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The diodes (6x 1n4148) are already in. Transistors & integrated circuits to go.
The main board uses 10 transistors:
One PN4250 & nine PN5179. (my vintage TKB uses nine EN5179s)
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The PN4250 is unchanged from the original.
There are 9 types of ICs used on the main board.
These are:
1. LM324N. We need 4 of these.
Mouser #: 512-LM324N
Manufacturer: Fairchild Semiconductor
This is a quad Operational Amplifier.
2. 4042. We need just one of these
Mouser #: 595-CD4042BE
Mfr. #: CD4042BE
Manufacturer: Texas Instruments
This is a CMOS quad clocked D-type latch.
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For more about latch circuits click here:
http://www.dummies.com/how-to/content/electronics-projects-how-to-build-a-latch-circuit.html
3. 4050. We need 3 of these
Mouser #: 595-CD4050BE
Mfr. #: CD4050BE
Manufacturer: Texas Instruments
This is a non-inverting hex buffer.
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Some info on buffers:
http://hyperphysics.phy-astr.gsu.edu/hbase/electronic/buffer.html
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and connect one of the 8 inputs to the output
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Manufacturer: Texas Instruments
The 4069 contains 6 CMOS inverter circuits.
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This is a Quad 2-Input. AND Gate.
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For more info on Gates click here: LOGIC Gates
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Manufacturer: Texas Instruments
Desc.: Counter ICs Binary Up/Down
Manufacturer: Texas Instruments
Desc.: Counter ICs Dual Binary Up
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The diodes (6x 1n4148) are already in. Transistors & integrated circuits to go.
The main board uses 10 transistors:
One PN4250 & nine PN5179. (my vintage TKB uses nine EN5179s)
This is a pic of a vintage EN5179.
Today the PN5179 and EN5179 are very hard to get, so they have been replaced with the more common 2n3904.
There are 9 types of ICs used on the main board.
These are:
1. LM324N. We need 4 of these.
Mouser #: 512-LM324N
Manufacturer: Fairchild Semiconductor
This is a quad Operational Amplifier.
2. 4042. We need just one of these
Mouser #: 595-CD4042BE
Mfr. #: CD4042BE
Manufacturer: Texas Instruments
This is a CMOS quad clocked D-type latch.
http://www.dummies.com/how-to/content/electronics-projects-how-to-build-a-latch-circuit.html
3. 4050. We need 3 of these
Mouser #: 595-CD4050BE
Mfr. #: CD4050BE
Manufacturer: Texas Instruments
This is a non-inverting hex buffer.
http://hyperphysics.phy-astr.gsu.edu/hbase/electronic/buffer.html
4 4051. We need 3 of these.
Mouser #: 595-CD4051BE
Mfr. #: CD4051BE
Manufacturer: Texas Instrumen The CD4051B is a single 8-Channel multiplexer having three
binary control inputs, A, B, and C, and an inhibit input. The
three binary signals select 1 of 8 channels to be turned on,
5. 4069 - We need two of these.
Mouser #: 595-CD4069UBE
Mfr. #: CD4069UBEManufacturer: Texas Instruments
The 4069 contains 6 CMOS inverter circuits.
For more info click here:LOGIC INVERTERS
6. 4081 - We need two of these.
Mouser #: 595-CD4081BE
Mfr. #: CD4081BE
Manufacturer: Texas InstrumentsThis is a Quad 2-Input. AND Gate.
7. 4516 - just one is needed.
Mouser #: 595-CD4516BE
Mfr. #: CD4516BEManufacturer: Texas Instruments
Desc.: Counter ICs Binary Up/Down
8. 4520 - We need just one.
Mouser #: 595-CD4520BE
Mfr. #: CD4520BEManufacturer: Texas Instruments
Desc.: Counter ICs Dual Binary Up
9. MM74C150
This is a 16 line to 1 line Multiplexer
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