Summary of UKW
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Imprint © 2011 franzis verlag gmbh, 85586 poing www.Franzis.De author: burkhard kainka art & design, composition: www.Ideehoch2.De isbn 978-3-645-10057-1 produced on the order of conrad electronic se, klaus-conrad-straße 1, d92240 hirschau all rights reserved, including the rights of photo-mechanica...
Page 3: Ukw Retro Radio
Ukw retro radio the ukw retro radio 4 components 5 installation of control elements 6 soldering 8 first test and settings 12 reception practice 13 explanations on the circuit diagram 13 3.
Page 4: The Ukw Retro Radio
4 the ukw retro radio this state-of-the-art vhf radio with traditional design receives fm stations in the range of 87.5 mhz to 108 mhz with good reception performance. You will mainly hear the strong local stations with good sound. However, the receiver is sensitive enough to also receive remote sta...
Page 5: Components
D1 varactor diode 1sv101 r1 4.7 k o (yellow, violet, red) r2 220 k o (red, red, yellow) r3 1 k o (brown, black, red) r5 330 k o (orange, orange, yellow) r6 33 o (orange, orange, black) c15 elko 100 µf c17 100 nf ceramic (104) 5 with the highly integrated receiver ic tda7088, construction of a dedica...
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Assembly of the control elements the radio has two rotary controls. One for frequency and one for volume. The volume controller with three connections additionally also carries the on/off switch with two connections. If you turn the axis all the way to the left, the switch opens. Place the volume co...
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Speaker screw the solder eye to the base of the telescopic aerial. Then push the aerial through the casing opening from the inside and push the end into the flat holder, which you have to attach properly in the casing with the included adhesive tape. The aerial is then installed sufficiently firmly, bu...
Page 8: Soldering
Soldering the pcb already contains many soldered-on smd components (surface-mounted device): the receiver ic tda7088, 15 capacitors and one resistor. Only a few of these components still must be soldered in with connection wires. This includes all components of the nf amplifier, the coils and compone...
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Both coils must be made of the included equipment wire. Each of them has three turns with an inner diameter of 5 mm and a length of approx. 7 mm. Use the 100-µf-elko as a coiling mandrel. First wind three turns close to each other. Then draw the turns apart so that the coil has a total length of app...
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The varactor diode d1 now solder in the electrolyte capacitator c15 (100 µf). Observe installation direc- tion. The plus pole is marked on the pcb. The minus pole is marked with a white dash. It points towards the ic. Then install the ceramics of the capacitator c17 with 100 nf (print: 104). The ins...
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The pcb completely equipped next, solder on the matching wire pieces for the two potis. For their lengths, see the wiring plan. Either push the wire ends through the holes and solder them on like the remaining components, or solder them to the solder areas flat. The pcb should be installed suspended ...
Page 12: First Test and Settings
The complete wiring the radio is now assembled completely and can be tested. Draw the set-up with your name and date in the circuit diagram on the last page of these instructions. Then copy or tear out the page and glue it into the radio casing. This will make it possible to understand everything ev...
Page 13: Reception Practice
For fine tuning, push a screwdriver between two turns to bend them apart a lit- tle. When the lower band threshold is perfectly adjusted, you can also adjust the upper threshold of 108 mhz. The frequency depends on battery voltage, how- ever. If you find in current operation that the upper-most statio...
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And the higher the reception frequency. The only tuning point is coil l1 to set the lower threshold of the oscillator frequency. The low frequency end stage is a simple class-a amplifier with the two transistors t1 and t2. Quiescent current is approx. 20 ma. The circuit still works at a good sound as...
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