The Annual General Meeting of the Portland Amateur Radio Club will be held at 1930 on the 11^th May 2006 at the Clifton Hotel Portland. All members are urged to attend even if it’s just to enable us to put a name to a face or a voice!

All attendees will be welcome to join the regulars in the pub quiz after the meeting; we need to win a bottle of wine or two for the next club "get together"!

Not much from me this time, but please make every attempt to attend the AGM. All positions on the committee are up for grabs, but there will be no pressure on anyone to fill any posts. This will be a chance to pay subs to the treasurer [‘Nelsons’, or ‘Chang Kais’ made out to PARC, please], have your say on what you’d like done this year, what we are doing wrong, or right etc.

Formality will be kept to a minimum and non-members/prospective members will be welcome although they cannot vote.

Just a reminder to SWLs / scanners, as well as licensees. The club nets are at 1900L Sundays and Thursdays on 145.575 with a listening watch on 10120khz CW. RSGB news is read at 1100L on Sundays on 145.525 Mhz with a reserve slot at 1900L if it is not possible to transmit in the FN.

On Thursdays at about 2030L members are in The Clifton Hotel in Grove Road Portland to put a face to a call sign or field any questions. Please join us and particularly at the AGM where you will be welcomed.

Well, the use of stripboard has now entered the 21^st Century with the availability of computer aided design (CAD) tools to assist us with its application!

Specifically, I am referring to a piece of (free!) software called VCAD (for ‘Veroboard CAD’!), available from http://www.geocities.com/rogerlasau/VCad.html

Put simply, VCAD allows you to lay out a stripboard circuit on your computer screen, before ever committing it to actual hardware.

Initially, you are presented with an image of a piece of blank stripboard of variable size. Onto this can be placed pins, for wired connections to the circuit, wire links between rows of copper. Also, breaks can be made in the strips, as one would do when laying out a real stripboard circuit.

When it comes to placing actual components we can define their outlines in terms of either two pin parts such as resistors, diodes and so on, or multi pin parts such as integrated circuits.

These parts can then be placed on the screen layout and positioned as desired. Finished layouts can be printed and used to build the final circuit, using real components!

Now, even so far, the program is useful, but the real power of VCAD is in its ‘netlisting’ capabilities.

Netlisting is a capability of ‘proper’ CAD software used for tasks such as printed circuit design. Essentially, a netlist defines a circuit diagram in written terms. It would contain a list of components used, their characteristics, and a set of nets outlining connections between the components. For example:

……is a small section of a real netlist and tells us that there exists a connection - or ‘net’ (called N000000), between terminal 1 of diode D3, terminal 2 of diode D5, and terminal 3 of integrated circuit U3, and another (N000001) between pin 1 of D2, pin 2 of D6 and pin 13 of U2. I hope you can see that any circuit diagram can be described by a netlist of appropriate complexity.

A netlist is typically used to assist in the conversion between a circuit diagram and a PCB design, and can be used to confirm that the two match.

VCAD has very similar capabilities, and we can import a netlist produced from a CAD circuit diagram, and use it to assist with our stripboard design.

Having assigned our list of components to actual physical outlines, we can place them on our stripboard layout accordingly, stretching some of them if necessary to fit across varying numbers of rows of copper strips.

By invoking a command in VCAD, our layout is checked against the netlist and any problems, such as component pins in the wrong place, or component pins not connected to their corresponding nets, will be highlighted - a very handy facility.

Shown below is an example of a VCAD design that I produced. In fact, it is the design for the experimental Huff and Puff VFO that I am currently working on. Clearly visible I hope are the components, straight wire links, pins and track cuts (‘X’ shapes).

One small limitation, as can perhaps be seen in the above example, is that the symbol editor is somewhat limited at the moment in the variety of component shapes it can produce. The author of the software has expressed the desire to improve this side of things in future, and in any case this is not a serious limitation to actually using the software.

Whilst many CAD software packages produce netlists suitable for use with VCAD, if you do not have one of these (and I didn’t), there is another freeware CAD package that can be used with VCAD – this is called TinyCAD, and I can again vouch for its usefulness, having also used it for the VFO project. TinyCAD is available from: http://tinycad.sourceforge.net/

This organisation was formed by the Rev. George Dobbs, G3RJV, back in 1974 to cater for those interested in low power communications.

The Rev. Dobbs is perhaps more familiar to us all as the person behind the ‘Technical Topics’ section of RadCom (some would say, the only part of RadCom worth reading these days, ho hum!).

My interest in the group was aroused as a result of my ongoing BITX20 project, which squarely falls within the QRP category with about 7W output on phone (QRP power levels are considered these days to be a maximum of five watts output for CW, or 10W PEP for SSB).

Anyway, I decided to join at the beginning of January, for the princely sum of £8 p.a. The club has a quarterly magazine called ‘SPRAT’ (for ‘Small Powered Radio Amateur Transmissions’). SPRAT is a small but interesting magazine, crammed with technical, operational and constructional articles. Refreshingly, there is a minimum of adverts.

More information about the G-QRP club can be found on their web site at http://www.gqrp.com

Geoff Birch (G0GWY) offers the following items for sale:–

• YAESU FT-707 HF SSB Transceiver
• YAESU FC-700 Antenna Tuner
• YAESU FP-707 Power Supply £225.00 ono
• ICOM IC-290 144MHz all mode Transceiver £130.00 ono
• ICOM IC32E Hand Held FM Dual Band Transceiver £ 90.00 ono

Contact him on: 01305 821968 or 07990937285

Rod (2E0CTS) has the following piece of kit for sale:

• MFJ-784B Tuneable DSP Filter. Cost £159.95. (Bought to go
  with a Realistic DX394 but the set works well without it.) £100.00 ovno

Contact him on:- 01305 820893 (home) or 01305 838432 (work).

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