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“Paranormal ejectronies - (subliminal;perception test Kirlian phatograi ' “biorhythm calculato! Sã 18 Ad A-4 — elektor october 1977 decoder eleitor dO decoder Volume 3 Number 10 Editor : W. van der Horst [paris FUN Ceni é Deputy editor P. Holmes Leo usually replaced by one of the Ê ! following abbreviations: Technical editors : J. Barendrecht Apa Ana ua Rates, o! G.H.K. Dam What is a missing link? n (nano-) ) E. Krempelsauer Semiconductor types Very often, a large number of G.H. Nachbar equivalent semiconductors exist A. Nachtmann with different type numbers. For this reason, 'abbreviated' type A few examples: Fr. Scheel numbers are used in Elektor Resistance value 2k7: 2700 22. K.S.M. Walraven wherever possible: Resistance value 470: 470 92. C. Sinke *:741' stand for uA74!, Capacitancs value 4p7: 4.7 pF, or Art editor à | : Mrs. A. van Meyel U.K. editorial offices, administration and advertising: Elektor Publishers Ltd., Elektor House, 10 Longport Street, Canterbury CT1 1PE, Kent, U.K. Tel.: Canterbury (0227)-54430. Telex: 965504. Please make all cheques payable to Elektor Publishers Ltd. at the above address. Bank: 1. Midland Bank Ltd., Canterbury, A/C no. 11014587 Sorting code 40-16-11, Giro no. 3154254. 2.U.S.A.: c/o World Way Postal Center P.O. Box 80689, Los Angeles, Cal. 90080, AIC no. 12350-04207. Assistant Manager and Advertising Editorial : R.G. Knapp : T. Emmens Elektor is published monthly on the third Friday of each month. 1. U.K. and all countries except the U.S.A.: Cover price £ 0.45. Number 27/28 (July/ August), is a double issue, “Summer Circuits”, price £ 0.90. Single copies (incl. back issues) are available by post from our Canterbury office, at £ 0.60 (surface mail) or £ 0.95 (air mail). Subscriptions for 1977, January to December incl., £ 6.25 (surface mail) or £ 11.— (air mail). Subscriptions for November and December 1977 £ 1.05 (surface mail). 2. FortheUS.A.: Cover price $ 1.50. Number 27/28 (July/August), is a double issue, “Summer Circuits', price $ 3. Single copies (incl” back issues) 8 1.50 (surface mai $ 2.25 (air mail). Subscriptions for 1977, January to December incl., $ 18.— (surface mail) or $ 27.— (air mail). Subscriptions for November and December 1977 $ 3.— (surface mail). All prices include post & packing. Change of address. Please allow at least six wooks for change of address. Include your old address, enclosing, if possible, an address label from a recent issue. Letters should be addressed to the department concerned: TQ = Technical Queries, ADV = Advertisaments, SUB = Subscriptions; ADM = Administration; ED = Editorial (articles submitted for PS = Elektor printed circuit board service. please enclose a stamped, addressgd envelope. The circuits published are for domestic use only. The submission of designs or articles to Elektor implies permission to the publishers to alter and translate the text and design, and to use the contents in other Elektor publications and activities. The publishers cannot guarantee to return any material submitted to them. All drawing, photographs, printed circuit boards and articles published in Elektor are copyright and may not be reproduced or at in whole or part without prior written permission of the publishers. Patent protection may exist in respect of circuits, devices, components lentify such patent or other protection. National advertising rates for the English edition of Elektor and/or jonal advertising rates for advei 1g at the same time in the EM HSD ME ond Cio irado pre malta on req Distribution: Spotlight Magazine Distributors Ltd, Spotlight House 1, Bentwell Road, Holloway, London N7 7AX. Copyright O 1977 Elektor publishers Ltd — Canterbury. Printed in the Netherlands. LM741, MC641, MIC741, RM741, SN72741, etc. e 'TUP' or 'TUN' (Transistor, Universal, PNP or NPN respect- ively) stand for any lowfre- quency silicon transistor that meets the following specifi- cations: UCEO, max 20V IC, max 100 mA he, min 100 Prot, max 100 mw fT, min 100 MHz, Some “TUN's are: BC107, BC108 and BC109 families; 2N3856A, 2N3859, 2N3860, 2N3904, 2N3947, 2N4124. Some 'TUP's are: BC177 and BC178 families; BC179 family with the possible exeption of BC159 and BC179; 2N2412, 2N3251, 2N3906, 2N4126, 2N4291. e 'DUS' or 'DUG! (Diode Univer- sal, Silicon or Germanium respectively) stands for any diode that meets the following specifications: Some 'DUS's are: BA127, BA217, BA218, BA221, BA222, BA317, BA318, BAX13, BAY61, 1N914, 1N4148. Some 'DUG's are: OAB5, 0A91, OA95, AA116. *'BC107B', 'BC237B', 'BC547B' all refer to the same “family of almost identical better-quality silicon transistors. In general, any other member of the same family can be used instead BC107 (8, -9) families: BC107 (-8, -9), BC147 (8 -B), BC207 (-8, -9), BC237 (-8, -9), BC317 (-8, -9), BC347 (8, 9), BC547 (-8, -9), BC171 (-2, -3), BC182 (3, 4), BC382 (-3, 4), BC437 (-8, -9), BC414 BC177 (:8, -9) families: BC177 (8, 9), BC157 (8, 9), BC204 (-5, -6), BC307 (-8, -9), BC320 (-1, -2), BC350 (1, 2), BC557 (8, -9), BC251 (-2, 3), BC212 (-3, 4), BC512 (-3, 4), BC261 (:2, -3), BC416. Resistor and capacitor values When giving component values, decimal points and large numbers 0.000 000 000 004 7 F . Capacitance value 10n: this is the international way of writing 10,000 pF or .01 uF, since 1 nis 107? farads or 1000 pF Resistors are % Watt 5% carbon types, unless otherwise specified. The DC working voltage of capacitors (other than electro- Iytics) is normally assumed to be at least 60 V. As a rule of thumb, a safe value is usually approxi- mately twice the DC supply voltage. Test voltages The DC test voltages shown are measured with a 20 k92/V instru- ment, unless otherwise specified. U, not V The international letter symbol *U” for voltage is often used instead of the ambiguous 'V'. *V"is normally reserved for “volts”. For instance: Up = 10 V, not Vb = 10 V. Mains voltages No mains (power line) voltages are listed in Elektor circuits, It is assumed that our readers know what voltage is standard in their part of the world! Readers in countries that use 60 Hz should note that Elektor circuits are designed for 50 Hz operation. This will not normally be a problem; however, in cases where the mains frequency is used for synchronisation some modifi- cation may be required. Technical services to readers * EPS service. Many Elektor articles include a lay-out for a printed circuit board. Some — but not all — of these boards are avail- able ready-stched and predrilled. The 'EPS print service list! in the current issue always gives a com- plere list of available boards. * Technical queries. Members of the technical staff are available to answer technical queries (relating to articles published in Elektor) by telephone on Mondays from 14.00 to 16.30. Letters with technical queries should be addressed to: Dept. TQ. Please enclose a stamped, self addressed envelope; readers outside U.K. please enclose an IRC instead of stamps. . link. Any important modifications to, additions to, improvements on or corrections in Elektor circuits are generally listed under the heading “Missing Link! at the earliest opportunity. 10-04 — elektor october 1977 paranormal electronics normal blaci We hasten to reassure our readers, lest our use of the word “paranormal” should conjure up visions of unspeak- able hags dancing around cauldrons with uneatable contents, or of bats capering around the crumbling crenellations of crepuscular Carpathian castles. We are not attempting to delve into the occult, but on the other hand the articles that will be presented in this and the next issue are not a series of “trick or treat” gimmicks for Hallowe'en. What we are attempting to do is to take a look at some phenomena that are on the fringes of our normal experience, such as the physiological effects of electric and magnetic fields, biofeedback, sub- liminal perception and precognition, Kirlian photography and so on; areas of investigation in which electronic circuits have many applications. Some of the claims made for these phenomena are now beginning to gain acceptance in scientific circles, others are still treated with scepticism and still others have been discredited. We make no judgements either for or against these claims, we simply provide readers with the means to carry out their own experiments. That scientific recognition of many of os e ) / these phenomena has been slow in coming is no doubt due, in part, to the fact that many of the experiments which have been carried out have been distinctly unscientific in character. Much of the equipment that has been used in the past was ill-designed and undoubtedly lent its own bias to the results of experiments, so what we have attempted to do is develop circuits that will function reliably and safely. Whilst every attempt has been made to ensure adequate electronic perform- ance of the circuits described, and experts in various fields have assured us that the use of these circuits presents no danger to health, we cannot guarantee the validity or effectiveness of any experiments in which the circuits are used, nor can we answer any queries except those concerning the electrical operation of circuits. For example, the “loniser” described in this issue produces a stream of negative ions which — it is claimed — have a beneficial effect. Whilst we can offer advice should the equipment fail to produce negative ions, we cannot offer any assistance if readers do not feel better after using it! LL] Kirlian photography elektor october 1977 — 10-05 Kirlian photography is not a recent invention — indeed it has been practised for about 50 years. The basic Kirlian equipment consists of a metal plate which is connected to a high voltage AC source. On top of the plate is placed a sheet of insulating material on which the photographic plate is laid, emulsion side up. The object to be photographed is placed on the photographic emulsion and the plate is 'exposed” for several seconds, then developed in the normal fashion. Kirlian photography gives the most pos- itive results if living objects are photo- graphed, such as the photographer's own hands, leaves, flowers, insects etc., and many proponents of Kirlian photo- graphy claim that the photograph is an indication of the “psychic aura” of the subject. However, a more likely expla- nation is that the effect is due to the moisture content of the object being photographed. Kirlian “cameras” are commercially avail- able, but they are extremely expensive, and a comparable home-made device can be built for a fraction of the cost. High-voltage generator The electronics of the Kirlian camera consist entirely of the high voltage generator, its trigger circuit and associ- ated power supply. The voltage required for Kirlian photography is in excess of 20 kV, and the simplest way to generate this is to make use of a car ignition coil, which can be picked up quite cheaply at scrapyards. The coil is driven by the circuit of figure 1, which is basically similar to an existing transistor-assisted electronic ignition circuit. When point X is grounded TI is tumned on, which turns on T2, and current flows through the primary of the coil. If a positive pulse is applied to point X T1 and T2 tum off, and the current through the coil primary decays rapidly. This causes voltage to be induced in the coil which is clamped to about 240 V by zener diode Dz. The secondary turns ratio of the ans that this voltage is stepped d 20 kV at the H.T. second- up toa ary terminal of the coil Pio Kirlian photography has little in common with conventional photo- graphy. The film is exposed, not optically through a lens system, but by placing the object to be photographed in contact with the film and placing it in a strong AC electric field. This article describes the construction of an inexpensive experimental Kirlian “camera”. Trigger circuit The trigger circuit (figure 2) consists of an astable multivibrator constructed around IC1. The non-inverting input of IC1 is biased to around two-thirds supply voltage, plus or minus the hyster- esis voltage provided by R3. If CI (or C2) is initially discharged the output of the op-amp will be high, charging C1 via R4 and PJ until the voltage across this capacitor exceeds the voltage on pin 3 of the IC, when the output will go low C1 will then discharge through R4 and PI until the voltage on CI falls below the (new) voltage on pin 3. When the op-amp output goes high TI is turned off, which turns off T2 and triggers the high-voltage generator. The frequency of the multivibrator may be adjusted by means of Pl and by switching between CI and C2. This can be particularly interesting when taking Kirlian photographs in colour, since altering the frequency of the electric field varies the colour of the final photograph. Power supply The circuit may be powered from a 12 V car battery, or for mains operation a simple stabilised supply may be built as shown in figure 3. The high-voltage generator requires a fairly high current but does not need a regulated supply, so its supply voltage is taken from point Ub. The low-current stabilised supply for the trigger circuit is provided by a regulator consisting of a zener diode D4 and series regulator transistor T3. Construction A printed circuit board and component layout for the high-voltage generator are given in figure 4, Resistor R3 is not re- quired in this application and is replaced by a wire link. The zener diode Dy is made up from a chain of 1W zener diodes, and the voltage of each diode is not critical provided the total zener voltage adds up to between 200 and 240V. Six 36V or 39V zeners are suggested. A p.e. board and component layout for the trigger circuit and power supply are given in figure 5. The only connections required between the two units are to kirlian photography elektor october 1977 — 10-07 5 IS 3 Parts list to figure 4. Resistors: R1=470/1W R2=100 0/1 W R3 = wire link R4,R5=33 92/10W Semiconductors: 1... D4=1N4148 D, = series combination of several zener diodes with a total zener voltage between 200 and 240 V/1 W, see text T1=BD 242 U11 Miscellaneous: L1,L2 = ignition coil (12 volt) 5 push-on connectors for the transistorised ignition system Parts list to figure 5. Resistors: R1,R3=47k R2=22k R4,R5=10k R6=2k2 RZ,R8 R 1k kz P1 = potentiometer 100 k/lin. Capacitors: C3,C4 = 4700 1/25 V C5=104M0V C6=474uh0V Semiconductors: D1,D2 = Si-diode 50 V/5 A D3 = 1N4148 D4 = 8V2/400 mW zener diode T1=BC557B T2=BC 141 T3=BC547B IC1=741 Miscellaneous: Tri =transformer 2x 12 V/1.5 A connect point X of the trigger circuit to point “Se” of the high-voltage gener- ator, and to connect the “O” and + out- puts from the supply to the “2” and “+Ub) inputs of the high-voltage gener- ator. The primary of the ignition coil is connected to the output terminals of the high-voltage generator, and the HT. terminal of the coil connects to the metal plate. In view of the high voltages generated, considerable care should be taken with the housing for the circuits, and fig- ures 6, 7 and 8 give some indication of the type of construction that should be adopted. The entire case for the proto- type was fabricated from acrylic sheet, which was chosen because of its good insulating properties. The box was made of 5 mm thick sheet, which is the mini- mum consistent with good insulation and reasonable mechanical strength. The lid and sides of the box should be made as a single unit, the circuits being mounted on the (removable) base. The metal plate is a piece of aluminium 300 mm x 200 mm and between | mm and 2 mm thick. The H.T. connection to the plate is made by drilling and countersinking a 3mm hole in one corner of the plate and inserting an M3 screw with countersunk head so that the head is flush with the plate. Nuts and a solder tag may then be attached, as shown in figure 9. To maintain good insulation the lid of the box must not be pierced with any holes, so the aluminium plate must be attached to the underside of the lid using epoxy adhesive. To allow good adhesion the acrylic sheet should be roughened with emery paper at the points where the adhesive is to be applied. Finally, to avoid the possibility of an electrical discharge tracking around the edges of the lid, the joints between the lid and the sides of the box should be sealed with silicone rubber. All the components with the exception of SI, 2 and Pl can be mounted on the base of the box, which can be attached to the lid/sides assembly either by a hinge down one edge or by screws into tapped holes in the box sides. Using the Kirlian camera To avoid fogging of the photographic film by light, Kirlian photography must obviously take place in total darkness. Any type of photographic film may be used, either monochrome or colour, but the plate should be of sufficient size to accommodate the object being photographed. The film is placed, emulsion side uppermost, on the lid of the box. The object to be photographed is then placed on the film and is weighted down with a piece of acrylic sheet. If a human hand is to be photo- 10-08 — elektor october 1977 Kirlian photography all dimensions in mm sea 8 Warning In view of the high voltages used for Kirlian photography, extreme care should be taken with the construction and use of the Kirlian camera. At the risk of being repetitious it must be stressed that the insulating lid of the box must be at least 5 mm thick and should have no holes in it, and the joints at the edges of the lid must be well-sealed. No metal screws should be used in this part of the construction. The controls P1, S1 and S2 should be adequately insulated types, with plastic spináles, knobs, etc. The camera should never be operated with the box dismantled, as touching the metal plate or H.T. terminal of the coil could result in à severe electric shock. Never use the camera in damp conditions, and especially do not try to process the film in the darkroom at the same time as using the camera, since using the camera with damp hands is inviting trouble. Finally, it is recommended that the Kirlian camera is not used by anyone suffering from a heart ailment. Figure 7. General view of the prototype of the Kirlian camera. Figure 8. Dimensions of the Kirlian camera. Figure 9. Showing the H.T. connection to the aluminium plate. Figure 10. Kirlian photograph of a fresh leaf. Exposure time 2 seconds, frequency 50 Hz. Figure 11. Kirlian photograph of three old leaves taken with the same exposure values as figure 10. o o o e a o o a = graphed this is simply placed palm down on the film, there obviously being no need for the weight. The camera is then switched on for an exposure time of between 1 and 5 sec- onds, after which the film is developed in the normal manner. No details of film development will be given as this is out- side the scope of the article, and it is assumed that readers who wish to experiment with Kirlian photography will already be familiar with normal photographic processes. When taking colour photographs the trigger frequency has an effect on the predominant colour of the photograph, and this effect perimented n be with by varying the setting of P1 and si. Figures 10 and 11 show the sort of results that can be expected. Figure 10 is a Kirlian photograph of a fresh leaf, taken with an exposure time of 2 sec- onds at a frequency of SO Hz, while figure 11 is a photo of three old leaves, taken with the same exposure con- ditions. Literature: J.0. Pehek, H.J. Kyler, D.L. Faust: Image modulation ir ; Photos tibia Sclen ce té tio? Val. 194 nr. 4262, p. 263. 10-10 — elektor october 1977 ecir tv pattern generator Figure 1. Block diagram of the sync gener- 14 ator. The blocks not assigned figure numbers have already been described. 4 MHz-X-tal - timebase + divider chain Figures 2,3,4,5and6. Gating circuits to derive line blanking, line sync, field equalis- ation, field sync and burst enable signals respectively. Photo 1. Line sync (lower trace) compared 25H to line blanking. | line blank (fig2) 25H 75H line sync. a E Photo 2. Field equalisation (lower trace) compared to line blanking. Photo 3. Field sync (upper trace) compared to line blanking. 2,5H field eq. (figa) field syne. ffig5) Photo 4. View of the complete video wave- form (lower trace) during the field blanking interval. Photo 5. Expanded view of the equalisation and field sync pulses (lower trace). sync. + video mixer ps À E. composite-wideo chroma subearrier video Parts list for figure 8 | Ee Resistors: J [iso R107... R111 = 4277 (supply line RA decoupling, not shown in circuit. pese] See also part 1 figure 16). sg142 Capacitors: C4,C5,C7,C14 = 470 p C6,C13 = 330 p C107...C111=120n (supply line C126...C130= 10n decoupling, not a. sn shown in circuit. É 020,04 w See also part 1 JD to ficiasync. nas * figure 16) o ICs (fa ICB (NO... N12) = 7408 IC9(N13... N16) = 7408 po IC1O (N17,N18,N28,N29) = 7408 E 1CM (NI... N22) = 7408 1C12 (N23,N27,N30,N31) = 7408 1C14 (N32...N35) 432 seis 3 1C15 (N36,N52,N53) = 7432 2 [1 )— IC16 (N37,N38,N39 = 7432 NA VE gi] NIS E IC17 (N40,N41,N42,N45) = 7432 o IC18 (N43,N44/N46,N47) = 7432 | o asa line blanking cera 2 ajm8 hi aa, burst enable ccir tv pattern generator elektor october 1977 — 10-11 tend to obscure the overall picture of the generator, and for the sake of completeness the full circuit is given in figure 7. The sections of the circuit described last month were, of course, mounted on the motherboard described in that article, whereas the circuits discussed this month are mounted on the first of the four modules for which provision is made. The p.c. board and component layout for the module are given in figure 8. In order to avoid the y for an expensive double- , a considerable number of sided p wire links are used on the board, and great care must be taken not to omit any of these. The module may be mounted on the motherboard using wire links or, if the modules are to be removable, IfT/Cannon GO9 series connectors may be used. These are supplied in strips that may be cut to the appro- priate length. The module should be a to field sync. N21 i fine sync. ss Ob - cas ; Ls a [= N20 LA a E OM “o pattern generator DGM 40,+ 05 com 5 Es N23 sus || asus sen 5 line blanking yes Ea sms 6 mounted with the component side of the board facing the component end of the motherboard. Testing Since the circuit is entirely digital the only meaningful way of testing it is to use an oscilloscope to view the wave- forms. Even then, any old “scope” will not do, but an instrument with stable and reliable triggering must be used. Photos 1 to 5 show the waveforms that should be seen. Photos 1 and 2 show respectively the line sync and field equalisation pulses on the lower trace, with the line blanking interval shown on the upper trace as a reference. In each case the signal starts after the 1.5 us front porch of the line blanking interval, but the duration of the line sync is twice that of the equalisation pulse. Photo 3 shows the field sync pulse on the upper trace compared with the line blanking on the lower trace. Here again the pulse starts 1.5 us after the leading edge of the line blanking interval, but the duration of the field sync pulse is much longer than the line blanking interval. Photos 4 and 5 give an overall view of the sync waveform during the field blanking interval. In photo 4 the upper trace shows the 25 H signal, while the lower trace shows a modulated video waveform. At the start of the 25H period the video modulation is sup- pressed. Five equalisation pulses appear, followed by five field sync pulses, followed by a further sequence of five equalisation pulses. The rest of the 25 H period is occupied by line blanking pulses. The lower trace of photo 5 shows an expanded view of the equalisation and field sync pulses during the 7.5H period (upper trace). The difference between field sync and equalisation can clearly be seen, plus the fact that these pulses have only half the spacing of the line blanking pulse at the right of the trace. The next part of this article will discuss the pattern generator module, which will provide a variety of patterns for TV testing. FERRE AAA RARA ARMAR ERRAR oo 10-14 — elektor october 1977 impedance variation detector a edonce | rioion ld ) First of all, a brief recap of the conven- tional method of measuring an unknown resistance. An internal battery in the multimeter causes a small current to flow through the object whose resistance is being measured. The size of this current is inversely proportional to the value of the unknown resistance, which is indicated by the deflection of the meter needle. It is clear that, particularly when measuring high resistances with sensitive instruments, this current is easily affected by external sources of inter- ference such as static electricity, induced voltages etc. Even when the system has been screened against such external interference, there remains such sources of error as ageing of the instrument. The block diagram in figure 1 shows the alternative method of measurement. An LC-oscillator (block 1) produces a constant frequency and amplitude 10 kHz AC-voltage. The stability of the frequency is obtained by choosing a suitable type of oscillator, whilst the amplitude is held constant by an ALC (Automatic Level Control; see block 2). So as not to overtax the ALC, an extra buffer stage is included (see block 3) which has a high internal resistance. The impedance between the measurement electrodes and the internal resistance of the buffer stage together form a voltage divider. This voltage divider is intended not only for the 10 kHz signal, but also for unwanted transients. Since only the divided-down 10 kHz signal is to provide the reference for the measured impedance, it is first pre- amplified by block 4 and then cleaned of any interference by the bandpass filter of block 5. The insertion loss of the filter is compensated for by the succeeding amplifier stage (block 6). All that is now needed to indicate the value of the measured impedance is a suitable detector circuit (block 8), the DC output voltage of which is proportional to the impedance of the measured object. However, since the circuit is intended to register changes in impedance, the detector circuit is followed by a variable gain amplifier stage (block 9) and a voltage controlled oscillator (block 10). In order to measure small changes in high resistance circuits, the use of a simple ohmmeter is not sufficient, since the measurement can be distorted by the effect of voltage transients originating both from the object being measured as well as other sources of interference. These errors can be largely eliminated however, by employing an AC-voltage of a suitable frequency (e.g. 10 kHz) along with a selective filter. This method will measure not only changes in resistance, but will also indicate variations in the AC impedance of a circuit. The detector can be used to indicate changes of the impedance of the human body, of animals or even of plants, which are the result of muscle contractions, changes in mood, external stimulae etc. The frequency of the audible signal produced by the loudspeaker varies with changes in the measured impedance. The automatic gain control (block 7) ensures that the amplitude of the 10 kHz signal remains constant when there is no variation in the measured impedance. It determines the free run- ning frequency of the VCO and thus the pitch of the 'steady state” reference sig- nal. The frequency of this signal was chosen so that even quite small changes in pitch would be clearly audible. The AGC responds relatively slowly, so that gradual changes in impedance are also clearly discernible. When, for example, the impedance of the object being measured increases, the output voltage of the detector rises, causing a change in the pitch of the loudspeaker signal. If the impedance remains at this new level, then the amplitude of the AGC signal at the input of the detector gradually falls back to its original value and the pitch of the loudspeaker signal is the same as it was before the change in impedance. The circuit Figure 2 shows the circuit diagram of the “transmitter' stage of the detector, which contains the LC-oscillator, the ALC and the buffer stage. The LC- oscillator is built round transistor Tl; the resonant circuit consisting of LI, C1, C2, C3 and C4 determines the fre- quency of the oscillator. The positive feedback path runs from the emitter via the capacitive voltage divider C3/C4 to the base of Tl. This type of oscillator is distinguished by its frequency stability. In order to also maintain a constant amplitude, the ALC circuit round T2 was added. If the amplitude of the signal at the collector of T1 increases, T2 is turned on harder, so that the voltage at the base of TI drops, thus causing the amplitude of the oscillator signal to decrease. As a result of the high Q-factor of the LC-resonant circuit, the voltage across C2 is greater than that across the whole circuit. In order not to overload the oscillator and to reduce feedback, a buffer stage round T3 is included. This buffer stage has a high input and output impedance. The high output impedance is necessary in view of the very high impedance of 10-16 — elektor october 1977 subliminal perception tester sulolminol The circuit basically consists of a random number generator linked to two displays. The test person looks at one of the displays whilst the second display is situated outside his field of vision. Shortly after the start button is pressed, the decimal point on the first display lights up briefly, indicating that a number is about to be displayed. This completely random number is displayed for a sufficiently short time as to be imperceptible at a conscious level. The test person can then ascertain whether he has perceived the number sublim- inally by guessing the answer and checking it egainst the second display, which displays the number continuously. Other experiments for which the circuit may be used include a test for telepathic communication and a test for precog- nition. In the telepathy test, the help of another person is required, preferably someone who is felt to have an empathy with the test person. The latter is required to guess the random numbers seen by his partner on the continuous display. In the test for precognition, the idea is to try and guess the numbers before they are displayed, again with the help of a second person who checks the results. The circuit Transistors T2 and T3 in figure 1 form a one-shot pulse generator. When push- button Sl is depressed, T2 turns on causing C4 to charge. Since the collector of T2 is fed with a 100 Hz waveform from the output of the bridge rectifier D1...D4, the collector voltage will vary between O and 25 V, which means that C4 is charged to between approx. 8 and 25 V. This voltage is used to control VCO1 whilst VCO 2 is controlled by T3. The free running frequency of VCO 1 is approx. 1/3 Hz and that of VCO2 approx. 30 kHz. As long as VCO 2 is not blocked by D14 or DIS, its output is fed to IC3, which is connected as a decade counter. As soon as the output of N2 goes low, VCO 2 is blocked by Di4 and flip-flop FF2 causes this condition to be maintained until the start button is pressed once more. The state of the counter is shown on the The ban on subliminal advertising has led to a wider interest in this unusual psychological phenomenon. The following circuit offers the possibility of testing one's response to subliminal messages and may also be used for various other “parapsychological' experiments. perceplion hesheç) second display via IC6. With switch S2 in the open position, the display will not light up until S3 is pressed; if S2 is closed the display will light continu- ously. Gates NS and N6 together form a monostable multivibrator, which triggers IC7 to display the state of the counter on the first display. The display- time is adjustable by means of poten- tiometer Pl. The circuit round the gates N7 and N8 ensures that the decimal point lights up shortly before the random number appears on the display. Since the VCO circuits require a voltage of approx. 15 V, but two TTL ICs are also used, this means that two supply voltages are needed. A suitable supply stage is shown in figure 2. To reduce the dissipation of Tl to a minimum, the second display is fed by an unstabilised voltage. The current-limiting resistors R23...R29 therefore have a higher value than normal. During construction care should be taken to ensure that all COSMOS ICs have a 15 V supply, with the exception of ICS (type 4050) which, like the TTL ICs, should be fed off 5 V. Alternative version With 7-segment displays there is the danger that a “3º or a *O' may be mis- taken for an “8”. This drawback can be avoided by adopting an alternative set of symbols. Figure 3 shows an arrange- ment of LEDs which permits the fol- lowing symbols to be displayed: 1. astar 2. a square 3. a circle 4. across 5. two zig-zag lines If this arrangement is adopted, then the decoder and display circuit must be altered accordingly (see figure 4). The A-, B- and Cinputs of the decoder drivers IC6' and IC7' (type 7445) are connected to the corresponding outputs of the counter (IC3), via the interfacing gates N10... N12. The reduction in the number of symbols means that the counter need only count to 5. This is achieved by connecting D16 to the C | — and not to the D — output of the subliminal perception tester elektor october 1977 — 10-17 q Do 2x 5V 2 HP 5082-7730 o 18M Já 1á pune 6 feser O son Piso nz fas RO, mass No Rãe| ER RE RD a ci Ri6 na E ERP RAE ERES E 7 E: EEE EESC: a), Ic6 6 [| IC7 als 7447 7447 RE no) Nm) Ni) mig El om Z Á | | Ses | O ERZ | [ok 1C2 | a 40130) | cj Lo | LE "H | Figure 1. Circuit diagram of the subliminal e perception tester. Figure 2. Supply stage for the circuit in figure 1. A 0.5 A transformer would be suf- ficient for 7-segment displays, but not for discrete LED-displays. D1...D5 5x 1N4001 a al, pai ED 38397 biorhythm program elektor october 1977 — 10-19 Dioriyiim a) 2) Almost everyone experiences “ups and downs; there are days when nothing seems to go right and you feel devoid of energy or inspiration; then again there are days when everything “clicks! and you could take on the world. Until recently it was assumed that these changes in mood were a purely random occurrence and therefore could not be predicted in advance. However there is a growing interest in the theory which interprets these seemingly haphazard variations in mood as the result of fluc- | tuations in a person's “bioclock”. The originators of the theory, a cer- tain Wilhelm Fliess (1858 - 1928) and | Hermann Swoboda (1873 - 1964), pro- | posed that the way a person feels at any given time is determined by three domi- nant biological cycles. These cycles are the physical, which has a period of 23 days, the emotional, with a period of 28 days, and the intellectual cycle, with a period of 33 days. These cycles can all be represented in the form of a sine- wave, with a positive and a negative half-cycle; the amplitude of the wave- form indicates the intensity of the con- dition represented by the curve, the positive portion of the curve represents a favourable influence and vice-versa. The days on which the curves intersect the zero-crossing point are considered to be particularly critical. The theory further states that all three cycles begin at birth, so that when com- piling a rhythmogram (graph of the three cycles over a period of time) this date is of decisive importance. If the number of days which have elapsed between the date of birth and the cur- rent date are divided by the number of days in a complete cycle, then the remainder represents the stage of that cycle for the day in question. It is thus possible to compile a rhythmogram of a person for a given period of time such as a month or even a whole year. Figure 1 shows an example of a rhyth- mogram; it is that of the former Chanceller of West Germany, Willy Brandt, for the month of May 1974. Brandt was born on the 18th of Dec., 1913; he became Chanceller in 1969, a post which he was forced to quit in May, 1974 when it transpired that one of his most trusted advisers had been working progjfoim This article provides a program for the HP-65 programmable calculator from Hewlett-Packard with which it is possible to determine, and even predict in advance, the state of one's “bioclock” on any given day. Figure 1. Rhythmogram of Willy Brandt for the month of May 1974. Willy Brandt was born on the 18th of December, 1913. asa spy for the East Germans. His rhyth- mogram for that month shows a mark- edly negative tendancy at the point in time of his resignation (arrowed). Such examples could be multiplied almost indefinitely. However, whether they allow any conclusions to be drawn as to the validity of the above theory is a question we leave to our readers to answer. The program Since a large amount of tedious calcu- lation is required to compile a rhyth- mogram, the simplest solution is to use a calculator. A programmable calculator offers the advantage that once the appropriate program has been read in, it is possible to obtain any rhythmogram simply by supplying the relevant dates. Table 1 shows the complete 83-step pro- gram used to determine the start of the various biorhythm cycles. The program functions as follows: the number of days from the Ist of January 1900 to the date of birth (not forgetting leap years) is first calculated, and this num- ber is then subtracted from the number of days between the 3Ist of December 1899 and the date of the day in which we are interested. The result is obvi- ously the age of the person in days plus an extra day to allow for the fact that it is the current and not the previous day for which the program must be calculated. The above number is then divided by the number of days in the physical cycle (23) and the remainder 1/2| 3] 4] 5] 6 7| 8| 9/10/11/12/13/14/15[16/17 | 18] 19/20] 21/22/23/24/25/26/27/28/29/30]31 Pa Ro “4 » E + , 4 Ns é N Pas Elos 9847 | = intellectual cycle E = emotional cycle P = physical cycle 10-20 — elektor october 1977 biorhythm program Table 1. ENTRY | SHOWN COMENTE ENTAY | SHOW comments | | REGISTERS D 14 Fi PER! R uso 1 o catculate days from cix EO s 1-1-1900 to birth date RE DE HANJFEB. sTO1 3301 |Jand storein1 1 | à DES Rz RIN 24 1 01 com ql Es 2 o2 | month 5 12 E 8 calculation Ra D 14 || calculate 31-12-1899 to day of interest 1 o (cont.) RCLI 3401 |calculate days from birth + 8 Lico 51 to date of interest 60 3 92 Ra ENTER 4 o 00 ENTER 41 “| B Re, 6 06 Rs 3 o3 alculate 23-day period x n c 13 f Eai] RS sa INT guie] Re cx E gix=y | 3507 2 02 alculate 28-day period f 3 8 og TE [E JAN/FEB. Rz o E 13 jo 1 o! orrection RS E E g elx E 2 03 Rg 3 03 6 06 gar 3 o3 alculate 33-day period 5 os alcdlation q 13 . ea Rg BIS E 2 bre; cix aa 5 os | É 8 x n LABELS LBL 23 | period calculation t 3 A SiRTHDATE O 13 80 INT E B pare ENTER El enter period + Bi add months C asvramcare. girt 3509 ÇA 8 add days D DAvscaLc. gix= 3507 RIN 24 E 8 fcalculate remainder o 32 1 as 2 E 3 o oo 4 1 o1 5 Ho + ul EM 6 x n 7 BIN 24 8 LBL 23 — |calculate days 9 E) 14 pa 32 | FLAGS srt s1 VAN/FEB 1 JAN/FEB gixey 3507 Jeorrection month 3 o3 calculation 2 glx>y | 3524 so + Ei hoo a Table 1. The complete biorhythm program Table 2. for the HP-65. step | inputdata Lo key | display 1 day of birth ENTER day Table 2. Instruction sequence to input tht Z month of birth ENTER month date of birth and current da: a year of birth A 4 day of interest" ENTER day 5 month of interest! ENTER month 6 vear of interest! B physical cycle 7 R/s emotional cycle 8 R/S intellectual cycle 9 for new case, return to step 1 or step 4 1 the date for which the cycle is being calculated. 
