Velleman K1803 User manual

K1803
ILLUSTRATED ASSEMBLY MANUAL H1803IP'2
T ot al sold e r poi n ts: 29
Difficulty level: beginner 1 2 3 4 5 advanced
Thiskithasbeendevelopedaspre-modulefor
anumberofaudioapplicationswherethereis
insufficientinputsignal.Applicationsasa
microphonepre-amplifierorforlevelcorrection.
UNIVERSAL MONO PREAMPLIFIER
Specifications
 Power supply: 10-30VDC / 10mA.
 Output impedance: 1Kohm.
 Adjustable output level: max. 40dB.
 Frequency range: 20Hz to 20kHz ± 3dB.
 Max. input signal: 40mV.
 PCB dimensions: 30 x 40mm (1.2" x 1.57").

VELLEMAN NV
Legen Heirweg 33
9890 Gavere
Belgium Europe
www.ve llem an.be
www.velleman-kit.com

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Assembly hints
1. Assembly (Skipping this can lead to troubles ! )
Ok, so we have your attention. These hints will help you to make this project successful. Read them carefully.
1.1 Make sure you have the right tools:
• A good quality soldering iron (25-40W) with a small tip.
• Wipe it oft en on a wet s p onge or cl oth, t o k ee p it cl ean; th en ap ply sol de r t o t he ti p, t o gi ve it a wet look . Th is is c al le d ‘thinning’ and will
protect the tip, and enables you to make good connections. When solder rolls off the tip, it needs cleaning.
• Thin raisin-core solder. Do not use any flux or grease.
• A diagonal cutter to trim excess wires. To avoid injury when cutting excess leads, hold the lead so they
cannot fly towards the eyes.
• Needle nose pliers, for bending leads, or to hold components in place.
• Small blade and Phillips screwdrivers. A basic range is fine.
For some projects, a basic multi-meter is required, or might be handy
1.2 Assembly Hints :
⇒Make sure the skill level matches your experience, to avoid disappointments.
⇒Follow the instructions carefully. Read and understand the entire step before you perform each operation.
⇒Perform the assembly in the correct order as stated in this manual
⇒Position all parts on the PCB (Printed Circuit Board) as shown on the drawings.
⇒Values on the circuit diagram are subject to changes.
⇒Values in this assembly guide are correct*
⇒Use the check-boxes to mark your progress.
⇒Please read the included information on safety and customer service
* Typographical inaccuracies excluded. Always look for possible last minute manual updates, indicated as ‘NOTE’ on a separate leaflet.
0.
0
0
0

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Assembly hints
1.3 Soldering Hints :
1- Mount the component against the PCB surface and carefully solder the leads
2- Make sure the solder joints are cone-shaped and shiny
3- Trim excess leads as close as possible to the solder joint
REMOVE THEM FROM THE TAPE ONE AT A TIME !
You will find the colour code for the resistances on our website: www.velleman.be
DO NOT BLINDLY FOLLOW THE ORDER OF THE
COMPONENTS ONTO THE TAPE. ALWAYS CHECK
THEIR VALUE ON THE PARTS LIST!

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 R1 : 100K (1 - 0 - 4 - B)
 R2 : 100K (1 - 0 - 4 - B)
 R3 : 100K (1 - 0 - 4 - B)
 R4 : 100K (1 - 0 - 4 - B)
1. Resistors
R...
 IC1 : 8p
2. IC socket, Watch the po-
sition of the notch!
 AF IN (2 x)
 AF OUT (2x)
 Power (+)
 Power (-)
4. PCB pins
Constructi o n
 RV1 : 220K (250K)
6. Trim potentiometer
RV.. .
 C1 : 10µF
 C2 : 10µF
 C3 : 10µF
 C4 : 10µF
 C5 : 10µF
5. Electrolytic capacitors.
Watch the polarity !
C...
 IC1 : LM358
 Pay attention
to the
position of
the notch!
7. IC mounting
 R5 : 100K (1 - 0 - 4 - B)
 R6 : 100K (1 - 0 - 4 - B)
 R7 : 2K2 (2 - 2 - 2 - B)
3. Vertical resistors
R...

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8. Connection
Conne c tion
 Connect a stabilized supply between 10 and 30V with the points “+” and “-” on the print.
 The input is connected on the points “AF IN”.
 The output is taken on the connection “AF OUT” and the ground “-”.
 To connect your in– and output you’d better use a screened wire, this to avoid interferences and rumble
 With the trimmer RV1 you can control the output signal between 0 and max.
Connec tion e xa mple
Dyna mic mi crop hone
Telephone pick up coil
...
MAX. 40mV
To : Amplifier, Mixing
panel, Tape recorder, ...
10 ... 30VDC
INPUT
OUTPUT

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9. Schematic diagram.
Schematic diagram & PCB
R4
100K
R3
100K
R2
100K
C1
10µ
GND
+V
C2
10µ
C5
10µ
SK1
AF IN
SK2
AF OUT
3
2
84
1
IC1A
5
6
7
IC1B
C3
10µ
C4
10µ
R7
2K2
R6
100K
R1
100K
R5
100K
RV1
220K
10. PCB

Modifications and typographical errors reserved
© Vellema n nv.
H1803IP - 2010 - ed.2
VELLEMAN NV
Legen Heirweg 33, 9890 Gavere
Belgium - Europe
5 410329 434977