2018 ~ The Year of SSB Transceivers

Why Build Another Transceiver?

10/16/2018 ~ See the latest Video on the Heathkit SSB Transceiver

10/10/2018 ~ Breaking the Guinness Book of Records.

1014/2018 ~ The Heathkit Rig is on the Air

Running 100 MW with just the Driver Stage the Heathkit Rig is doing WSPR. Just installed a Refined Driver Stage with the 2N2219 -- a healthy 100 MW. The Transistor with the heatsink in the lower left corner is the 2N2219

This is the WSPR Data at 100 MW

Get off the couch and start soldering!

73's

Pete N6QW

The SMD board above is the Plessey Bilateral Amplifier in surface mount. This is the work of Nick, G8INE who recently acquired a CNC machine. You can see the small size as compared to the ADE-1 DBM. Nick has done a superb job --and he reports it has been proofed and is a working board!

If you go to my website www.n6qw.com under the Sudden Transceiver link there is a link to G8INE and he has offered to provide the Gerber files for this really small board. Thanks Nick!

Pete N6QW

What are you thinking -- I am not trying to break any world record? My XYL asked me that question today -- why are you building another rig? Followed up by a snide comment that I had so many rigs now why do I need another one. Well the answer plain and simple because I can! 

For the longest time in the late 60's early 70's my success rate with homebrew SSB transceivers was miserable. At that time I lacked the more sophisticated test gear and let's face it some of the technology wasn't that great. Crappy Analog VFO's were high on the list of impediments! I also had to work and to give a fair share of my time to the family -- it is that balance thing.

But today that is all changed --better test gear, better technology like Digital VFO's and a bit more time. The latest project is to demonstrate that some of the components out of boat anchors can indeed be reworked to provide a very modern, very capable rig. I looked through eBay and have seen many crystal filters from heathkit, yaesu, icom, kenwood etc that can be had at very reasonable prices. A good friend just picked up a heathkit filter like the one in my latest rig for less than $15 including shipping.

Previously a big problem was having only the filter did nothing for you without also having the BFO crystals. With the Si5351 -- that no longer is the problem as you can have any BFO frequency between 8 kHz and 220 MHz-- that should cover a lot of filters.

The other factor is that with the currently popular bilateral or as I have demonstrated in the Sudden Transceiver, the single pass with relay switching the total amount of components needed can be had for very little money. Imagine a whole bilateral amplifier strip complete with filter for something in the $20 to $25 range. A digital VFO with BFO and color TFT is another $25 -- a homebrew complete rig for about $100 is a reality. Even less if you have a big junk box. You are only limited by your imagination.

BTW the Digital VFO includes two independent VFO's, USB/LSB select and a tune function. 

Stay tuned for more details on the heathkit SSB rig from the N6QW Laboratories.

73's

Pete N6QW

10/09/2018

The Heathkit 40M SSB Transceiver (N6QW Version) Hears Well!

The N6QW SSB Transceiver Complement:

Receive Section: (Currently working)

• 2 X 2N3904 (Two SMD)
• 2 X 2N3906 (Two SMD)
• 2N3904 Rx RF Amp (Future AG303-86G)
• 2 X ADE-1 (DBM)
• 3.395 MHz Heathkit Surplus Filter
• NE5534 Audio Pre-Amplifier
• LM 380 Final Audio Amp
• Arduino Nano
• Si5351
• 160X128 Color TFT
• Band Pass Filter

Transmit Section: (Under Construction)

• Transmit Pre-Driver, AG303-86G (MMIC)
• Transmit Driver, 2N2219
• Transmit Final, Mitsubishi RDHF RF FET
• Low Pass Filter

This transceiver is on par with the Sudden Transceiver and yes Virginia you can even find some of the circuits in EMRFD. The 2N3904/2N3906 bilateral amplifier circuit (from Plessey) as used in this rig came from there. So it does have street creds for those who think that they will only look at circuits coming from that publication. 

73's

Pete N6QW

10/08/2019 ~ Columbus Day. Chris discovered America (or one of the ones that did) and now you can discover how to use old boat anchor filters in your homebrew SSB Rig!

You can even do WSPR with the new Heathkit Rig. This is receive only using the N6QW Digital Adapter. 

New transceiver  Heathkit 3.395 MHz crystal filter with two Plessey 2N3904/2N3906 bilateral amps. NE5534/LM380 Audio Amp, 2N3904 Mic Amp, 2XJ310 Relay Switched Rx RF/Amp & Tx RF ( a 2N3904 Rx RF for this video). 2N2219 Tx Driver, Mitsubishi RDHF FET for the Final and 2 X ADE-1's for Rx/Tx Mixer and PD/BM/ Arduino Nano, Si5351 and Color TFT.

Some thoughts on switching the BPF's and LPF for 4 Band Operation. On several of my rigs that were multiband and used a common buss for the filters I found bleed through problems and difficulty with drive through the BPF at higher frequencies. With six relays this give 4 bands with either the BPF or LPF and provides better signal isolation over that with a common buss. It will take 12 relays ( @ 60 cents a piece) for four bands and switching both the BPF and LPF. Bottom Line: only one set of BPF's and LPF's connected in line at any one time!

73's
Pete N6QW

2018 ~ The Year of SSB Transceivers

FT8 & WSPR on your Homebrew Rig!

For several months now I have been working on a new SSB rig that will be the subject of a couple of articles in  future issues of the GQRP Club publication SPRAT Magazine.

Run don't walk if you are not already a member of the GQRP Club so by joining you can gain access to the articles. Most of my operation is on SSB but I have come to recognize that many in our ham community have moved over to the digital communications dark side and therefore challenged myself to enable my SSB rig design to "do digital". I am happy to report that I have been successful in running both WSPR and FT8 from the new rig.

All that was needed was the software WSJT-X, a $10 (delivered) sound card interface board, some cables and an old computer with a serial port DB9 connector. That is it. 

With technology advancement comes change. Most new computers do not come with a serial port and thus that presents some difficulties in using the sound card interface device. A tour of Adafruit Industries webpage revealed a product that provides a USB to Serial interface device that has as outputs the DTR or RTS signals (either one) that will key the transmitter. It is a modest price ($15); but opens the door for possible uses with a Raspberry Pi3B or an Asus Tinker Board. WSJT-X  comes in Windows and Linux distributions so there may be a possibility for a very small (and portable) FT8 station. I have ordered one of the units and you can read about it here https://www.adafruit.com/product/284

Here is the interface board kit.

But the real proof is how it works on the air. Below are some screen shots that document the contacts I had. In the WSPR log you will see an entry from VK2ALR when I was spotted 7500 miles away running 5 watts on 40 Meters.

But the most Buzz today is about FT8. So I had to try my hand at that mode and so far have made two contacts. Here is a log of the 2nd contact made this afternoon.

Now I must confess that the FT8 is almost like remote sex. Push a button and the computer takes over and makes the contact. So no long rag chews here. But FT8 levels the playing field using low power and modest antennas.

I am in the process of reworking the sketch for the VFO (it has two). One VFO will boot up normal at 7.2 MHz and the second one I will program to boot up on 7.074 MHz. Thus, flip the VFO select switch and flip the rig to USB and you are on digital!

This is exciting.

73's

Pete N6QW

2018 ~ The Year of SSB Transceivers

Something for the SDR Crowd!

You too can build your own SDR Transceiver!

Second Generation Main Board

The board above is a second generation board and contains the two ADE-1 Detectors and the Modem coupling transformers, the divide by four 74AC74 and to be installed is the band pass filter. If you look close you can see the ferrite core balun used to split the signals going into the two detectors. This is a deliberate attempt at isolating signals and keeping things neat and tidy. I am thinking about a separate enclosure just for this board. Later today I will install the bandpass filter with the intent that it may be used at 9 MHz with a possibility of a different front end. You will have to stay tuned for this.

How about using the SDR on WSPR?

While I can claim I built this rig and added several modifications, by and large the credit goes to Charlie Morris ZL2CTM for his design and software development. You can follow ZL2CTM on YouTube and he has many videos and tutorials!

The bottom line is how your signal sounds AND LOOKS  at the other end. I am really surprised at the number of hams that use either an SDR rig in the shack or use an SDR receiver on the Web for the receiving end of things. Not too many are using a homebrew SDR! Thus it is not unusual to hear that my signal looks really good. To date I have made close to three dozen contacts including a 8000 mile DX QSO with a station in Australia --on 40 Meters. My usual set up is the rig followed by a 100+ watt Solid State Amp kit from CCI and then the Heathkit SB200. Based on my upgrade of the SB200 I typically see in excess of 600 Watts to the antenna. That is a smoking signal!

My 40M antenna is a droopy dipole and that means if I spent a bit more time on the antenna I would hear and work more stations. The center pole is up about 25 feet and the length is 98 feet 3/2 wavelengths on 20 Meters. It is in the shape of an L as it runs along the back end and one of the sides of the lot. The fiberglass support pole is strapped to the tree.

But let us start with the Block Diagram of the basic hardware. Beyond this I have a transmit Driver Stage with a 2N3904 and 2N3866 and the Final amplifier is a IRF510. The relay Switched J310's and the audio amplifier (2N3904 + LM386) are located on the main receiver board. One other item needed to make this play is another bit of hardware from PJRC and that is the sound isolator which I think is nothing more than a modem transformer sealed in a box. The Codec board needs to keep the DC and AC grounds isolated and this is what this device does. In line you hear the amazing SDR signals -- out of the circuit and straight through coupling --garbage!!!!!! It cost $6. One of my modifications was to add modem coupling transformers following the ADE-1's --again the same issue as with the sound isolator. You simply cannot ugly construct this rig and have expectations for success! You will note the date on the block diagram and you will realize this has been a year in the works.

 (R1 is for Simulation Purposes in LT Spice and not used in the final circuit)

The above circuit forms the basis of the driver stage and has been used on many transceiver projects. Ignore the notes and focus on just the 2N3904 and 2N3866 parts of the circuit.

This circuit is used for the Final RF amplifier stage on the SDR. Now a modification to this circuit to accept the Mitsubishi RDHF RF FET would include the replacing the Zener with the 78L05 three terminal regulator and inserting a LED in between the Ground pin of the 78L05 and Ground. which raises the output voltage > 6 VDC. A higher bias level  is needed for the RF FET. Typical output is 6 Watts but higher levels close to 10 watts may be experienced. All other circuit constants remain the same. this is an easy conversion. What is so cool about the LED -- when the circuit is biased "ON" the LED glows --more lights, bells and whistles.

Below are a couple of additional schematic circuits for the SDR Rig with the first being the steerable Dual J310 Amp stage. R3 is for simulation purposes and not used in the final build. R7 is as noted is a 10K trimpot connected as a variable resistor. Note the schematic shows the amp stage amplifying from left to right but the actual install has the amp stage direction going from right to left. I just know someone will install it backwards and then email that it doesn't work. RTM!

The Below sketch shows the modem transformer install.

Now you ask why would you do this when you can buy the IRF510 for about 80 cents and the RDHF is about $5. Well it all depends if you want to operate above 20 Meters. The power output drops off at higher frequencies with the IRF510. So it is all about choice of operating frequency.
Why even the microphone was homebrewed (a first for me). I bought this electret Lavalier style microphone from All Electronics. It is a superb microphone but somewhat costly -- about $1.15 with 15 foot cord. It does not have a PTT switch so I built the PTT using a microswitch I had in the junk box. Starting with a piece of scrap 2X4 about 6 inches long I milled out a cavity so I could mount the microphone and PTT. The remainder of the 2X4 was simply sawed off and ths is what was left. It is palm sized. See below. Aside from some splinters all went well. Not bad for some junk parts a piece of scrap wood and a $1.15 microphone. If you look closely you can see the PTT button sticking out of the case. Not very elegant but it works.

As of 8/11 I have had about 3 dozen contacts including one this morning with a VK station on 40M.

My homebrew Electret  Microphone: (This is one heck of a buy!)

Started like This...

This rig was built based on the design/software from Charlie Morris, ZL2CTM. This is a truly amazing rig as no external computer is required to make it play. While something more than an Arduino Uno R3 is required to make it work,  the Teensy 3.5 and the Audio Codec Board from PJRC will make it stand up tall. This is a $150 class rig but offers many possibilities for use on multiple bands or as I have on the drawing boards a hybrid Crystal Filter/SDR rig.

73's

Pete N6QW

2018 ~ The Year Of SSB Transceivers

7/29/2018 ~ Arduino Code for LCD to OLED replacement http://www.n6qw.com

Look inside the Purple framed text for the link to the code. You will also have to have the included files -- see the notes in the sketch and as mentioned below. If you are unsure on how to do this … don't try it.

73's

Pete N6QW

Secrets Revealed: How to Add a Tune Tone and CW Identifier to your Homebrew Rig. 7/27/2018

Disclaimer: I am not a software programmer nor do I profess to have those skills but I am a person who likes to tinker with things. For several years now I have had a Pulsed Tone TUNE capability with my rigs. I developed the code myself and even figured out how to change the screens to show you are in TUNE. For those who do software on a daily basis --you probably snicker (a lot) at my code. Frankly that is unimportant in that what I developed works!

So today I said to myself "Pete why can't you add a CW identifier following the pulsed tone?" So I did and it works! How this works is that I first put the rig in transmit using the MOX button and then I depress the TUNE momentary push button.

First and all important you need to have a Tone Library in the library section of your main Arduino directory--one that will work with Arduino IDE 1.8.5 -- there is more than one.

There are three lines that must be added initially which state

    #include "Tone.h"
    #define TONE_PIN 6

    #define NOTE_B5  988

Importantly the Tone.h is an included file in the folder and in the sketch that is why it has the quotation marks" ". Next is to identify the output Tone Pin which is Digital Pin 6 and finally Identify the actual tone you want which I chose B5 which is the closest to 1 KHz.

Then we need to identify button states since this is a momentary push button which initiates the Tune process.

   int buttonState = 0;

   int lastButtonState = 0;

We also need to identify the actual Arduino pin that take the Push Button Input to start the Tune Tone process.

  const int SW1 = A2; // provides the TUNE function

Thus we are using Analog Pin A2 to take that input and in the void setup we do that

     pinMode(SW1, INPUT);  // Tune function
     digitalWrite(SW1, HIGH); 

Thus if we put A2 to ground even momentarily it will start the TUNE Sequence.

Now we need to add some subroutines so that instead of writing out the dots and dashes by each element that makes each timed element for a dot space, dash space we can simply call up a dot with all of the proper timing for turning on the tone and turning off the tone. Ditto for the dash whose timing is 3 times as long. So now with the subroutines we can just call up a dash or call up a dot and it will happen automatically. You can even extend this further to writing characters so that you could call up the letters N 6 Q W and it would send those characters. For those who are subscribers to QRP Quarterly you can find a series of article by myself and Ben AI6YR called the CW Sender -- just following our articles! 

Now the delays are set for some slow speed CW which means the newly minted extras who only have to do 5 WPM can read this. Actually it would have been smarter to set up values like: int X = 300; and int Y = 100; and in the delays show it as delay(X); or delay(Y);. This way if you wanted to change the speed you would only need to change two values for X and Y and all else would follow.

//**** Generating CW *********

 void dash(){

       tone(6, NOTE_B5);
        delay(300);
        noTone(6);
        delay(100);
 }

void dot(){

      tone(6, NOTE_B5);
      delay(100);
      noTone(6);
      delay(100);
}

So now we have the dots and dashes and we have the Input pin (A2) and the Output pin ((6) and now for the other subroutine that during the polling of the loop asks have you hit the TUNE button?

void loop() {

       SplashScreen();
       RunOnce = 0;
          
        checkMode(); 

}

So when the loop sees the activation of the Tune Push Button  it shifts to the checkMode() subroutine.

//*********************** See if we are in Tune ***********************************
    void checkMode(){
        buttonState = digitalRead(SW1); // creates a 10 second tuning pulse train 50% duty   cycle and makes TUNE appear on the screen
       if(buttonState != lastButtonState){
        if(buttonState == LOW){
         
        
         
     
          useVFOA(); // Tells what VFO to use for Tune and starts the pulsed tone sequence
        display.setTextColor(WHITE);
        display.setTextSize(2);
        display.setCursor(10,35);   //We are displaying the received Freq of VFO A
               
         display.println(rx1 - bfo);
         display.setCursor(1,50); 
         display.print("TUNE");
        display.display();
        delay(12);
        for(int i = 0; i < 100; i++) {
         tone(6, NOTE_B5);
         delay(50);  // 50 on and 50 off 50% duty cycle
         noTone(6);
         delay(50);
          

         } // This completes the end of the pulsed tone sequence

    

          // The following code sends my call sign at slow speed with a 988 Hz tone. Note

            we are simply calling up dots and dashes. We could take this further to define 

           characters and then this would just say send -- N6QW
          delay(100);   // de N6QW in CW

           dash();   //D
           dot();
           dot();
           delay(300); //E
           dot();

           delay(400);  //A little longer delay between "de" and N6QW

           dash();    //N
           dot();
           delay(300);
           dash();   //6
           dot();
           dot();
           dot();
           dot();
           delay(300);
           dash();  //Q
           dash();
           dot();
           dash();
           delay(300);
           dot();     //W
           dash();
           dash();
           delay(300);
        }
       else{
          //the else resets the screen and puts the rig back into normal operation
        display.setTextSize(2);    // This prints a Black TUNE over the RED TUNE and makes it disappear from the scereen
         display.setTextColor(BLACK);
         display.setCursor(1, 50);
         display.print("TUNE");
   
         noTone(6);
   
       }
         
     
         delay(50);
   
    }
   
   
 That is it and you too can add a CW identifier to your own homebrew rig. Keep on tinkering.!

Pete N6QW

At Times a New Solution > A Fix!

For those not used to mathematical notation the title reads that a new solution at times is greater than fixing the old problem. So it is with a recent experience of mine and I offer this to those who perhaps have had similar problems.

Take the Junk Box Rig which was made (in 2017) almost entirely out of boards lying in my junk box. Often I will build two versions of a circuit module with the first being a prototype and the second the finished unit that benefits from the experimenting with the prototype. Or it may be a case of build the first one large and then the second can be shrunk down in size once the prototype is working satisfactorily. Or as in this case some boards were pulled out of working transceivers as the project was no longer used.

Even though they were junk box boards I did attempt to make it nice looking including a cool blue LCD display. So there you go --Juliyellow background with a blue display. The original Arduino code was a lift from AD7C.

For a long time I had resisted upgrading my Arduino IDE to the latest version because I already knew that the older LCD libraries will not play with the latest IDE's. You can even find some fixes from giants like Adafruit Industries on the internet. Most of my earlier work was done in Arduino 1.0.5 and the LCD Libraries I had loved it.

Well several days ago I wanted to make some changes to this rig and attempted to use the fixed libraries with IDE 1.8.5. Well it will display but not all gets displayed. About 15 minutes worth of frustration was my gag level so I said "Lets rip that LCD out of there and use an OLED"!  The code (not AD7C) was extensively modified by me as used on other N6QW projects.

This has some additional benefits as I recently learned how to make two vfos on the Arduino and I also added some features to the rig that would have otherwise compromised the clean looking front panel. 

So six hours worth of work created new code, milled out a new front sub panel, added some wiring changes/controls  and then final checkout.

The two toggle switches to left of the display are for MOX (for you youngsters MOX = Manually Operated Transmit --you won't find that on your ICOM 7300) and the toggle next to the display selects either VFO A or VFO B. The RED pushbutton engages the TUNE function. When this happen the display reads the transmitted frequency and the word TUNE appears on the screen. 

In normal Transmit (hitting the PTT or the MOX) right below VFO B appears the transmitted frequency. While many of those functions could be done with a 16X2 LCD -- you have a lot more real estate in a small size to display simultaneous information. 

ZL2CTM, Charlie Morris uses a similar display to show a "spectrum" of signals. but you would need something like a Teensy 3.5 versus the Pro-Mini that is being used for this application. I also took this opportunity to make some changes to the Arduino / Si5351 board. 

There are some interesting aspects to this rig. The IF Module uses a 3.180 MHz Crystal  Filter out of an early Yaseu FT-101 and the bilateral amplifiers are the Plessey circuit out of EMRFD. A cousin to this radio a 60M rig has many similar circuits only the Plessey amps are surface mount. The microphone amplifier is a germanium PNP transistor --just wanted to prove I could design PNP microphone amplifier circuits. 

The driver stage is also out of EMRFD but I use a 2N2222 TO-18 (so you can add a heat sink) and a BD139 in lieu of the expensive 2N3866. Works for me. Here is an interesting aside. The driver stage was built new BUT used a blank board that was originally the audio amplifier stage in my KWM4 (NE5534 and LM380). I realized that there was a circuit layout error so simply cut a new board after fixing the error but did Keep the blank board in the junk box. With a bit of juggling that audio amp board became the Driver Board.

The audio amplifier is the healthy NE5534 driving an LM380 (This has the proper board layout). Also an innovation: the bottom plate is a large piece of PC board which has been stiffened with aluminum side rails. There was a reason for this as the bottom plate is the heat sink for the IRF510 that is fitted with an isolating pad and simply screwed to the bottom plate. Copper is better as a heat spreader and you can verify that with your friendly EMRFD or uBitx illuminati.

Oh, the Band Pass Filter was originally used in the LBS transceiver project. So almost like a wedding something old (old boards), something new (new driver stage built on an old board), something borrowed (LBS BPF), something blue (the PNP audio transistor and the original LCD).

So a problem has turned into a better solution with greater capability. Throw out those LCD's and get an OLED or really go uptown with the Color TFT. For those who wonder --there is no OLED noise in the receiver! I am getting to believe OLED noise is like the phase noise of the Si5351 that was touted before it became an old wives tale.

Oh, not done yet --the sub-panel will be painted black today. That should make the OLED sort of disappear into the background. Done --- See below.

Pete N6QW

2018 ~ The Year of SSB Transceivers

7/10/2018 

7/1/2018

6/21/2018 ~ 6 and/or 4 Meters Your Band?

Yes you are reading that the displays are saying 6 meters or 4 Meters. There are many possibilities with the Arduino and Si5351. These are but just a couple examples. No, the 6 or 4 Meter hardware is not built but if you have such rigs and need a sketch email me n6qwham@gmail.com

6/18/2018 ~ More Possibilities

The code has been ported over to the Color Touch Screen and the 160X128 Color TFT. Lots of possibilities!

Pete N6QW

6/17/2018 ~ New and Improved Code

(Up on the link)

No Flickering of the Display !~ Thanks DuWayne KV4QB!

6/16/2018 ~ Two VFO Code: 160X128 TFT

http://www.n6qw.com

Follow the link and look for the Simpleceiver project. There you will find a link to the code where the code is a notepad document. Copy and paste into an Arduino sketch. Note below:

• The sketch is made with Arduino IDE 1.8.5
• The display is a 160 X 128 Color TFT
• You must have all of the libraries in your Arduino directory for this to work
• You must also have the "included files" in the project folder for the sketch to include Rotary.h, Rotary.cpp, si5351.h and si5351.cpp. You can find these files under the Bitx40 link (on the website)  and these too are in notepad form.
• This is provided for you as a roadmap of what I did. Quite honestly --it works for me but I am not an Arduino expert --simply a Radio Genius. 
• Do not take me to task for not having elegant code -- I will leave that to you EMRFD and uBitx illuminati. But what is shown is a workable two VFO rig. If I knew what I was doing the code task would have been a lot easier -- but the bottom line I have it working on three different types of displays. By and large the Touch Screen was the easiest to implement 
• Opening the connection that is made to Pin D4 (with another 1N4148 in line with the wiring with the Cathode connected to the PTT connection) will provide a functionality of independently transmitting/receiving on either VFO A or VFO B. So now the options are 1) Transmitting/Receiving on VFO A, 2) Transmitting/Receiving on VFO A but independent receive on VFO B and 3) Independent Transmitting/Receiving on either VFO A or VFO B. However some of the display status info would not be available with option 3 -- but the rig will operate normally. I may internally mount a switch inside the box so I could engage option 3.
• You will need one external relay connected in series with the switch that selects VFO A or VFO B. This relay is opened during transmit so that while you can receive on either A or B you will transmit on VFO A. The relay coil is energized off of Pin D7. The relay is a 5 VDC unit with a 178 Ohm coil --doing the math (E = IR) that means the current draw is 28 Ma. The max current draw form an Arduino pin is 40 Ma.
• I received a "concern inquiry" as to the relay coil connected directly to an Arduino pin. While I did not previously mention this, I have a 1N4148 "Snubber Diode" connected across the relay coil with the cathode connected to the Arduino Pin.  (Pin D7)

73's
Pete N6QW

6/15/2018 More on the Color TFT Displays

Part II of the New Dual VFO Simpleceiver.

The Paint Over is Resolved!

73's

Pete N6QW