Shortwave

At begin of 2008 I was on a business trip in the US and couldn't withstand to buy a [external link] Yaesu FT-817ND for an extremely good exchange rate. And I don't regret it!
Although I only was active on VHF/UHFVery / Ultra High Frequency, all frequencies above 30 MHz until that time now I have a lot of fun also on the shortwave bands in spite of or just because of QRP powermax. 5 Watts!

My transceiverTRANSmitter + reCEIVER in one rig: Yaesu FT-817ND

My FT-817ND

I think almost every radio amateur knows this little rig or at least has heard of it. For those of you who don't here are the main facts:

You can find more details in the [external link] RigPix database.

The most important advantage to me is that this is a all-in-one rig which can easily be used portable.

Antennas

Together with the FT-817 I bought an antenna for portable use: the [external link] MFJ-1899T.

MFJ-1899T antenna
The MFJ-1899T antenna
left: ready for operation
right: ready for transport
(the PL ellbow adapter and the BNC-PL-adapter were not included in delivery of the MFJ-1899T, I use them to connect the antenna at the rear antenna port (PL) instead of the front port (BNC))

It can be used on all HFHigh Frequency = shortwave bands up to 30 MHz bands and 6 meters50 MHz band. It consists of a loading coil which can be bypassed with a "wander lead" in several stepps for getting resonance on the different bands and a telescopic whip which allows fine tuning. With its BNC connector it can be plugged directly to the front antenna outlet of the FT-817.
Its operation requires a counterpoise with frequency dependant length.
The connection to the BNC is a little instable. I wouldn't trust it in heavy-duty portable jobs.
Up to now I used this antenna only for receiving as long I haven't had a better antenna. Hence I don't know how it works when it is used for transmission.

In November 2008 I bought a used magnetic loop antenna with a diameter of 80 cm which can be used from 40 to 10 meters7 to 30 MHz.

My magnetic loop antenna (ML-80)
This is my magnetic loop antenna ML-80 from Hilcock Projects lying on my balcony with open box with the motorised variable capacitor and w/o the motor control cable

I installed it as a stealth antenna among some trees in the garden. At the beginning I was a little sceptical about the performance. The efficency of magnetic loops decreases with the diameter / wavelength ratio. For 20 meters14 MHz and above it does a good job but on 407 MHz and 3010 MHz meters? With only 5 Watts output and a 25 m long cable between transceiver and antenna?
But I was pleasantly surprised! Okay it is really no DXlong distance antenna, but inside Europe it makes a great job. It is not always easy to get reply from CQ calling stations but all the more is feeling of success if they do!

After I had to remove this antenna now I use a [internal link] 17.2m long end-fed random wire.

PSK31

But how is this possible? Up to now I didn't mention which modes I use! Unfortunately I forgot almost all my CW knowledge I learned about 25 years ago for my license exam because I never practiced it on the bands. But why meanwhile the PC became cheap and popular? Therefore I mainly use narrow band digital modes, especially PSK31.
In priciple you can also decode and code CW with a PC. But I think that's like a sacrilege to all the excellent CW operators when I come along with my computer generated signal...

PSK31 is a modulation based on Phase Shift Keying with a transmission rate of 31 Baudcharacters per second. That's where its name comes from. You will find more detailed information in [external link] Wikipedia. Due to its very low bandwidth of about 31 Hz this mode has a very high signal-to-noise ratio. Thus it is predestinated for QRPlow power operation. The transmission rate of 31 Baud was choosen because this value results approximately from the the keying speed of 50 words per minute of a normal computer keyboard user. Hence no higher bandwidth is required for a fluent communication.
Besides PSK31 there are PSK63 and PSK125 which allow a higher transmission rate. But due to the higher resulting bandwidth the signal-to-noise ratio is worse compared to PSK31. These modes are often used in contests where the comminaction can be standarised with macros generated by the used software.

Today the most common way is to generate the PSK31 signals with a soundcard of a computer (PC). Also the received signal is fead to the soundcard (mic or line-in plug). All soundcards can be used for these purposes. The coding and decoding is performed by software.

Software for PSK31 (and other digital modes)

I use [external link] Digital Master 780 (DM780) for the digital modes. This program is part of [external link] Ham Radio Deluxe (HRD), a freeware amateur radio software suite which additionally includes programs for digital logbook, satelite tracking, rotor control etc. It was written by [external link] Simon Brown, HB9DRV.

I choose it firstly because it is freeware, secondly because I already used the [external link] FT-817 commander (also from Simon) for controlling and programming my FT-817 and last but not least because it is an European product ;-)

[click to enlarge]
A screen shot of DM780

I am very satisfied with this software. I like its user interface and that it is an all-in-one solution for operating, logging and more. But I don't have too much comparision. I only tried some other programs for a very short time. I am sure that each has its own advantages and disadvantages.
The only disadvantage of HRD I recognised up to now: maybe it is not the best solution for constesting. A lot of functions need mouse control and that's not the most ergonomic way of controlling software.

Interface between transceiverTRANSmitter + reCEIVER in one rig and PC

As mentioned above the PSK31 signals are generated and decoded by the soundcard a of a computer. That means you have to connect the soundcard to the transceiver. Additionally the software must be able to trigger the transceiver to transmitting mode. That's why some cabeling and interface is required.

In order to avoid ground loops both items shall be connected with galvanic isolation. For the analogue signals the simpliest solution are isolating transformers.
For the digital PTTPush To Talk = transmission signal opto-couplers can be used. Most digital modes programs use the RTS signal of the COMserial interfaces for controlling the PTT. DM780 can also control it via the CAT interface if the transceiver has one (like the FT-817). Besides PTT the CAT interface allows to control other tranceiver parameters (like frequency, output power etc.).
On [external link] Ernie's (WM2U) homepage you can find a lot of information about interfacing including suggestions for simple or more sophisticated interfaces, information about hook-up points of the connectors at different radios etc. etc.
Modern PCs often don't have serial interfaces anymore. In these cases you can use a USB to COM adaptor. There are also interfaces available with build-in soundcard which require only a USB connection on the computer's side for the signals and PTT control.

I use an interface made by [external link] M0AQC and am very satisfied with it ([external link] see other reviews at eHam.net)! It is one of the kind with isolating transformers and opto-couplers.

Digital modes interface by M0AQC
Digital modes interface, open

PSK31/p
or
How can I use PSK31 also for portable operations?

This is still an open topic for me. In principle there are three ways for digimode portable operations:

  1. with a notebook or netbook and standard digimode software
  2. with a PDA or mobile phone with Windows Mobile and the [external link] PocketDigi software by OK1IAK
  3. with a special device, like the [external link] NUE-PSK Digital Modem or the AATiS PSK-Controller*, which requires no computer (only a keyboard)!
    *) I found only one link in German: [external link] DARC Forchheim (B26) [in German language]

In cases 1 and 2 you need an interface between transceiver and the used computer.
In case 3 you connect the digital modem directly to the transceiver. The big advantage for portable operations: you need no computer (less weight and space)!

Let me short explain why I am interested in using PSK31 also at portable operations. In May 2009 I spent my holidays on Lanzarote Island (Canary Islands, IOTAIslands On The Air AF-004). This was the first time I took my radio (+ a portable dipolesimple antenna made of two wires + tunermatches the antenna electrically to the transmitter/receiver) with me. I heard a lot stations from Europe, America and Africa. But nobody heard me! Really not one QSOcontact over radio during 2 weeks of holidays! Neither my replies to CQ calls were answered nor calling CQ by myself was successful. (I mainly tried it on 20 meters14 MHz band].) That was extremely frustrating!

I asked myself why could this happen and found some factors:

I think the first two points are the most important ones. The antenna worked fine during my first [internal link] SOTA activation on shortwave (OK, I know: 40 meters is a different band!) and I checked it with my antenna analyzer. QRP and SSB is not a good combination! I knew this before but I didn't think that it can be that problematic!

Hence I decided to try PSK31 in my next holidays! But I didn't decide yet which of the three possibilities I will use. Maybe the cheapest solution is a PDA and PocketDigi. Let's see!
Update: Meanwhile I bought me an MDAPDA/PocketPC with integrated mobile phone and got some experience with it, which you can [internal link] read here [in German language], if you understand German.

 

Weblinks

FT-817

[external link] HF/RF - Clipper Speech Processor by DF4ZS [in German language]/[in English language]
Not a simple dynamic compressor!

[external link] K6XX's FT-817 pages
with a simplified user's manual, interesting diagrams: current drain and  supply volatge versus output power etc.

[external link] KA7OEI's FT-817 pages
with a lot of tips

[external link] Yaesu FT-817 Links by K8ZT

PSK31

[external link] NUE PSK Modem
for PSK with out PC!

[external link] PSK Meter by KF6VSG
allowes to check your modulation

[external link] PSK tutorial of the QRP Radio Club

[external link] Soundcard and interfacing schemes by WM2U

Software

[external link] DigiPan

[external link] DM 780 (part of Ham Radio Deluxe)

[external link] MixW

[external link] MultiPSK

[external link] PocketDigi
PSK, RTTY with a PDA/MDA with Windows Mobile