IF YOU HAVE A RUNNY NOSE...In this case doctors usually recommend to warm up the area of nose and the bridge of the nose with bags of hot sand or a medical reflector. But here’s the problem: the bag has to hold hands and to periodically change the sand cooled and the heat from the reflector heats not only the nose but the whole face, and even the light from the lamp is blinding. Heating pads, too uncomfortable — too big. But perhaps the most significant drawback of all mentioned devices is the inability to smoothly adjust the heating temperature.

Electronograms thermostat that we offer to attention of readers, specifically designed to warm up the area of nose and the bridge of the nose. The device is powered by a step-down transformer from the mains AC voltage of 220 V. the Maximum power consumption does not exceed 30 watts.
The temperature of heating is infinitely adjustable and does not exceed 60°. Heating elements metal film resistors. The thermostat is a thyristor device with pulse-phase control (Fig 1). Changing the time of the unlocking regulating thyristor V5 with respect to the transition of the voltage at its anode through 0, we thereby change the conduction time of V5 during the period of the voltage rectified by the diodes V1—V4. This changes the energy supplied to the heater, assembled on the resistors R1—R7, and hence the heating temperature.
The shaper control pulses for the thyristor is made on the basis of analogue odnoimennogo transistor on a semiconductor triode V7, V8. Since the beginning of the period while the capacitor C3 is charged to a threshold voltage substantially equal to the voltage drop across the resistor R15, the transistor V7, V8 are closed, the thyristor is closed and V5.
After charging C3 to the threshold voltage V7, V8 is opened, and on managing the transition of V5 receives a control pulse, the Thyristor is unlocked and remains open until the moment of transition of voltage on its anode via 0.
Fig. 1. Scheme elektromotoren with the thermostat.
Fig. 1. Scheme elektromotoren with thermostat.
Fig. 2. Heater.
Fig. 2. Heater.
Fig. 3. The circuit Board of the thermostat with the layout of the parts.
Fig. 3. The circuit Board of the thermostat with the layout of the parts.
The charge time of capacitor C3 and thus the closed state of the thyristor V5 depends on the value of the variable resistor R9. Therefore, rotating the handle R9, it is possible to vary the charge time of capacitor C3 to the threshold voltage. And this leads to change of conduction time of thyristor V5 and therefore the power supplied and the heater.
As the pulse controller having interference, the device includes a filter C1, L1, L2, prevents the penetration of interference in the network.
The design uses the following details: R9 — variable resistor SPO-0,5, R8 — permanent MLT-1, rest — sun-0,125 or MLT-0,25. Capacitors: C1 — MBM 750, S2 — BM-2 to 200, C3 — MBM 160, H1 — incandescent 6.3 X 0,22 MN.
Inductors L1 and L2 have a pot-core of ferrite Б26 brand М2000НМ and contain 110 turns of wire PEV-2 0,31. They can be replaced with circular ferrite rods М400НН Ø 8 mm, length 25 mm. the Transformer T1 is made on the yoke Ш20Х25. The winding of I contains 2500 turns of wire sew-2 0,23, winding II has 295 turns of PEV-2 of 0.67.
Д242 diodes can be replaced by КД202А, КД202В, КД202Д, КД202Ж, КД202М, КД202Р or Д242Б. КУ202Е is possible to use thyristors КУ202И, КУ202Л or КУ202Н. Transistor МП114 permissible to replace MP 115, КТ203А or КТ203Б and КТ315В — КТ315А, КТ315Г, КТ315Д.
For the heater cut out from a sheet of copper with a thickness 0.4—0.8 mm of the two shapes in figure 2 and solder the resistors between OMLT-2. Then to the two conductive plates to connect the two wire mgshv 0.75 mm length 1.5—2 m for connecting the heater to the thermostat.
Fig. 4. The design of the thermostat
Fig. 4. Design of a controller:
1 — upper front, 2 — screw M5 X 25, 3 — lamp receptacle, 4 — housing, 5 — circuit Board, 6 — nut M5, 7 — nut M6, 8— lower 9 — screw M3.

Fig. 5. Stand
Fig. 5. Strut:
a — upper, b — lower.

Next curly copper strips with the resistors Flex the shape of the nose, wrap three layers of fiberglass cloth and panel. To the corners of the heater, attach a ribbon or rubber tape width 10 — 30 mm for fixation of the heater face.
On the front panel of the thermostat, made of transparent Plexiglas mounted socket for connection of the heater displays the temperature control knob (R9) and drilled the window under the lamp H1. Inscriptions in ink on the sheet of paper which is fixed on the back side of the front panel.
Installation of the electronic unit is made on a printed circuit Board made from glass fiber plastic with thickness of 1.5 mm (Fig. 3).
The thermostat is assembled in a plastic case with internal dimensions 187X82X52 mm (Fig. 4). Printed circuit Board is secured using M3 studs and struts (Fig. 5).
Use electronograms very simple. The thermostat included in the network it is connected to the heater and fix it to the nose area. Rotating the knob “Temperature”, choose the desired degree of heating. However, before you start to use made electronograms, be sure to consult your doctor.
A. RUBANOV, Stavropol

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