I have received several requests for a class in Amplifier Design. The course will cover basics circuit topologies and introduce how component values are determined. For those interested in doing complete designs a second level course will get into the rather simple mathematics of fine tuning circuit values, choosing voltage and current levels and specifying transformers and other components.
I am looking to enroll 12 students at $90 each for 10 lessons listed below. Hoping to start in late February. Test equipment is suggested for those who want to measure things but not at all necessary for the student who just wants to learn how these things work. If you do plan to build something a voltmeter will suffice and you can judge your results with your ears.
Enroll by sending me a personal message here and I will send payment instructions by Paypal, credit card or check. When I get 12 students we will start. Class will be held on Google Hangouts. You will view and hear me and there will be opportunities to ask questions during the lecture by typing them into the chat.
After the lecture I would like to try a discussion period among the participants which I will monitor and attempt to keep on track. The discussion will be about circuits and not about this or that brand of capacitor or wire or resistor.
If you have questions or suggestions about the course outline please ask them on this post. Be sure to vote on what you want.Lectures and equipment suggestions
10 Lectures on tube amp design
1. Review ohms law, Thevenin’s theorem, volts, amps, watts, impedance, AC peak and RMS relationship to DC values
2. How to set up and bias a basic gain stage. Multi stage amplifiers.
3. Stage gain, input and output impedance, output voltage and current
4. Typical gain stage applications : common cathode, cathode follower, balanced,White follower
5. Line amps, phono RIAA EQ, MC/MM preamps
6. Power supplies: Choke input, capacitor input, hum reduction techniques
7. Intro to power amps: Push pull, single ended, OTL, SEPP, Ultralinear, Triode, Class A, Class AB1 and AB2
8. Power tube characteristics: Pentodes, tetrodes, triodes
9. Feedback: Effects on distortion, Frequency response, Damping Factor, Noise
10. Construction tips, Parts selection, transformer selection and ratings
1 hour to 1:15
10 Saturdays, 11 AM Pacific Time, so that you can try things out that same afternoon.
Suggested Test Equipment for the Experimenter, available on Ebay at low cost. HP is a bargain these days. Heathkit or Eico is less expensive but not as good or as stable.
Digital Voltmeter Fluke 70 series are very nice. Typical $35-50 used
Signal Generator HP 200 tube (Be careful of stiff turning dial, will need skillful lubrication) or later 204 solid state with large frequency dial are very accurate. $35-70
Oscilloscope dual trace, triggered sweep prefered, single trace ok. $50-$200. Hitachi V-152 or V-203 are great scopes, simple layout. Tektronix 422 (under $100) or 453 (under $200) great scopes though harder to fix if there is a problem. Get one that is guaranteed to work.
This is a great scope, looks like it was made by Hitachihttp://www.ebay.com/itm/BK-Precision-10-MHZ-Oscilloscope-1476A-/290839139744?pt=BI_Oscilloscopes&hash=item43b75d15a0
Stay away from the older black BK scopes, they are horrible.