BITX40: A Fully Assembled $45 SSB QRP transceiver

bitx40v3_main

Many thanks to Pete (WB9FLW) who writes:

Don’t know if you have seen this or not. VU2ESE of BITX20 Fame has just introduced the BITX40.

This is a fully assembled and tested SSB Transceiver for $45 including shipping from India!

http://www.hfsigs.com/

Wow! I may have to purchase one of these and try it out.

I’m currently teaching a HamRadio 101 course to a group of 13 year olds. One of them recently asked how much it would cost to get a basic HF radio kit with SSB mode.  HF rigs–even basic ones–tend to be quite expensive if they include SSB.

Here are details from the BitX40 order page:

BITX40
Work the world on 40 meters

When was the last time you used a radio you had built? The BITX40 board is single circuit board 40 meter SSB transceiver module. Inside an evening, you can be on-air with this SSB transceiver module, chatting with the local gang or chasing DX. Plug in the earphones, the included electret mic, tuning and volume controls and you are on air! Included are high quality connectors, all the needed sockets and jacks, tuning and volume controls, mounting hardware, etc.

Technicals

The BITX40 is a very clean, crisp and quite receiver. The front-end has a triple tuned circuit that cuts out-of-band signals from getting inside, a diode ring mixer front-end with a very low phase noise, all analog oscillator makes this a crisp receiver that doesn’t overload easily. The all analog signal path to your ear makes provides outstanding signal clarity that is to be heard to be believed.

7 watts of SSB provides you with enough juice to have thousands of contacts on 40 meters, daily rag chew and occasional DX chasing. Any common 2 ampere 12 linear volts supply will provide enough juice for this transceiver. Or you could simply run it from a battery!

Hackable

The BITX40 will inspire you to experiment. Modify it, mount it, tweak it, change it.

The PCB uses all analog large sized SMD components that are laid out on an easy to understand manner on a double sided board with broad tracks. This can be your main module around which you can start experimenting. There are jump-points from where you can add more modules like the DDS, more bands, better audio amplifier, etc. Imagination is your limit. You can separately increase the power amplifier’s supply voltage to 25 volts to be more than 20 watts of power : You will have to add a better heat sink. The mods are on the way!

The board can be installed inside any box that you like. Make your own station rigs, man-packs, trail radios or mount it in a cigar box and leave it on your bedside table. The tuning capacitor has been replaced by a varactor tuning so you can place the tuning knob anywhere as it only carries a DC voltage. Watch the instructions video.

Box Contents

We have tried to include connector/hardware you might possibly need to build a full radio. However, we also had to balance the shipping weight to keep the overall cost down. You will have to supply your own box, power supply and earphones/headphones/speaker.

  • 4-1/2 inches by 5 inches tested SSB transceiver module, covering any 150 KHz segment of the 7 MHz band
  • Small electret microphone
  • High quality BNC connector for the antenna
  • Two earphone style audio jacks for the mic and the earphones/speaker
  • A set of DC power socket and plug
  • Volume control with on/off switch
  • 100k linear pot for tuning
  • 4 Brass stand-offs with mounting nuts and bolts
  • Connectors with wires for all connections on the board

* Note : A speaker is not included in the kit as earphones/headphones/speakers are easily available locally. No cabinet is included to save on the postage cost. Almost any box maybe used.

Manufacture

The BITX boards are hand assembled by a collective of women. Each of the toroids is hand wound. This provides these women with livelihood. The assembled boards are then DC checked a final RF check is performed to check the receiver’s sensitivity as well as transmitter’s output before being shipped. Each board is individually numbered.

Click here to view the BITX40 ordering page. 

24 thoughts on “BITX40: A Fully Assembled $45 SSB QRP transceiver

  1. Ron

    Hi,
    I may well order this to use as a basic fun rig when out camping. seems there is not a lot to add to get on the air.
    73s.
    Ron

    Reply
      1. Leonard Fernando

        Dear Thomas,
        After reading the BITX40, I was impressed! It’s a very valuable project for QRP operator, as well as a starting equipment for young Ham who is dreaming to go on the air! With an affordable price! On the other hand the constructor or the founder of this I congratulate for the achevment!
        Also Not forgetting the livelihood for the ladies who has some thing to do, and it’s too is a collections of merits!

        Kindest Regards and Best of 73!
        Leonard Fernando.
        4S7LF / OZ6ZV.

        Reply
  2. Dan...VR2HF

    The obvious glaring omission is no CW transmit capability. Anyone know of a mod to add it? At this point in the solar cycle an SSB only QRP transceiver is really not an attractive buy at any price.

    Reply
    1. Thomas Post author

      I think the unique thing about the BITX40, though is that it is an SSB transceiver. There are some modestly priced CW transceiver kits out there, but none with SSB. One you might check out is the CW only QRP Pixie: http://ebay.to/2emPEJf They range in price from $4-6 US shipped!

      It’s true that with a miserable solar cycle, SSB QRP is more of a challenge, but it’s still worth it.

      Yesterday, I did a National Parks on the Air activation with my KX2 QRP in SSB mode on the Blue Ridge Parkway. In 30 minutes, I worked 26 stations in California, Washington, Montana, New Mexico, Texas, Kansas, Nebraska, Mississippi, Rhode Island, Vermont, New York, Florida, Spain, Belgium and a guy 6 miles away in North Carolina. 🙂

      I believe QRP is still worth it! 🙂

      73,
      Thomas

      Reply
      1. Dan...VR2HF

        Good points, Thomas. My point is that for a couple more dollars they could add CW TX capability and make the BTX40 a much more usable and desirable radio, and increase their sales too. There is simply no way I am going to buy an SSB only transceiver (unless it was as a dedicated JT65A transceiver as Mike suggests). I hope they are listening over there in India!

        Reply
        1. Thomas Post author

          I agree, Dan…that would be mighty cool! I especially like the idea of a dedicated JT65A transceiver. That’s a mode I’ve yet to try.

          Reply
          1. Michael Black

            No.

            A pure audio tone into the microphone jack will result in CW, if the transmitter has sufficient carrier and opposite sideband suppression. Some rigs did it in the past, like the Collins KWM-2, though I gather it used too high a tone, causing other problems.

            So long as it’s a pure single tone, the SSB transmitter just translates it up to RF, so it’s the same as a CW signal generated any other way. But since it’s an audio tone, the output signal will be offset from the suppressed carrier frequency by that audio tone’s frequency.

            But if you just feed the tone through a microphone, whatever else the microphone picks up will be transmitted. So people speaking, the tv in the other room, a noisy fan, bumping the operating desk, all of that will go out, generating an AM signal, but with one sideband suppressed.

            Michael

    2. Bob — KK5R

      Why not a good audio oscillator piped into the SSB Microphone jack? It would produce a good CW signal. The price of this would also make it attractive. It would need to be a nice sine wave, nothing harsh or “buzzing.”

      Reply
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  4. Dennis Cornell N7HRO

    If you want a cw qrp the LNR LD-5 is a great little 5 band and does both CW and SSB. I found one for $500 used. They run about $580 new. I am looking forward to finding an enclosure for this little rig. It will be a nice addition to my shack and the camper when we get on the road.

    Reply
    1. James Johnson

      Why not use a Alinco DX-SR8T on low power? It is all bands and I have seen it selling new for about 480$ US. Maybe if you have the money you could consider a Yaesu FT-891 for 579$ US. These radios have low power capability, I believe, and they cover MF and HF.

      James
      AJ5AE

      Reply
  5. Bob Kreig

    Hi nice kit indeed! The frequency reader is not mentioned. I imagine with a small LCD display. Can you confirm? Thanks. Bob I1ARZ

    Reply

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