Mine is triode, but I don't know the feedback details. I plan to measure at several frequencies anyway. And frequency sweep to discover the bandwidth, but not at high power. Eventually a power test up to clipping. 40 years after starting to build amps I am at last learning something! ��
awkwardbydesign,
Good going!
After building vacuum tube receivers and amplifiers since 1958, I am still learning too.
During part of my carrier, I had access to a $50,000 Vector Network Analyzer that could test from 10Hz to 4GHz.
I tested audio transformers, complete triode non-fedback amplifiers, loudspeakers, and speaker cables.
I tested damping factor versus frequency, frequency response, phase versus frequency, and gain of amplifiers;
loudspeaker impedance and phase versus frequency;
speaker cable insertion loss, reactance versus frequency, and frequency response versus drive and loading resistance;
And tested the combined electrical frequency response and phase of the amplifier plus loudspeaker (not the acoustic measurements).
I also tested interstage and output transformers for frequency response, leakage reactance, capacitance, phase versus frequency, insertion loss versus frequency, and impedance versus frequency.
It was nice to set up a test with the Vector Network Analyzer.
Now I do those tests manually, with my own test equipment, far less expensive, just more work.
Good going!
After building vacuum tube receivers and amplifiers since 1958, I am still learning too.
During part of my carrier, I had access to a $50,000 Vector Network Analyzer that could test from 10Hz to 4GHz.
I tested audio transformers, complete triode non-fedback amplifiers, loudspeakers, and speaker cables.
I tested damping factor versus frequency, frequency response, phase versus frequency, and gain of amplifiers;
loudspeaker impedance and phase versus frequency;
speaker cable insertion loss, reactance versus frequency, and frequency response versus drive and loading resistance;
And tested the combined electrical frequency response and phase of the amplifier plus loudspeaker (not the acoustic measurements).
I also tested interstage and output transformers for frequency response, leakage reactance, capacitance, phase versus frequency, insertion loss versus frequency, and impedance versus frequency.
It was nice to set up a test with the Vector Network Analyzer.
Now I do those tests manually, with my own test equipment, far less expensive, just more work.
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