You are correct, around 2 watts in triode mode give-or-take. The "RH" mode is pentode with plate-to-plate feedback. (Or Schade feedback after O. H. Schade, or more correctly Plate-to-Grid feedback. AFAIK.) It should yield around 4-5 watts. Note the distortion level for 5.7 watts on the datasheet.
This style of feedback is a very short loop that does not include the output transformer. It serves to drastically lower the plate resistance of the output tube so as to better utilize the inductance of the output transformer and improve frequency response and damping factor as compared to pentode mode with no feedback.
This style of feedback is a very short loop that does not include the output transformer. It serves to drastically lower the plate resistance of the output tube so as to better utilize the inductance of the output transformer and improve frequency response and damping factor as compared to pentode mode with no feedback.
Is that chassis 5G29? Schematic is online: http://techpreservation.dyndns.org/schematics/62/62_Zenith_5G29_157.djvu (you'll need the DjVu plug-in to view or print it).
Hey Guys,
I don't think mine is a 5G29 but it is really close. Mine has four pots instead of three and all the transformers are at right angles. What I need the schematic for is the power transformer. I haven't been able to figure out which is the mains winding. I have two green with a green/white centertap. Two white/red with a white center tap. Two yellow and two kinda dingy white maybe brown? The yellow leads are slightly heavier gauge.
I tried downloading djvu something started a scan? Virus? I was rushing because you're all online. Four watts is much better. I'll try to find a better source for the software and download the schematic.
I don't think mine is a 5G29 but it is really close. Mine has four pots instead of three and all the transformers are at right angles. What I need the schematic for is the power transformer. I haven't been able to figure out which is the mains winding. I have two green with a green/white centertap. Two white/red with a white center tap. Two yellow and two kinda dingy white maybe brown? The yellow leads are slightly heavier gauge.
I tried downloading djvu something started a scan? Virus? I was rushing because you're all online. Four watts is much better. I'll try to find a better source for the software and download the schematic.
Hey Guys,
I've finished the RH84. My power transformer put out 740 volts so my B+ is higher than spec. So I bought EL84M's. I'm noticing a bit of distortion in the lower frequencies. Is it a safe assumption that since the amp originally ran 375 volts of B+ that the output transformers are capable of dealing with it? I measure 288 volts across the tube and they are drawing 37ma. Am I exceeding the capability of the OPT? Or is the distortion coming from somewhere else?
I've finished the RH84. My power transformer put out 740 volts so my B+ is higher than spec. So I bought EL84M's. I'm noticing a bit of distortion in the lower frequencies. Is it a safe assumption that since the amp originally ran 375 volts of B+ that the output transformers are capable of dealing with it? I measure 288 volts across the tube and they are drawing 37ma. Am I exceeding the capability of the OPT? Or is the distortion coming from somewhere else?
Thanks everyone! The amp is finished. The distortion was because my audio research was over driving the amp. I plugged my planet directly into it and it sounds wonderful. Its not a powerhouse but the tone is near perfect. Well, its better than my tired old ears can hear that's for sure.
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