Like many of our hosts, Matthew is an aficionado of vintage technology. In this project, Matthew is completely rebuilding a Califone 1400 series portable phonograph from the early 1980s to improve its playback quality. The first obstacle he has to overcome is rebuilding the preamplifier circuit to bring the raw phono signals from the tonearm up to RIAA line level, but he's having a little trouble with the op-amp chip. How hard could it be to build a simple preamp from scratch?
Supplemental Content:
Bill of Materials
| Product Name | Manufacturer | Quantity | Buy Kit |
|---|---|---|---|
| NE5532AP OP AMP, DUAL LOW NOISE, 5532, DIP8 | TI | 1 | Buy Now |
| WAU12-1000 AC/AC Power Supply, External Plug In, Fixed, 1 Output, 120 VAC, 12 W, 12 VAC, 1 A | Triad Magnetics | 1 | Buy Now |
| 1N4002+ Standard Recovery Diode, 100 V, 1 A, Single, 1.1 V, 30 A | MULTICOMP PRO | 2 | Buy Now |
| MCF 0.25W 100R Through Hole Resistor, 100 ohm, MCF Series, 250 mW, ± 5%, Axial Leaded, 250 V | MULTICOMP PRO | 2 | Buy Now |
| ECA-1CM101B Electrolytic Capacitor, 100 µF, 16 V, ± 20%, Radial Leaded, 2000 hours @ 85°C, Polar | Panasonic | 2 | Buy Now |
Top Comments
Very entertaining.
That said, there are a lot of issues to building a GOOD audio amplifier.
Also, your power lines must be very clean or they will introduce unwanted noise into the audio.
I think you have…