The FT-857D: My most versatile and least-used rig

I’ve owned an FT-857D for about six years now. I bought it for the same reason that I can’t bring myself to sell it – its diversity:

DC to daylight, a gazillion modes and all that…CW, V/UHF repeaters, satellite work, mobile operation, etc. Heavy on the etcetera.

The FM “easy-sats” were fun for a few days, APRS for a couple weeks and 2m FM for a few milliseconds.

Now there’s a new use for the ’857. An article in July’s QST talks about a way of converting the it (and other rigs) to a “psuedo SDR” radio. If the article were complete, it would be many pages long – but it did entice me to visit the relevant web page and join the Yahoo group to learn more about this possibility.

In a nutshell, the article is based on a small circuit (offered as an inexpensive kit) that plugs into a spare crystal filter socket, extracts the 2nd IF, converts it to 12 kHz, feeds it into a computer and, with dedicated software, presents a pan display and demodulates the signal rather than having the rig downstream of the IF do it.

No separate I and Q data as we’ve come to expect from true SDR – just the basic IF being demodulated and displayed. Doesn’t float my boat.

So what to do with the FT-857D?

I think its latest employ will be as a dedicated 6m rig. I’ve become more interested in that band lately and would like to explore it in some manner.

WSPR doesn’t seem too common on 6m – CW beacons seem to be the indicator of choice for propagation info.

The is a coordinator for 10m beacons (WJ5O) but, despite my best efforts with Google, I can’t find one for 6 meters so I guess folks do their own research of who’s on what freq & where they are geographically and go from there.

Another option is something involving Radio-SkyPipe which is also mentioned in July’s QST. Commonly used for observing Jupiter’s transit via signal strength on 20 MHz, I ran the program starting an hour before sunrise yesterday and was able to mark the time of sunrise on 25 MHz in the same manner. Other solar observations via SkyPipe are here (they need to adjust their clock to get DST to agree with GMT).

The FT-857D is a diverse rig with many possibilities – jack of all trades, master of none.

Now what to do with it…

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  6 comments for “The FT-857D: My most versatile and least-used rig

  1. June 14, 2012 at 2:55 pm

    Well, if you really don’t know what to do with it you can always donate it to me ;-) Just kiddin’. Doesn’t the radio get hot with only 15 secs between transmissions as a beacon. I use a Icom IC-706 which is I think comparable with this Yaesu, the Icom has a habit of getting hot even at lowest power. 73, Bas

    • June 14, 2012 at 3:01 pm

      Maybe I’ll do that, Bas…just kidding! It’s only about 15F above ambient but I wish there was a way to turn the fan on 100% of the time. As it is, it kicks on at the beginning of each transmission.

  2. June 14, 2012 at 5:53 pm

    You should really try the MDSR – LIF on the FT-857. It is simple and effective. The IC-7600 has a single ended DSP and it is hailed as one of the best rigs currently on the market. Additionally you get a real time spectrum display which is only offered in high end transceivers. Can’t beat this for $25 for the kit.

    • June 14, 2012 at 6:28 pm

      Alex, I may try it yet just to satisfy my curiosity and the urge to tinker.

  3. June 14, 2012 at 7:33 pm

    Yesterday I asked Alex a few questions regarding the MDSR-LIF. Here is his answer, posted here with permission:

    “The FT-857 is the perfect radio to use with the MDSR and LIF setup. Single ended
    signal IF processing can be very effective as proven in the IC-7600. Our
    objective was to provide excellent performance without the complexity as well as
    a spectrum analyzer that will display +/-10kHz of the IF spectrum. Further more
    the I/Q approach requires a lot more processing power. The MDSR software can
    work perfectly on your existing computer and you can browse the internet while
    you are listening to the demodulated RF.

    To do I/Q signals is complex and it is totally dependent on a perfect 90deg
    offset. This not only requires a dual 90deg locked oscillator, but also a
    perfectly matched dual RX line. The advantage of the I/Q approach is that the
    full bandwidth to the ADC can be used. Since we are using an existing
    transceiver with a bandwidth of about +/-10kHz and the soundcard native
    bandwidth is already 22kHz this technique is not required.

    The real advantage of the MDSR demodulation compared to the FT-857 demodulation
    system is the fact that the IF is digitized and then filtered before
    demodulation. To provide signal processing after the IF noise had been scrambled
    into the AF is a futile undertaking.

    Since the IF filtering is done digitally, the IMD performance and the mixer
    noise are improved. Additionally the co-channel interference can be eliminated
    because of the steep digital IF filters. Sensitivity is improved because the IF
    filter bandwidth limits the unwanted signal (noise) to be processed by the
    demodulator which raises the S/N ratio.

    In short the MDSR provides improved audio quality and a spectrum analyzer for a
    rock bottom investment if you buy the kit. Also make sure that you get the LIF
    into FT-857& 897 pdf document from the Yahoo user group. It describes the LIF
    installation procedure in detail.

    All the best,

    Alex
    VE7DXW”

  4. June 15, 2012 at 7:38 am

    For those who aren’t members of the associated YahooGroup, here is the supplement to this month’s QST article on the MDSR-LIF kit (1.4MB pdf):
    http://www.ae5x.com/docs/MDSR_indepthArticle.pdf

    I’m not endorsing it, just passing along info.

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