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DonaldStott · 27th Apr 2019, 5:39 pm

O.k. all wired up and double/triple checked my connections.

Something not quite right as I'm getting 8.5 - 8.6kHz on the Output from Pin 4 (2Y) of the CD4081 (actually a CD4081BE but I'm assuming the Pins are the same?)

Inputs on the CD4081 are as follows: -

Pin 1 (1A) from Pin 3 (Q13) of the 74HC4060 - 300Hz

Pin 2 (1B) from Pin 2 (Q12) of the 74HC4060 - 600Hz

Pin 6 (2B) from Pin 1 (Q11) of the 74HC4060 - 1,200Hz

Pin 3 (1Y) is connected to Pin 5 (2A) on the CD4081.

Pins 7 (Vss), 8 (3A), 9 (3B), 12 (4A) and 13 (4B) all go to -ve GRND.

Pin 14 (Vdd) goes to +ve 4.5V - only thing I haven't done is to connect a 100pF ceramic capacitor from this power supply Pin to ground?

27th Apr 2019, 5:39 pm	#84
DonaldStott Octode Join Date: Aug 2015 Location: Glasgow, UK. Posts: 1,842	Re: Turntable Stroboscope O.k. all wired up and double/triple checked my connections. Something not quite right as I'm getting 8.5 - 8.6kHz on the Output from Pin 4 (2Y) of the CD4081 (actually a CD4081BE but I'm assuming the Pins are the same?) Inputs on the CD4081 are as follows: - Pin 1 (1A) from Pin 3 (Q13) of the 74HC4060 - 300Hz Pin 2 (1B) from Pin 2 (Q12) of the 74HC4060 - 600Hz Pin 6 (2B) from Pin 1 (Q11) of the 74HC4060 - 1,200Hz Pin 3 (1Y) is connected to Pin 5 (2A) on the CD4081. Pins 7 (Vss), 8 (3A), 9 (3B), 12 (4A) and 13 (4B) all go to -ve GRND. Pin 14 (Vdd) goes to +ve 4.5V - only thing I haven't done is to connect a 100pF ceramic capacitor from this power supply Pin to ground? __________________ BVWS Member Last edited by DonaldStott; 27th Apr 2019 at 5:48 pm.