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Nota Bene: The two boards I assembled were bought the last time these were available. The newly available batch may not have the same issues.
One kit was missing a 103 cap. (Stuff happens.)
The circuit board mask calls out a 100uF electrolytic (C5) on the positive supply rail but parts list & parts in kits were 220uF - not a problem, per se.
However, the parts list called out 16v for C5 but my kits contained 10v. There can be a problem there. All Electronics ad says usable supply is 12 - 15 volts & kit instructions cite a 12v supply. A reversed-polarity protection diode (D1) drops the supply voltage a little (~.7 v) off the postive supply input but with a 12v supply that's skating C5 on thin ice for an electrolytic of only 10 working volts. You can see why parts list called for 16v. I replaced the kit cap with a 220uF 35v cap.
Harris & Intersil 8038 data sheets say typical single-ended Vcc supply minimum is 10v. I tried 9v & 18v & both worked w/only differing output levels. TRI & SIN wave amplitudes are well below the SQU wave output (that's a chip feature).
The chip has Hi-Z outputs & will NOT drive any sort of load like a speaker. Even a 10K ohm resistor pulled down the output amplitudes & distorted the sine wave.
25 + | $1.91 each |
100 + | $1.80 each |
10 + | $2.00 module |
50 + | $1.75 module |
10 + | $2.53 each |
100 + | $2.10 each |
10 + | $1.25 each |