Vacuum Tube / Valve Pre-Amp Build and Test.

This is Part 2, in part 1 (https://youtu.be/4iXPnBG9hhQ) We compared a Semiconductor JFET circuit with a Vacuum Tube circuit. In part 2 we build the Vacuum Tube Audio Pre-amp and test it.

Schematic Download: https://www.paay.us/Downloads/DIYTubeAmp.zip

Tube Amplifier Kit: https://www.aliexpress.com/item/3256805088058259.html

Lab Equipment used:
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Rigol Oscilloscope: https://www.amazon.com/gp/product/B08VDXT4TM
UNI-T UTG932E UTG962E Function/Arbitrary Waveform Generator: https://www.aliexpress.us/item/2255800929475017.html
ATTEN ST-1509/9150 Soldering Station: https://www.aliexpress.com/item/3256803474681871.html
DIY T12 Soldering Station kit: https://www.aliexpress.us/item/2251832603772229.html
Leaded Solder (One of the few/only good quality Leaded Chinese Solders): https://www.aliexpress.us/item/3256803083306632.html or https://www.amazon.com/gp/product/B07FM4V9F9
UNI-T UT210E Mini Digital AC DC Current/Voltage Clamp Meter: https://www.aliexpress.us/item/2255801052133453.html
BK Precision 390A Multi-meter: https://www.zoro.com/bk-precision-digital-multimeter-750-max-ac-volts-1-000-max-dc-volts-10-max-ac-amps-20-max-dc-amps-390a/i/G8650004/
5-50mm Zoom Lens for Camera: https://www.aliexpress.us/item/3256802106060953.html
Webcam Mokose: https://www.amazon.com/gp/product/B08QJQ4V45
AverMedia 2 Plus: https://www.amazon.com/gp/product/B0763TFZWT
Papeaso Video Capture Cards, 4K HDMI to USB 3.0: https://www.amazon.com/gp/product/B091NWB4RJ
4K@60Hz HDMI 2.0 Video Switcher Selector, Dolby Vision/Atmos Auto-Switching HDCP 2.2 HDR 10: https://www.amazon.com/gp/product/B083NWKPXW
Articulated Camera Arm*: https://www.aliexpress.us/item/3256804042762181.html
Insta360 Link 4K Webcam with AI Tracking and Noise Canceling Microphones: https://www.amazon.com/dp/B0B826KS4B
Wireless Lavalier Microphone USB-C, 2 microphones with noise canceling: https://www.amazon.com/dp/B0CZDJR5QV

Chapters:
0:00 Intro
2:17 Edited Schematic
08:04 Building the Kit.
9:53 Mounting the LEDs.
13:26 Mounting Tube/Valve Sockets.
16:44 Mounting small 1uF capacitors.
19:11 Mounting Resistors.
25:52 Mounting Diodes.
29:02 Mounting Transistors.
34:30 Mounting Electrolytic Capacitors.
37:24 Mounting Barrel Jack.
40:39 Mounting Potentiometer.
42:05 Mounting RCA input/output Jacks.
43:31 Testing the Amplifier.
45:10 Checking Circuit Voltages.
46:57 Testing with a signal generator.
49:45 Testing with a dynamic microphone as input.