Voltase hobby: portable

Showing posts with label portable. Show all posts

Wednesday, September 17, 2014

Portable CD Player Adapter For Car

Whenever Im in the car listening to my favourite CD, it always happens; my batteries go dead. To solve that problem, I built this extremely simple regulator circuit. It steps down the 12V from the lighter socket to 9V which is used by the CD player. Different CD players (I have a Sony Discman) may require different voltages, so just use the correct regulator. All the 78xx series regulators have the same pin out, so the circuit is universal.

Portable CD Player Adapter For Car Circuit daigram

Parts List

Part       Total Qty.                     Description

C1            1                        1000uF 25V Electrolytic Capacitor
C2                      1              10uF 25V Electrolytic Capacitor
C3            1                        1uF 15V Elextrolytic Capacitor
C4                      1                        0.1uF 15V Electrolytic Capacitor
U1        1                        7809 Or Other Regulator (See "Notes")    See Notes
MISC      1                        Cigarette Lighter Plug, Plug For CD Player (See "Notes"),      Heat Sink For U1, Wire, Case.

Notes

The voltage your CD player needs will determine which regulator you use. For 9V, use the 7809. For 6V, use the 7806. For the unlikely 5V use the 7805. Remember that whatever regulator you use, you will need to heat sink it. The metal case or metal cover on the case makes a great heat sink.
I built the circuit in a small case with the long wire to the cigarette lighter plug coming out one end, then another, slightly shorter wire going out the other end to the CD player.

Triple check your wiring. You would hate to ruin an expensive CD player because you reversed one of the connections or hooked the regulator up backwards.

Monday, September 8, 2014

AM and FM Radio with LA1800 Portable

This portable AM and FM radio schema is designed using the LA1800 IC and some other external components. As you can see in this schema diagram the LA1800 manufactured by Sanyo Semiconductors , require few additional components. The LA1800 am FM portable radio schema needs to be powered from a 3 volt DC power supply schema.

AM and FM Radio with LA1800 Portable Circuit Diagram

You can use an 3 volt battery. This radio receiver schema has a low current dissipation of 5.6mA for FM band and 3.2mA for AM band .Also the output signal is driven into earphone speakers , but you can use an additional speaker ( in that case you need to connect an additional small power audio amplifier).

Thursday, September 4, 2014

Mini Portable Guitar Amplifier

Guitar Circuit description:

This small amplifier was intended to be used in conjunction with an electric guitar to do some low power monitoring, mainly for practice, either via an incorporated small loudspeaker or headphones. The complete circuit, loudspeaker, batteries, input and output jacks can be encased in a small box having the dimensions of a packet of cigarettes, or it could be fitted also into a real packet of cigarettes like some ready-made units available on the market. This design can be used in three different ways: Loudspeaker amplifier: when powered by a 9V alkaline battery it can deliver about 1.5W peak output power to the incorporated loudspeaker. Headphone amplifier or low power loudspeaker amplifier: when powered by a 3V battery (2x1.5V cells) it can drive any headphone set type at a satisfactory output power level or deliver to the incorporated loudspeaker about 60mW of output power. This configuration is useful for saving battery costs. Fuzz-box: when powered by a 3V battery (2x1.5V cells) and having its output connected to a guitar amplifier input the circuit will behave as a good Fuzz-box, showing an output square wave with marked rounded corners, typical of valve-circuits output when driven into saturation.

Guitar amplifier circuit diagram:

Guitar amplifier partlist:

R1__________22K 1/4W Resistor
C1__________10µF 25V Electrolytic Capacitor
C2__________100nF 63V Polyester or Ceramic Capacitor
C3__________220µF 25V Electrolytic Capacitor
IC1_________TDA7052 Audio power amplifier IC
J1,J2_______6.3mm Stereo Jack sockets (switched)
SPKR_______8 Ohm Loudspeaker (See Notes)
B1_________9V PP3 Battery or 3V Battery (2 x 1.5V AA, AAA Cells in series etc.)
Clip for PP3 Battery or socket for 2 x 1.5V AA or AAA Cells

Technical data:

Max output power: 1.5W @ 9V supply - 8 Ohm load; 60mW @ 3V supply - 8 Ohm load
Frequency response: Flat from 20Hz to 20kHz
Total harmonic distortion @ 100mW output: 0.2%
Max input voltage @ 3V supply: 8mV RMS
Minimum input voltage for Fuzz-box operation: 18mV RMS @ 3V supply
Current consumption @ 400mW and 9V supply: 200mA
Current consumption @ 250mW and 9V supply: 150mA
Current consumption @ 60mW and 3V supply: 80mA
Quiescent current consumption: 6mA @ 9V, 4mA @ 3V supply
Fuzz-box current consumption: 3mA @ 3V supply

Wednesday, September 3, 2014

Portable Solar Lantern

This portable solar lantern schema uses 6 volt/5 watt solar panels are now widely available. With the help of such a photo-voltaic panel we can construct an economical, simple but efficient and truly portable solar lantern unit. Next important component required is a high power (1watt) white LED module.

When solar panel is well exposed to sunlight, about 9 volt dc available from the panel can be used to recharge a 4.8 volt /600 mAh rated Ni-Cd battery pack. Here red LED (D2) functions as a charging process indicator with the help of resistor R1. Resistor R2 regulates the charging current flow to near 150mA.

Solar Lantern Circuit Schematic

Assuming a 4-5 hour sunlit day, the solar panel (150mA current set by the charge controller resistor R2) will pump about 600 – 750 mAh into the battery pack. When power switch S1 is turned on, dc supply from the Ni-Cd battery pack is extended to the white LED (D3). Resistor R3 determines the LED current. Capacitor C1 works as a buffer.

Note: After construction, slightly change the values of R1,R2 and R3 up/down by trial&error method, if necessary.