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| Electronic Project Kits |
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RIAA EQUALIZED PREAMPLIFIER
STEREO KIT The groves in phonograph records could not handle the deep bass and high treble in live music. The industry developed a standard recording curve and the missing sounds were compensated for by circuitry in playback preamplifiers. The R.I.A.A. (Recording Industry Association of America) set the standard for the “RIAA curve”. Today amplifiers are designed for flat response and they make old phonograph recordings sound very flat. Using an RIAA preamplifier compensates for todays flat amplifiers exatly as the old phonographs were able to do. The kit duplicates the RIAA curve accurately; at a kit price. Operation on 9 to 12 V. DC. 80-007 ................................. $11.95 |
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STAIRWAY TO HEAVEN GAME Pressing the switch while a dual LED is green advances you to the next stage; but mess-up and press while red, and you go back to the beginning. It can be tricky and a challenge. Fun and teaches basic electronics. Operates on 9V battery. 80-005 ................................. $15.95 |
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THREE DIGIT COUNTER MODULE An event counter; this economical counter module may be ganged for six or nine digits. Has count and reset switches with debounce built-in. Operates on a nine volt battery. This is a two board kit with the count and reset switches along with the debounce circuitry on one board, the LED digits and circuit on another. 80-010 ................................. $24.95 |
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LED DICE WITH
SLOW-DOWN This is an excellent kit for use as an introduction to electronics and circuit analysis. Seven LED’s arranged like a real die face. Push the switch and the dice rolls and then slows down and then stops. Uses an ingenious circuit design to minimize parts count. Uses a 555 and 14017 integrated circuits. Includes plastic case; battery operation. 80-030 ................................. $12.95 |
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LCD TEMPERATURE METER (Celsius Only) Designed around a single IC, the Harris No. 7106, is this temperature meter with excellent accuracy. All parts needed, even a case, are included except nine volt transistor battery. Instructions also explain how to use the kit to make a volt or an amp meter in various ranges. The circuit board has room for additional components if you use it to make a digital panel meter. 80-020 ................................. $32.95 |
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INFRARED BEAM DOOR MINDER A transmitter sends an I/R beam up to 75 feet to a reciever (on separate pc board); breaks the beam and a relay is tripped. Use the relay to control a bell or light or other device; even a video recorder and camera. Operation requires 9 to 12VDC, a wall adaptor is fine and you may want two units (provision is made to power both boards with one supply via a two conductor wire). Use to watch hallway or drive way, across the doors to a three or four car garage etc. and we know of a photographer taking wildlife photos this way. The uses for alarms, photography, door minding and so on are numerous. You could make weatherproof hoods to use out-of-doors but be sure to protect from moisture. 80-013 ................................. $22.95 |
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R.F. AMPLIFER KIT A small circuit, using the Mar-6 Amplifier IC, this kit will provide as much as 20 db gain. Connect at receiving antenna input; will boost signals from 1 mhz to 1000mHz; two RF amplifier kits may be cascaded for use at low, broadcast-band frequencies. Use with Scanners, Ham recievers, SWL reciever etc. You could add a metal case and RF connectors for permanent use. May be used to boost signal for scope or frequency counter as well. 80-045 ................................. $17.95 |
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INTRODUCTION TO
A POWER SUPPLY (Practical hobbyist power supply) A practical battery eliminator for circuit projects at the bench. This is a basic power supply using two IC’s (7805) regulators. User needs to supply a transformer up to 20V AC for input (see page 114). Outputs are regulated, one variable and one constant 5V DC. A good introduction to power supplies. 80-040 ................................. $16.95 |
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PC BOARD MOUNTED
RELAY The output of many circuits have an alarm signal which must be connected to a remote switching device. Or, sometimes you will have a kit to test which needs a relay connected to it. For this purpose, this kit is perfect. A 12 volt (coil) relay mounts on a PC board which includes a protective diode and terminal blocks. The terminal blocks make for fast, easy screw-connection of wires to coil and to the contacts. If you prefer a different relay coil voltage, the boards are available separately. Board accommodates any Philmore relay from 3V to 24V coils (all ten amp contacts). See index for relay page. Relay kit with 12V, 10 amp relay, PC board and hardware. 80-043 ................................... $9.95 Blank boards, Package of two. 12-605 ................................... $3.95 |
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44 WATT STEREO
POWER AMPLIFIER The circuit is a gem; a TDA1554 IC is the heart of an amplifier that will output 22 watts per channel with excellent sound quality. (Typical THD less then 0.1%!). Originally intended for automobile use, but can be used as a home amplifer if you have a good power supply. Operates on 13 to 14.4 volts (typical automobile voltages with engine on) and can draw as much as five amps at 13.8V DC. 80-050 ................................. $29.95 |