Monday, October 16, 2006


Back in the good old bad old days of 1979 I caught the RTTY bug. In those days my first machine was a Creed 7E which was a veritable boat anchor of the teleprinter world.

Returning to RTTY or MMTTY which I now use seems a world away.

My first challenge (After lugging aforementioned 7E up two flights of stairs) was to build/buy a terminal unit. In those day the easiest way to achieve this was to buy the BARTG ST5 Boards. A couple of 88Mh post office toroids and a few MJE340s later and voila, away you went.

Of course it wasn’t that easy. For some obscure reason UK hams worked AFSK with a 1275 and 1445Hz tones, Why? I guess it was an historic thing but this was bad news if you were trying to run FSK through an SSB rig (The 2nd harmonic was right slap bang in the audio pass band). Also all the Japanese rigs with HF were set up for high tones (i.e. the tones we use as standard today). Some time between my going QRT and reactivating the world saw sense and high tones rule (Well I only run pure FSK so they do for me).

Another problem was the motor running the 7E which was DC governed. This was good and bad.
Good as the machine was set up for 50 baud and was easily adjusted down to 45.45, and bad as it had more in common with a Marconi spark gap transmitter than a teleprinter. I tried everything to silence the beast but relief only came in the form of the Creed 444.

Technology was moving apace and these machines were just becoming available on the market. With a pair of BARTG gears to get it down to 45.45baud I at last had a quiet machine. Okay it was even heavier than the 7B but in its day was the best you could get.

If you were wondering I was a member of the local radio club EADARS (G3UUP) which did a lot of RTTY contesting in the 70s so I had no problems finding help or learning the RTTY ropes. I also learned that I was not built for 24hr contesting. At about 3am on the keyboard my body would realise it wasn’t going to bed and would start to scream for sleep. But it was a blast. We had a nice ST6 a reasonable linear, a TH6DXX and with the sunspot cycle at max could work the world.

I think the very difficulties RTTY presented in those days generated a sort of camaraderie amongst the RTTY orientated Ham community. Anyone could bung up an aerial and plug in a rig and holler CQ but it wasn’t so easy to get RTTY up and running in those days (Then try running the WAE QTC contest with punch tapes! definitely a multi-op multi-machine affair!).

Of course personal computers were the next step and slowly we observed the steady increase (through observation of the increasing black mark on the right of the print roll -No CR LF) of computer based RTTY.

When I came back to radio I discovered MMTTY.

Of course I am an old dog and MMTTY was a bit of a new trick. But I had a PC and compared with all the problems with terminal units and teleprinters MMTTY is a breeze. Better still the FT-107 is set up for proper * FSK so connections couldn’t be easier.

Actually I cheated and bought a MicroHam interface, but there is no serial port on my pc so it was the easiest option.

I now have a nice tight 300Hz CW filter fitted in the FT-107m (Courtesy of Carol W4CLM and Fox Tango). After 25 years the 107 needed a bit of realignment (that’s a whole ‘nuther story) but less than me. For now there’s nothing more pleasant than a few hours working the HF RTTY contests during the weekends.

Only thing is 100w + on 80 or 40m and my internet connection dies, something I have yet to sort.


Please do not adjust your set! Maybe its just a few lids out there but I spent a long time aligning my RX to TX frequency. Its good to about 10Hz! I find there is nothing more annoying than to reply to a station who is call CQ who then comes back at a different frequency? If you must run AFSK or cant align your TX frequency and or shift please switch off the wretched ATC button on MMTY. By all means use the RIT but remember it’s a Receiver Incremental Tuning control not a TIT!

** FSK is obtained in the FT-107 and FT-902 etc by creating a carrier and shifting it by 170Hz not by using SSB and tones.


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