C:@ - C@ - W - " *-- " Ea I -_@- -=,. t-t a-- 4!5=)@ C-_ C:3 M F3 1 X C-_ CJ t3 (:3 =-, X F:R M Publicity :::: X ' Bernhard's translation of my short artiEle in Sprat has been printed in C9-DL - I know because the enquiries have started cooing in. I New members :::: DJ3AM Prof. Walter Gielessen Retnhir@ Lipkow Depkenstr. I I!Qistelwinkel 1 0-2800 Bremen I D-3016 Seelze I 63CWI Richard Newstead 640KO ' 6ave Rycraft 6W3DEX Norman Howard On the air :::: Bob Carter 64VSG isthe first UK station to be ready for operation. If anyone is able to receive CCW will they please contact his.Or better still, is anyone near being able to join hit on the air? His address is: 2 Victoria Road,Cavershas, Reading, Berks R64 79Y. Comment :::: Cohereni CW - June 1990 :::: Where do we stand? :::: Where do we go from here? :::: By Bert Arnold 63RHI :::: In May !989 in response to a plea on behalf of Coherent C.W. by G3RHI in 'Morsum Magnificat', 63IRM wrote to hit. J SSE sked was set up and both agreed to build a CCW rig using the Woodson 9ST article of May/June 1981 as a guide. The rigs are SOZ complete and very recently 63SBI and 60SO, haying developed some new CCW circuits, have joined the duo. With the intention of assessing responses fros a wider group 63RHI talked to the May 1990 GRP Convention arranced by the Yeov@l club on 'CCW - What, How and When?' He hoped to raise a recruit or two and find a technical gen person who light enlarae the team. No technical gen man appeared though one possible recruit may join the group. It seems unlikely that the G-QRP Club will play an active and leading part in developing the mode. In addition to building GJ71RM began recruiting. This included a full list of publications with duplicated copies available to those who asked at five pence a sheet and a CCW Newsletter of which this is the sixth issue. He his listed the interested holders' callsigns in these letters which could help builder-, to see if these is -someone else n;arbv. since without doubt, this is a project for which it is most helpful to co-operate with two or three others either by SSE skeds or. better still, personal contact. So far 52 amateurs have contacted G31RM. There are 74 UK stations and IS oyerse2s operators who are AKOB DFXT Dj3AM Dj4SB DKIIO EA2YU FILCI F61YT KSIXZ HB90DO VE2KN VE'DPR YE70BE WUAT W76HM ZFIHj ZL!8TT 'A21F. Vital information about progress is difficult to come by. People say not report back for mode months. if then. Being ready for a 9SO usually brings an enquiry and priority must be given to making this possible with a fixed tine and frequency on at least one band.Details for working this out are suggested below. At the other end there are those who have done nothino and forwhich there ea- be very good reasons. Progress by individuals has been recorded in r the newsletters but oriority should be given to listing those for whom operation is in sight - -,By three months or less away. For the past twelye months G-@IRM and 67RHT have had a weekly sked on Friday- on 7060 KHz at If a.m. local time. This is not a convenient time except for the retired. Anyone is welcume to join in from !1.30 a.2. 6_31RM 63R,41 6131SPI and 64VSO are hoping to arrange a Sunday morning 5ked at 9.70 a.m. local time an 3772 Uz. Again you are welcome to Join but please give us thirty minutes to deal with business. fff Note by 63IRM: It is difficult for se to get o6 80 2etre5 but we shall see. fff and 64VSG have made a number of changes to the Woodson circuits. The other two have usually followed Woodson.If we are to finalise and publish a design discussions must take place. The recommended design must be sure to work,preferably be aiyer, credibility with three months operating and., id eally, PCBs made. For PCB production we urgentlyneed a technic;l gen man able 'to desion and sake the boards and. as with all development work, lose money doing it. Art early decision was made to operate or.. 7030 KHz for a start. This is the recommended 9RP Club frequency and a fixed time and day for 9GOs is suggested. How about 1! a.m. local time on Sundays? For other bands it has been suggested that 30 KHz up from the bottom of each band should be used. 7030 KHZ should allow easy UK contacts with olenty of 9RM to severely test the system together with a good possibility of European GGOS. Assuming night operation is oossible North American stations should be workable. Some contents on circuit progress so far follows with an eye an the finalised design. Itet numbers refer to GjIRM's bibliography. fff Bert included a block diagras but there is insufficient space to include this - you should Master oscillator W6NEY's UST article suggested that all subsidiary synchronising frequencies should come from this oscillator, not essential but desirable. An oven-cospensated crystal oscillator is a solution but a means of checking its accuracy has led to the suggestion of replacing it using the Droitvich signal nudged from 198 KHz to 200 KHz as a standard (Ites 23). Other stations like DU can be used. Dividers Standard five and two dividers do the job with five volts perfectly. The outputs are TTL levels and need a level shifter where they synchronise the plus and sinus levels of the 10 Hz filter. If just starting it would in advantage to design the standard and its dividers and the filter to operate from similar power rails. Woodson never satisfactorily faced this problem. The VE30BE keyboard (Ites 7) works well though it lacks the message memory facilities featured in present day designs. Recently 63SBI has programmed an Altera EP610 to produce a paddle-operated keyer synchronised to the standard (contact 63SBI). 10 Hz filter So far no alternative to W6NEY's OST article (based on the original W76HM design) has been developed though the addition ofan audio synthesiser for fine tuning (not described by W6NEY) has been made (Ites 4). 64VSO has produced a simplerbut effective design to replace 63IRM's ites 4 design. Details are given as information sheet 30 in this newsletter.63SBI also hopes to program an EPLD to make an even simpler design. Synthesised oscillator This has proved the most time consuming. 63IRM 63RHI and 64VSG all purchased an MCI45151 from Cirkit in spite of the price intending to use an 8 KHz synchronising signal in place of the crystal to produce 7030 KHz output. This unit has the big advantage of BCD switching to shift the frequency from 7024 to 7039 KHz in I KHz steps via four switches. The snag case with the lock-up time which needed one to two seconds recovery when switched. Thus the transait!receive switching clipped the first characters on transmit and receive. A delay on changeover would avoid this. Both 63IRM and 64VSG worked for a long time at curing this. Both stations avoided the Cirkit board thus reducing cost to almost half. 64VSO's answer is the better one (now copied by 63IRM) and is included in this month's information sheet. Transmitter and receiver The synthesised oscillator made direct conversion set-up the most attractive for both. There are many circuits for ordinary CW which, if carefully built, should work. There is more room here for experiment than anywhere else. If using an existing rig it oust meet the such higher standards of CCW. They are unlikely to do so as they stand' Finally to sum up 63SBI's efforts, Colin hopes to sake a compact unit using EPLI)s comprising a paddle kever, an audio s-nthesiser and 10 Hz filter - three i.cs. in all in a 6' square box. I Coherent FSK :::: G3XVR and VE30BE are considering the possibility of using two audio tones separated by 10 Hz using identical detectors and comparing the outputs. A theoretical 3) db gain should be obtained. It will still work mitt, CCW by comparing the signal with noise in the other channel. I-- Information sheets :::: 30.The G4VSG collection This is a set of four diagrams used by Bob. The first sheet is the r.f. synthesiser and uses an MC145151, a CA3140 and six transistors. It is easy to adapt the circuit for a coverage on 5 MHz for use with a 9 MHz filter. A single BCD switch covers the I KFz steps with a single pole switch to give the additional 500 Hz shift if needed. It locks to the standard on 8 KHz via an additional divider on the audio board. Two further sheets cover the audio synthesiser and require eleven i.cs. and just two transistors. The fourth sheet is simply a replacement for the 74C74 devices in the Woodson article as quadrature generators using C04013s. (4 pages) I have a brief data sheet on the MC!4515! Q pages) and the Cirkit design sheet (4 pages) if anyone is interested. News from members :::: DF3CT:Bernhard is still making progress having completed the audio 5ynthesiser. He made one small modification to set the centre frequency of the display which others may find helpful. Add a 4K7 resistor between the 4K7 trietiot and zero volts. 639OU:Bill's wife is disabled and needs constant attention thouch he is managing to get the keyboard built. 63SBI: Not a lot of interest reoorted yet regarding Colin's chip. It's good' S__1XVR:Danny appears to have made a leap forward with the r.f. side having recently acquired a military sanpack set covering h.f. With a good standard added he hopes this will complete the tx1rx. 64 L R r4: Good progress reported with the filter and audio synthesiser working - r.i. synthesiser next. Gary had problems balancing the filter getting a continuous low level I KHz note all the time - adding a couple of 100K ure pots. to the hold circuit 3130s c. d it. He is trying to tie in a computer to the system. 64VSLI- Bot's activities have resulted in the data sheets mentioned above. 73 de 63IRM