Welcome to the fifth issue of WyrePak Newsletter - I hope you will again find something to interest you and while away a few moments! Many thanks to those kind members who said they enjoyed the last issue too.
Whilst browsing through the Winter 2001/2002 edition of the WyrePak Newsletter recently, I came across the article about old computer memory, and the 1k core stores constructed by hand from tiny ferrite beads... readers may be interested to know that there is one of these actual items on display in the Computing exhibition in the Science Museum in London. It must be said, however, that the computing exhibition itself is something of a museum piece, as it does not appear to have been updated since the early 1970s, and the ferrite bead core store is presented as state of the art technology! During my visit to the Museum last March, I found several exhibits in this sort of time warp, including the amateur radio display which featured just a couple of 1970s transceivers (with red LED displays!) Still, I suppose it is a museum.
Meeting dates for your diary (all Tuesdays) are: 20th August, 17th September (AGM), 15th October, 19th November, 17th December.
Can I take this opportunity formally to advise all members that the group's Annual General Meeting will take place on Tuesday 17th September 2002 at the Sutton Arms, starting at 8.00pm sharp.
You may recall that Richard, G0EWH mentioned the RA roadshow last year. If you have not heard about it for this year, the Midlands event is taking place on 31 October 2002 at the Hilton National, Coventry. It's a free event (including lunch), but you need to register on 020 7720 4411 or via the Web on www.joiningin.org.uk (or www.radio.gov.uk).
WyrePak now has a presence on the Communigate community website. See www.communigate.co.uk/worcs/wyrepak. Links from other parts of this site will also take you to our main WyrePak website, run by Paula at Blueyonder - go to www.g8pzt.pwp.blueyonder.co.uk/ wyrepak/. The WyrePak website has been updated and suggestions are invited from members for new links and ideas for content.
Why have two websites? I'm all for publicity, and the Communigate website is designed to catch the surfer who may be searching for local information, not particularly looking for ham radio related stuff. It is quite interesting!
Plenty of activity since the last Newsletter and the meetings have been attended, on average, by six members.
Present: G8BKL, G8PZT, G4SPZ, G0MBG, G3KFD, G0EWH
Apologies: G4YUD, M0BRU, G0HTF
Phil G4SPZ noted that Kanga Products (www.kanga.demon.co.uk) were advertising in the G-QRP Club journal "Sprat" a PSK31 Interface kit for œ23.95 (optional case œ9.95 extra). This is likely to be almost identical to Richard's home-brew interface demonstrated last month. Surprise was expressed at the high cost of the Kanga kit.
The antenna working group is now planning to overhaul the rear mast in the Autumn. The antennas on this mast are the 144.850MHz end-fed, the 70cms links to BHM and TELFORD (which may be redirected), the HB9CV on the 144.975MHz port, and the 23cms link to WV. New U-bolts and T & K brackets are available and rawlbolts will be obtained.
Richard and Paula reported on the successful Packet Conference which took place on 13th April. A full report and minutes appears on the Fourpack website - there are links to Fourpack on our websites. Additional information is available via the Internet at www.morcov.co.uk/ packet.
Paula mentioned that BBS activity continued to decline. At GB7PZT, over the last five years, bulletin downloads had fallen from 300 per day to 50 per day, and private mail messages were down from 300 to about 70 per day. The members present at the meeting felt that private mail was of primary interest, with only two members who regularly downloaded and read bulletins.
Present: G4SPZ, G8PZT, G0HTF, G0MBG, G3KFD, G8BKL
Apologies: G0EWH, G4YUD, M0BRU, G1DYC
The antenna working group is now planning to overhaul the rear mast at G8PZT given a clear, bright and dry day. The antennas on this mast are the bent C5 vertical (to be replaced by the 144/432/1296MHz triple-bander already purchased), 144.850MHz end-fed, the 70cms links to BHM and TELFORD (which may be redirected), the HB9CV on the 144.975MHz port, the 70cms test antenna and the 23cms link to WV.
It was agreed that the best way to tackle the project was for Richard G0EWH to initiate a call-out by telephone of the following members, who were available to participate for the day: G8PZT, G3KFD, G0MBG, G0HTF, G8BKL. Telephone numbers will be circulated by e-mail by G4SPZ. G0MBG and G0HTF volunteered to climb the ladders and G4SPZ regretted that he would be unable to help, being busy at work to pay for the pensions of the entire antenna working group. Thursdays should be avoided, together with the last week in June.
In his absence, Richard G0EWH was also elected as Site Foreman and Quartermaster, and a list of materials was agreed.
The meeting authorised the Treasurer to place an order with H Westlake for one ten-metre length of Westflex 103 ready-fitted with one male and one female N-type connector. This is for the triple-band vertical antenna to maximise performance on 23cms.
Members and others are asked to avoid telephoning the Sysop for general advice, particularly in the evenings - a request for advice via Packet or e-mail is far more acceptable, and will be responded to as soon as time permits. Telephone calls are welcome at any time, however, when users wish to report faults or problems with the BBS, the node or any of the radio ports.
Phil G4SPZ invited any contributions to future Newsletters. The Autumn 2002 fifth edition of the WyrePak Newsletter will be published in August.
Present: G4SPZ G0MBG G3KFD G0HTF G0EWH G8BKL*
Apologies: G4YUD M0BRU G8PZT G8BKL*
*Eric G8BKL joined the meeting at 2100 hours by means of a Packet Radio link from Watchet, Somerset via the Worle and Kidder nodes, the WyrePak equipment at the Sutton Arms being a Compaq Contura Aero 486DX 33MHz colour notebook computer running DOS6.22, BayCom 1.50a, a Maxpak BayCom modem and an Icom IC-W21E dual-band handheld at 2 watts on 432.675MHz.
Richard G0EWH confirmed that the following materials for the antenna overhauls were available:
Richard G0EWH provided a brief Treasurer's report to the effect that the accounts stood at œ92.62 after the purchase of equipment for the antenna upgrade.
...due to the absence of the Secretary on a (rare) holiday, no minutes were taken.
Present - G4SPZ, G0EWH, G3KFD, G0HTF, G0MBG, G8PZT
Apologies - G4YUD, G8BKL, G1DYC, M0BRU
After considerable discussion it was agreed that the antenna working party would assemble at G8PZT at 10.00am on Thursday 29th August 2002 to undertake the overhaul of the rear mast. STOP PRESS... STOP PRESS... Antenna system overhaul completed! Full report in the next edition of WyrePak Newsletter.
Richard G0EWH reported that John Scott G8UAE has agreed to take over the role of WyrePak auditor from the late Don G0ASR. A full treasurer's report on the audited accounts for the last 18 months will be presented at the AGM in September.
Phil G4SPZ reported on recent packet operation at a special event station in close proximity to a 100watt HF CW station, where the CW caused modulation of the packet signals. This was thought to be due to RF getting into the (un-screened) BayCom modem - see "Packet Clinic".
The intention of this section of the Newsletter is to summarise the relevent information which is made available at the WyrePak meetings. I have tried to avoid duplication and to omit items which are out-of-date, whilst providing readers with a good impression of what happens in a typical three or four month period - generally quite a lot! - Ed.
The link to GB7IPT in Telford failed in April due to the Sysop Richard G8JVM turning off his system and reportedly dismantling the antennas. This has led to the loss of the Internet link (but see "Developments")
WyrePak member John G1STL reported difficulty in accessing the 70cms port on 432.675MHz. Paula confirmed that the temporary Tait 500 transceiver is far less sensitive on receive than the Kenwood 8400 which was awaiting repair, pending the acquisition of a workshop manual. It was suggested that G1STL tries to access KIDDER via MLVN in the meantime, as the link to KIDDER is now much better following the antenna repairs. Richard suggested that G1STL also tries the WODEN node with ports on 144.850 and 433.675MHz as a route to KIDDER.
The same Tait 500 transceiver also acts as the link to DY72 at Dudley, which has also been unreliable. The 432.675MHz antenna was due to be replaced which should improve the port's performance somewhat.
The links from KIDDER to the GLOS, MLVN, TELFORD and CLEE nodes were originally designed to be full-duplex using TNCs in KISS mode running BPQ software. However, Paula has discovered that the TNC firmware was only enabling half-duplex operation, inhibiting receive whilst transmitting. The frequencies for these links can be seen in the Fourpack Manual to be at the opposite ends of the 70cms band to minimise de-sensing, so that full-duplex would be viable. The program has now been modified and full-duplex is in operation at 100% speed for the first time.
The problems with the link to GLOS have been investigated further and found to be due to problems with the audio on the link radio which fades out over a few seconds, and there is also a noise problem with the associated TNC. Repairs are being undertaken as time permits.
The Gloucester Repeater Group's link between GLOS and FOD has an intermittent fault which is being investigated.
The poor performance of the GLOS - FOD full-duplex 23cms 9,600 baud link was believed to be due to an intermittent fault in the transmitter at GLOS. This is an ongoing issue for Fourpack.
At KIDDER, the 70cms user port on 432.675MHz is now running with a new 25 watt Maxon radio, throttled back to approved power levels, which is much more sensitive on receive than the previous Tait transceiver despite having an IF designed for 12.5kHz channel spacing. The link to DY72 at Dudley is now working again, and all reports on 70cms would be appreciated by Paula.
The transmit audio fade-out problems previously reported on the link to GLOS have now been fixed. This was found to be due to RF feedback through the chassis, and additional decoupling capacitors have been fitted. Retry rates have fallen as a consequence. The reduced signal from GLOS had made the received packets susceptible to degradation due to desensitisation from the companion transmitter. This desense was eliminated by converting and installing a 6 cavity duplexer in place of the existing 3 cavity unit.
Members are asked to bear in mind that 70cms and 23cms links are often affected by rain and foggy weather. The "link budget" - the difference between the available transmitted ERP and receiver gain, minus the path loss - on a typical amateur Packet radio circuit will often be far tighter than would be tolerated on a commercial point-to-point link, and the weather can adversely affect the retry rate. Typically, a retry rate of 5% or less on a link gives good performance, a 10% retry rate is acceptable, whereas a retry rate of 25% or more produces significant slowing-down of the link. Changes in the refractive index of the air due to temperature inversions on summer evenings can also cause radio waves to be deflected upwards, causing a reduction in signal strength or even drop-outs. Please be aware of these limitations before being tempted to blame the Sysop!
The newly-repaired Kenwood 8400 radio, and the TNC from the redundant TELFORD link, have been redeployed to commission a new 70cms link from Port 11 at KIDDER to Abdon Burf GB7WE-12, alias ABDN12 in Herefordshire, which has opened up a link direct to Chester. You have to connect first from KIDDER to ABDN11, then issue the command "C GB7CH" which will link the user to ABDN12 and thence via a 23cms link to the Chester FlexNet node GB7CH, which is run by the North West Packet User Group. NWPUG have invested heavily in FlexNet hardware and software which does not integrate directly with the usual NET-ROM software more frequently found on Packet nodes. FlexNet does not provide a NODES list, and users need to know the ID of other neighbouring NET-ROM nodes, connect to the chosen node via GB7CH, then request a NODES list. The NWPUG website can be reached via a link from the WyrePak website, and members are recommended to look on their site for FlexNet commands and instructions.
The service manual for the Kenwood 8400 70cms link radio has been obtained, and Paula has traced the fault to a dried-up 100uF decoupling capacitor across the display supply rail. This was replaced and full sensitivity was restored
The MLVN node is off-air at the time of writing, and hence mail to and from GB7GLO is flowing via alternative routes - without queues building up, thanks to the resilience of the network.
Some exciting new features have been added to the services provided at G8PZT. With effect from 19th August 2002, 24-hour broadband Internet access is running at GB7PZT and new ports have been added. Port 15 is an Internet-linked connection to ZL2AQY in Auckland, New Zealand, Port 16 goes to VE2PKT in Canada, Port 18 to Marlborough, NZ and Port 19 to Columbia, Minnesota. These are XROUTER nodes and bring an increased number of additional nodes into the table. CHAT is also available between G8PZT and ZL2AQY. More links may be set up in the near future.
Also from 19th August, Internet access direct to the BBS is possible using TELNET. TELNET is effectively a 32-bit TCP/IP terminal program as provided with Winpack and with Windows 95 and later operating systems, from which is launched from a DOS window. TELNET is included within XROUTER software which can be downloaded from Paula's website - try the new URL which is www.pzt.co.uk. From a suitably equipped PC with Internet access, enter the command TELNET 62.31.206.176/ which is the BBS address. The BBS will be displayed as a web page as demonstrated on previous occasions. It will be necessary to log-in with your callsign and password; the password will be different to any previously allocated, and interested users should request one from the Sysop.
Other useful TELNET addresses are 62.31.206.176:23 which is the node, enabling access to the radio ports from a PC over a telephone line, 62.31.206.176:88 which is the BBS, and 62.31.206.176:1448 which is the APRS server on its 144.800MHz RF port. This will display UI-VIEW information.
A new APRS Internet gateway (Igate) will be enabled to users as soon as the NoV is issued. Further information on this facility will be available shortly.
The new APRS digipeater at Cleeve Common on 144.800MHz is now on air, and making a big improvement to APRS operation in the area.
As with all new developments, reports and comments are welcomed by the Sysop or any member of the Committee.
The Fourpack Radio Club meets on the fourth Wednesday of every month at the its new venue, The Swan, Whittington, just on the outskirts of Worcester city. Hopefully this new venue will enable more members to attend the meetings. The Agenda concerns the whole Fourpack network, and its links to other groups outside the four Counties. WyrePak members are welcome to attend all Fourpack meetings. (The Swan is understood to serve real ales, too, and a personal visit of inspection will be made shortly to assess the quality and range... purely for research purposes, you understand - Ed.)
Recent /P operation using BayCom has proved interesting. During July, Phil G4SPZ spent a week on holiday in his touring caravan in the Herefordshire countryside, and found that Fourpack's CLEE node gave excellent coverage of the area. Working back to KDRBBS was straightforward, but going through CLEE and KIDDER nodes to obtain keyboard-to-keyboard contacts with individual stations and PMSs was more problematic. During the daytime there were few problems, but in the evenings, increased traffic made the network much slower and unexplained disconnections were frequent. This highlights the shortcomings, and proves that the Packet network is more efficient when used for its intended purpose - mail forwarding in non-real time!
Some brief experiments were also conducted into the true "mobile" capabilities of AX25 packet radio, and G4SPZ/M can report reliable communication at speeds of over 50 miles per hour!
The WOSTER low-power node was used to demonstrate Packet Radio to visitors to Martley Show on 17th July. The portable Packet station at Martley consisted of a 486 33MHz notebook PC and BayCom modem, linked by a 20-metre long CAIRO cable to a dual-band FM mobile transceiver running 5 watts to a magmount antenna. WOSTER is a low-power Fourpack node sited near Ronkswood in Worcester, and designed as a local service node only (its receivers are deliberately de-sensitised). Signals from WOSTER were good at Martley, and direct communication was also established keyboard-to-keyboard with WyrePak member Derek G3KFD in Kingswinford.
However, during this QSO Derek commented that some CW QRM was audible on the 2-metre frequency. This was from the adjacent 100-watt HF CW station being operated by Graeme, G0TNU, whose antenna was only 4 feet away from the Packet station! The situation was no doubt exacerbated by the fact that the BayCom modem in use at Martley was an un-cased Badger Boards version, as the proper "mobile" screened Maxpak modem had been loaned to another station. Derek was able to copy clearly the CW being sent by Graeme! The effect on the Packet link was interesting - the retry rate increased dramatically, up to 9 or 10 whilst the HF CW station was sending.
In this instance, the cause was immediately obvious, particularly as G3KFD was monitoring the audio on the Packet channel. Other instances of slow traffic or timing-out may not be solved so easily. I have always been an advocate of listening to what is happening on the channel, at low level, and when this is combined with a Packet system such as BayCom, which provides a real-time monitor screen of Packet traffic on the frequency, a powerful diagnostic tool results.
Whilst on the subject of BayCom, G4SPZ attempted to connect a modern BayCom modem to the DATA port of a Yaesu FT-5100 dual-band FM mobile rig at G4YUD. This should be very simple and only involves a 2-core-plus-screen cable connection, but unfortunately it didn't work! Received audio at the fixed level put out by the radio was too low to be decoded, and transmit input gain was insufficient for the levels generated by the modem. A conventional connection using 4-core cable to the rig's microphone socket proved satisfactory after a PTT problem was sorted out....
The version of the BayCom modem manufactured and sold by Maxpak includes a helpful resistor on the PCB between MIC input and PTT line, to enable the keying of most hand-held transceivers without the need for external components. The problem here was that the modem keyed the Yaesu FT-5100 PTT into transmit mode as soon as it was plugged in! It doesn't take much to key an FT-5100 (600 microamps as measured) and the on-board resistor on the Maxpak board was causing sufficient leakage current to flow to key the rig. Scrutiny of the circuit diagram of the Maxpak modem, followed by judicious application of the side cutters to the offending resistor, resolved the problem.
Finally, Richard G0EWH recently solved a problem with Geoff G0HHH's BayCom Packet station by careful adjustment of the transmit and receive audio levels. Listening to the on-air "sound" of the station again provided a pointer to what was wrong.
Winpack information - to inhibit Winpack's tendencies to download from the BBS of its own free will, go into the FILE menu and select "Selection List Editor" then delete all the times in this list. This will stop the auto-connect sessions.
G0EWH writes: The secretary has asked if I can write some further tips as a user of Winpack. Where do I start? Winpack is an easy program to use, once you have set it up for your own station and all the necessary parameters that are needed, the main ones being call sign, frequency, mode, various BBS parameters to name but a few. There is a specific help document for setting it up for use with GB7PZT so that all the automatic features can be used. One of the main items that must be "checked"on the Options Menu is the "Auto Log" so that all connects are logged for you. There is a very good help file with Winpack and Ralph Milnes, KC2RLM has written a User Manual of just over 200 pages that is very good, this can be downloaded via a link on Roger's web site http://www.peaksys.co.uk/.
There are also a number of little "add-on" programs that have been written to help manage various housekeeping activities, the main one being WINPLOG which shows you the log file contents and has an option to remove and save 500 entries to an archive file. Another is WINPMAIL, this allows you to look at all sent and received mail with options of saving or deleting. Using the automatic mail functions, all sent mail seems to "disappear" once the system has sent it, but it is still on your PC, saved in a specific Winpack folder, WINPMAIL is an essential little tool. There are others which I can advise you on for those wishing to explore Winpack further.
The latest version of Winpack is 6.80 and is still a 16 bit program so works under Windows 3.x (Good! - G4SPZ) right up to Windows XP. The actual setup will depend on what you are using for a TNC and how this is interfaced with Winpack. For standard TNCs any system will accept these, but if you wish to use BayCom or a soundcard, then it's best to use AGW Packet Engine which needs at least Win95, although there are limitations with WinXP regarding no drivers yet for some modems such as Baycom and YAM.
Richard G0EWH
That's all for this edition, folks. Thanks for reading!
WyrePak Newsletter is compiled, edited and published by Phil Harris CEng MIEE, G4SPZ, 22 Bramley Way, Bewdley DY12 2PU 01299 403025. The chap below bears no resemblance to G4SPZ, having a far fuller head of hair, but G4SPZ's clip art directory lacks a better likeness!
Please forward items for inclusion in the Newsletter by e-mail to g4spz@aol.com or by Packet to G4SPZ @ GB7PZT.
(c) G4SPZ 2002