I will analyze the possibility of increasing the output power of the amplifier on the 6F4P radio tube. The audio output transformer for this amplifier will be designed with screen and cathode windings, allowing you to test the final stage of the amplifier with different pentode connection schemes. The resulting oscillograms will clearly show the effect of the cathode winding of the audio output transformer on the amount of harmonic distortion, on the output power of the amplifier and on its amplitude-frequency characteristic. I hope this video will be interesting not only for novice radio amateurs. Whenever possible, text materials describing the circuits and calculating the cascades are also attached. For those who want to translate the text of the video into other languages, a file with the full text of the video is attached - for substitution in an electronic translator. *** You can help develop the Channel: Yandex Money: https://yoomoney.ru/to/410013004521132 VISA (Russia) 4048-0250-0094-9167 This makes it possible to purchase the necessary electronic components for shooting videos according to your requests. Thank you for your help, friends! *** Link to video materials: https://drive.google.com/drive/folder... Playlists: "Sound Amplifiers" • SRPP Results of tuning and tests "Radio tubes I-V characteristic THD IMD frequency response" • Radio tubes I-V characteristic THD IMD frequency response "Output transformer for tube amplifier" • Output transformer for tube ... "Tube SE amplifier. Test drive of pentode switching modes" • Tube SE amplifier. Test drive m... "Tube SE amplifier. Comparison of pentode switching circuits" • Tube SE amplifier. Comparison of circuit diagrams... "6F4P Two-stage amplifier" • 6F4P Two-stage amplifier "Calculation of a two-stage amplifier on a 6F4P radio tube" • Calculation of a two-stage amplifier on a ra... "Tests of audio output transformers." ( • Tests of audio output transformers. ) "Electronic choke of anode power supply" • Electronic choke of anode power supply. "6F4P I-V characteristic THD IMD frequency response" • 6F4P I-V characteristic THD IMD frequency response "Passive tone controls. Psychoacoustics" • Passive tone controls. Psychoacoustics... "Tone control. Equalizer. Equalization" • Tone control. Equalizer. Equalization... 00:00 Welcome to the "Unknown Physics" channel! 00:15 A question about increasing the power of the amplifier. 00:30 Passport of the 6F4P radio tube. 01:00 Extended I-V characteristic of the pentode section in the triode connection of the 6F4P radio tube. 01:13 Results from moving the operating point over the allowed region. 05:40 Calculation of the audio output transformer. 06:21 Formulas for an ideal transformer. 07:15 Influence of hysteresis. 08:24 Practical calculation of the audio output transformer. 09:48 Nomograms of the overall power of the transformer. 10:06 Data from low-power TVZ. 10:31 Formulas for calculating TVZ. 11:35 Winding wire. 11:54 Calculation of a transformer with grid and cathode windings. 12:14 Calculation of the non-magnetic gap of TVZ SE. 13:00 Data from the TV-2A audio output transformer. 13:36 The audio transformer used in the test. 14:15 First test of the calculated operating point of the final stage with a test TVZ. 17:11 Slides showing the appearance of signal harmonics. 17:33 Expected output power. 18:02 Actual output power. 18:41 Frequency response of the final stage with a test TVZ. 19:32 Triode connection of the pentode with a cathode winding. 20:18 THD of the stage with triode connection of the pentode with the cathode winding. 21:52 Comparison of THD of triode connection of the pentode with the cathode winding. 22:08 Reverse phasing of the cathode winding. 22:27 Frequency response of the final stage with the cathode winding of the test TVZ. 23:29 Measuring intermodulation distortion of the final stage with the cathode winding of the test TVZ. 25:11 Why was this particular circuit and this transformer taken for the test? 25:47 Comparison of THD in the circuit with and without the cathode winding. 26:21 Comparison of the frequency response in the circuit with and without the cathode winding. 26:47 Pentode connection circuits for the next video. #6Ф4П #Amplifier_Calculation #TVZ_SE_Calculation #Sound_Amplifier #Two-Stage_Amplifier QUESTIONS can be asked in the comments to any video, on social networks and by e-mail to the channel: [email protected] I answer all SPECIFIC questions. I hope that your questions and joint answers will help make the channel "Unknown Physics" more interesting! **************************************************************** LINKS to the channel's videos are posted on personal pages in social networks and in groups: Add me as a FRIEND! (When adding, PLEASE write - where are you from and on what issue) e-mail: [email protected] VKontakte: htt