COHERENT C.W. NEWSLETTER@ I - MMIN Compiled by G31RM Issue number 30 December 1994 Postage stamps The stamps this time are, of course, the usual Christmas special issue. Publicitv The editor of the R.S.G.B. magazine RadCom has confirmed that my article `CCW and DSP` briefly outlining the history of CCW and describing the COHERENT program will be published in the near future. I was surprized to read in his letter that they pay for articles and the proceeds should cover the expenses of the Group for some time so it is unlikely that I shall be asking for contributions for quite a while! Mailing list DF3CT DJ2ZV DJ6EC DJ7HS DJ7PO DKSOK DU BEY DU ST DU EBE DI ;,MG DL2NI DL6DCS DL6YCG EA2SN EA8YU GOSHA GOPMN G3AAJ G3CCH G3EGQ G3FMW G3FVC G3IRM G3MND G3NCL G3RHI G3RNB G3SBI G3TFV G3WBI G3XHQ G3XVR G3ZQS G4DWC G41-RA G40KO G4SYC G4VSO GM3YCG GWONSZ GWOPNE HB9DDO HB9KAT KOLR K6ARE K9GVVT KBOEBG N2HOS OE5EEP OE6WTD SIV16FPC VE21Q VE3DPS VE30XX W1AEL W2RV W6HDO W7GHM ZF1HJ ZL2BHV ZSiAAZ arid three short wave listeners - Bandera, Black and Rinetti. COHERENT boards and programs The following have the COHERENT kit: DFiAE DF2KB DJ2ZV DJ7HS DJ7PO DK36U DK4BY DKSOK DUBEY DUBT DL2AD DL2FI DK6KL EA2SN G3CCH G3IRM G3XHQ HB9DD0 lK2HKS KOLR KC7WW KD41DY OE6WTD VE21Q VE3GF VE30XX WiAEL W2RV W6HDO WA4TNV ZSiAAZ and one short wave listener - Knebel. European beacon Alfred DJ2ZV now has a CCW beacon in operation. He will run the beacon every Thursday at 2000 UTC on 10,131 Khz until 2030 and then on 7,031 Khz until 21 00. The beacon will consist of the usual sync pulses followed by text for 96 seconds. Os] cards are available for sending in copies of the fully decoded text. Power output will be less than one watt to a dipole antenna. Even if you cannot receive CCW using the Petit filter or the COHERENT program please listen and see if you can copy Alfred's transmissions and let him know 11' you hear anything. Operating frequencies Franco, 11-10037, tells me that Italian stations are only allowed to use 1 0, 1 00 to 1 0, 1 1 0 Khz so our suggested frequency in the thirty metre band is outside their allocation. He has offered to translate my article in Radio Communication into Italian for their magazine Radiorivista subject, presumably, to the approval of the R.S.G.B. W2RV tests Due to poor conditions Dave abandoned his tests but he has managed a few contacts with Bill de Carle on both twenty and thirty metres. Signals were only Si to S3 though there was no trouble in copying or staying on frequency. To be sure he is on frequency Dave uses an old Radio Shack model 100 computer that reads frequencies in one hertz steps from his Kenwood TS-850S. Drift was five hertz or less during the contacts. In actual fact, due to the low static level, Dave could copy Bill better by ear as he could guess the existence of dots and dashes during fades and, as COHERENT sometimes triggers during fades he comments that "you don't know whether to believe it or not". Comments from Alf DLi ST Alf has a transceiver which only tunes in ten hertz steps and considers it is not suitable for use with COHERENT. However, he has had the use of a TS450S for a while but now has a TS-850S. In addition he has a W9GR filter which he recommends and I can vouch for that remark as 1, too, have one and am well pleased with its performance. He also comments that he does not think COHERENT will be very popular with the low power operators as many of them do not have computers and are not particularly interested in them either. This will tend to exclude those operators who were likely to use CCW in the past. Although I think he has a valid point, there are others who are not low power operators and have the equipment to run the program. One of the main attractions of the program is that there is very little building to do as opposed to the old days of the hardware filter. Everything needed can now be bought ready for use. He also enclosed a list of tuning rates for some transceivers which is well worth including here. The following have one hertz tuning: KENWOOD:TS-950, 850, 690, 450 ICOM:IC-736, 737A, 738 JRC:JST-145 Thenormal ICOM 737 is not included TheJRC-245 tunes in two hertz steps AllYAESU transceivers known to Alf tune in ten hertzsteps. Additions to this list will be appreciated. Alf is also trying for more publicity for CCW and has an article to be -published in the German, magazine Funkamateur. It was due in the November issue. Future tests Alfred DJ2ZV has written to say that he and Hajo DL2AD both have the COHERENT program running and have had several contacts on 10,131 and 7,031. He uses a Kenwood TS-940S and Hajo uses a military transceiver with temperature compensated crystal oscillator. Both stations now feel that they can look out for contacts with other stations. This is, of course, in addition to the beacon operation mentioned above. Fluke RF signal generators John G3FMW has obtained a Fluke frequency synthesizer model 6160A which, unfortunately, appears to have a small fault. Does anyone know where details of this piece of equipment can be obtained? Apparenth, the manufacturers can no J, longer supply service manuals. If you can help in any way please contact John at 22 Manor Gardens. Killinghall, Harrogate, HG3 2DS. infrared CCW John G3CCH has recently been using COHERENT to "clean up" signals from an infra-red receiver when using MCW. The set-up is quite simple - a low frequency (around 6OKhz sub-carrier is modulated by a stable 80OHz audio oscillator. The keying of the audio oscillator is done by Bill de Carte's keyboard with timing coming from a divider chain from the line oscillator of a TV receiver (tuned to a station). This sub-carrier modulates four infra-red diodes. It is difficult to say how much infra-red power is there but it can only be a few tens of milliwatts. The receiver is two (in parallel) receiving infra-red diodes with pre-amplifier feeding into a simple FM receiver. The audio output can be listened to directly or via the computer using COHERENT. Even the very noisy signals from the receiver can easily be read by the CCW program. To increase the 'DX" lenses are fitted to both transmitter and receiver. These are 1.reading sheets" purchased very cheaply at the local library intended originally for people with difficulty reading print in books. They are just a lenticular cut lens of plastic sheet. The size is about 10" x 8" so the cases for transmitter and receiver are quite large when you realize that the focal length of the lenses is approximately 12". Because the distance between the transmitter and receiver is limited by the length of the garden John has been playing around with attenuators at the receiver reducing the effective lens area by probably more than 90% and this still results in strong signals at about 20 yards. John next intends to change the sub-carrier to AM even though he is fully aware that daylight may easily swamp the receiver - it can also swamp FM. He has been making good use of the FFT program to look for weak signals out of the infra-red receiver. He has also been trying tape recording CCW signals but (as one might expect) due to minor variations in speed between record and replay the signals fade in and out as the phasing changes. The COHERENT program John Stace has asked if there have been any updates to the program recently. The latest I have is version 2.3. Perhaps Bill can let us know if 6e has made any further amendments. Abuse of the English language For a long time now I have wondered whether or not I should comment on one of my favourite subjects - the abuse of the English language. There have been three articles I have seen recently in the amateur press pleading for better English, so let me add something. What I am complaining about is the abuse of the language by the English. Americans have their own version and some of the English I read and heard from foreigners is better than that from native speakers. Perhaps in future I will add a few examples now and again. Here is one I heard recently from a television reporter describing how to enter the National Lottery. First you fill out [in] the form and then hand it in to be computered [entered into the computer]. My suggestions are in brackets. A HAPPY CHRISTMAS AND ALL THE BEST FOR 1995 de G31RM