the radio was purchased new. 

3. **Sold** Yaesu FT-840.  I am the original owner of this Yaesu FT-840 (4D Serial Number). The radio is in very good clean condition, both operationally and cosmetically, but it does have a few small minor nicks on the cabinet.  I put it on the air, and signal reports are good with full output on all bands.  It would make a great starter rig for a new ham on a budget, or use for field day or other portable operation.  It was recently modified to eliminate the danger caused by the failure of the 3 watt resistor, R2213, a common problem in the FT-840.  That resistor has been replaced by a 30 watt chassis mount resistor.   Included is the original box, manual, a hand microphone that looks near new in appearance, and the power cable with spare fuses. Asking $325.00 shipped and insured to the lower 48.  

The OCF antenna...

During the past several months, I constructed and began experimenting with an OCF type antenna (180/90 foot elements + 6:1 balun) feed with coax at 70 feet, versus a 540 foot diameter square loop antenna mounted at 35 feet, fed with 600 ohm ladder line. I had it mounted with the ends facing NW/SE.  I have concluded, the loop antenna out performs the OCF antenna and has shown to exhibit greater gain on the low bands of 40-80-160 meters.  Signals from the OCF antenna have consistently been down several S units on both receive and transmit.  Only on the higher bands does it begin to become comparable.

Nevertheless, I enjoyed experimenting with that antenna, but I have not found any real advantage to keep the OCF antenna operational at my station.

The next antenna I am planning as an experiment will be a multi-element inverted V dipole.  I don't currently have an antenna for the 30 meter band, so I will include elements for that band.  Considering a 4 band configuration (80 meters, 40 meters, 30 meters, 17 meters).  It will be interesting to see if I can make that work.

73 de AB4D. 

New Year's Greetings...2015

Hi.  Just taking a moment to wish those that happen visit my little corner on the web all the best for 2015.  I'm not much for making New Year's resolutions, so none will be made.

I always have a few ham radio related projects on the back burner and future projects on the drawing board.  As I continue to work on various ham radio projects. I will post about them here as they progress.  Last time I checked, there had been over 20,000 page loads of this site over the past few years.  I post not only for myself as a written journal, but also to share the information as well. I thank those of you that may find my writings useful.

73, and have a great 2015.