The calibration is a gimmick. Yes, it only needs some sine voltage to be fed to the input tx secondaries center tap to check for matching of the ef83s. This way one calibrates for maximum cancelation. One could also calibrate for maximum voltage before the first gain stage. I put A LOT of test points all over the board. No need to worry too much about the 12V for calibration.
Rohde und Schwarz Begrenzungsverstärker ABR / U23
- Thread starter Falk
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Ich found this one:
https://www.don-audio.com/Audio-Toroidal-Transformer-Pri-2x115v-Sec-240V-50V-2-x-12V
This should work.
https://www.don-audio.com/Audio-Toroidal-Transformer-Pri-2x115v-Sec-240V-50V-2-x-12V
This should work.
Hey Folks,
is anyone here quick and good in designing frontpanels?
Maybe someone could design a panel for this particular built we all can use.
Maybe even a group buy of panels is possible.
Me personally I'd like a design which is reminiscent of the Vacouvox design or Thermionic Culture Phoenix and the likes.
is anyone here quick and good in designing frontpanels?
Maybe someone could design a panel for this particular built we all can use.
Maybe even a group buy of panels is possible.
Me personally I'd like a design which is reminiscent of the Vacouvox design or Thermionic Culture Phoenix and the likes.
Would you or somebody else be so kind to explain how to propperly simulate a compressor in Spice?
I've simulated a few vari mu circuits and frequency response, gain and voltages seem to be good but when trying to somehow plot the compression I get weird results. I tried it with stiff supplies e.g. batterie supplies but also with "normal" power supplies. What puzzles me is that the controlls somehow work but the gain is always way to high at the output... So when feeding something like 1Vpeak I get the amplification of the whole amp at the output and the waveform is severely distorted.
What exactly are you plotting? I would assume the transient response, right?
Edit: just found this interesting thread and will try to grasp it all: https://gearspace.com/board/geekzone/1184274-gyraf-ssl-ltspice-simulation.html
I've simulated a few vari mu circuits and frequency response, gain and voltages seem to be good but when trying to somehow plot the compression I get weird results. I tried it with stiff supplies e.g. batterie supplies but also with "normal" power supplies. What puzzles me is that the controlls somehow work but the gain is always way to high at the output... So when feeding something like 1Vpeak I get the amplification of the whole amp at the output and the waveform is severely distorted.
What exactly are you plotting? I would assume the transient response, right?
Edit: just found this interesting thread and will try to grasp it all: https://gearspace.com/board/geekzone/1184274-gyraf-ssl-ltspice-simulation.html
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I don’t know if I missed it in this thread but can somebody please explain what’s exactly going on with the screen grids and cathodes of the varimu tubes? Is that some kind of feedback?
When simulating and comparing to other more "simple" circuits it seems as if the plate and screen voltage pretty much stay constant while in the other circuits they vary quite much with gain reduction.
I just realized that the RCA BA-6A has a quite similar arrangement.
When simulating and comparing to other more "simple" circuits it seems as if the plate and screen voltage pretty much stay constant while in the other circuits they vary quite much with gain reduction.
I just realized that the RCA BA-6A has a quite similar arrangement.
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