Long distance ham radio communications via pactor

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I moved from California in 1993 and have been living in Fiji ever since, located on a small island 40 miles from the nearest sizable island having airports, stores, resorts, etc. Because it seems possible that we may be cut off from our usual internet and phone communications systems due to y2k problems, I obtained a Fiji ham operators license and established a ham station here, consisting of a 100 watt transceiver and a half wave vertical antenna located on a hilltop.

I would like to be able to communicate with people in the US (and elsewhere) to obtain news, share information, etc. if other lines of communication are down. Due to the low power of my transmitter and relatively low gain non-directional antenna, voice communication with US stations is usually limited to high power stations with large beam antennas.

The best means of communicating long distances I have found is a digital mode called pactor. There are other digital modes that are also very good, but pactor is the one I am familiar with. Just as Morse code is more readable than voice, this digital mode is also much more readable than voice, and because it is computer driven using sophisticated encoding and error correction methods, it is much faster than Morse. I have a computer and a modem (terminal node controller, or TNC) to interface the computer with the transceiver, and I have been experimenting with pactor. Using 100 watts and a good antenna, I believe I could communicate with another pactor station just about anywhere in the world on the 20 meter band (barring unusual atmospheric disturbances).

Pactor is commonly used in this part of the world by people living on yachts to send and receive email via landbased internet gateway stations. Pactor is a bit more complicated than Morse or voice because it requires a computer, a TNC, and some special software, but once set up it is easy to use.

I am planning to set up a pactor mailbox here where I could receive messages, and I would like to be able to contact other y2k preparation minded individuals via pactor. If there are any such individuals who maintain a pactor mailbox, or have pactor capability, I hope they will drop me a note via email.

I have plans for a power boosting amplifier, and directional high-gain antennas, but due to time and money limitations, I doubt these will be in place by January 1. There is no doubt that lower power methods are better because they require less equipment, less money, and less power.

We obtain our power from diesel generators; we have stored enough diesel for six months of normal operations, and, if necessary, we could stretch it out some. We also have some solar panels that could be pressed into service if necessary.

Best Regards,

Stephen Curtis 3D2SC

Email: Stephen_Curtis@adidam.org (Please note there is an underline character between Stephen and Curtis)

-- Stephen Curtis (Stephen_Curtis@adidam.org), November 04, 1999


Hi Stephen,

You might want to investigate PSK31 mode. It's a chat system, that uses your computer's sound card (and doesn't need the TNC) and SSB mode. I haven't tried it as yet (other preps to do, first), but friends who've used it say you can get longer distances with it. Some of them are using 1 W (yup, 1 Watt) from the US to Europe.

Signals can be so weak that you can't hear them, but PSK31 can pick the signal out of the noise.

A good RTTY system can do the same, but you have to use a good modem (a HAL ST6000) to do it. A TNC can do RTTY, but can't pick the signal out of the noise.

-- Dean -- from (almost) Duh Moines (dtmiller@midiowa.net), November 05, 1999.


Yes, PSK31 sounds like a useful mode. I have a SCS PTC-II TNC, and it can do PSK31, although I haven't tried it yet. PSK31 would be good for a long distance y2k net perhaps.


-- Stephen Curtis (Stephen_Curtis@adidam.org), November 05, 1999.

Could you guys go into more detail about PSK, with details about the right mix of equipment to make it really work? Also about any trade- offs, difficlties, weirdnesses? Thanks in advance.

-- BigDog (BigDog@duffer.com), November 05, 1999.

Hi BD,

PSK31 needs an SSB transceiver and a PC with a SoundBlaster compatible sound card. There's a simple wire between the SoundBlaster in/out and the xcvr's audio out (headphones) and mike connectors.

-- Dean -- from (almost) Duh Moines (dtmiller@midiowa.net), November 06, 1999.

Hello B.D.

From my research, it seems that PSK31 offers keyboard to keyboard chats, similar to RTTY, but with fewer errors, and possible with more interference, weaker signal, etc. It does not allow posting receiving of messages from pactor mailboxes, and it is slower than pactor-2 when transferring pre-typed computer files.

There is a lot of information on the web, including free software. Do a search for PSK31 in http://www.google.com.

Best regards, Stephen

-- Stephen Curtis (Stephen_Curtis@adidam.org), November 06, 1999.

I have also used PSK31, and like it very much. I'd be happy to have a PSK31 QSO with anyone who is interested; just post the suggested time and frequency here or email me with it.

-- Steve Heller (stheller@koyote.com), November 09, 1999.

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