F6 Amplifier

lf the windings on the secondaries are assymetrical that is to get equal summing of gain at the output. Then you have true symmetry
That is if the voltage gain of the secondary going to the source follower (common drain) is equal to tne voltage gain of the common source device then you have symmetry. So one secondary has voltage gain but the other does not have voltage gain
 
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In the J/PLH, the phase spliter (driver) signal presented to the comon source output transistor is the same polarity and level as presented to the driver itself. However, the signal from the Drain of the driver transistor to the Source Follower output transistor is opposite phase.
In the F6 scheme, the signal present to the transformer (driver) is passed through the transformer with some turns ratio (gain) ??? And, the polarity of the signal presented to both output transistors is the same.
 
The feed back is suming some portion of the output voltage with an opposing input voltage(oh boy, here we go?). For instance, if you only had a gnd on the input primary, instead of those resistors, it would see the full input signal. If the feedback resisters xfrm'r etc. caused that node to have 1/2 the signal level of the input voltage, the primary would only effectively have 1/2 the voltage :D
 
Official Court Jester
Joined 2003
Paid Member
...... ZEN MOD you began analyzing its operation [bolded],and may need to continue to explain it further for our benefit.

no need for that , I already made enough a fool of my self in this thread :clown:

there are just two possible paths - either modulating gates in antiphase (so result is push pull or sort of ) ....... or in phase , but with upper modulation smaller than lower one .
that way effects can be interesting - varying difference in modulation will vary your amount of Zen :rofl:

call it xformerised thingie fooling around , same as Mu , following some other paths

don't be surprised if full schm reveal some other wakoo ways of Zen practice ;

Papa is often having redish eyes ........

:devilr:
 
Official Court Jester
Joined 2003
Paid Member
lf the windings on the secondaries are assymetrical that is to get equal summing of gain at the output. Then you have true symmetry
That is if the voltage gain of the secondary going to the source follower (common drain) is equal to tne voltage gain of the common source device then you have symmetry. So one secondary has voltage gain but the other does not have voltage gain

yadayada

(imagine picture of Manuel "Que?" here ............ )

The surprise is the bloody feedback loop

hardly , if you ever burned anything yours on hot tube ; but (as usually) hat off to Pa , for taking old tricks from hat

real surprise is twisting da twist - using xformer instead of current mirrors

again .......... out of box ; lateral thinkin'
 
I thought that was every time.
Not so fast buzzforb; there is another way to cheer Mr. Pass. He may chose to smile instead knowing the onus is on us DIYers to understand the F6 circuit. Let us remember that our motto is DIY: Do It [the experiments] Yourself. The attached pdf [OTLAmp2] shows a safe and practical schematic to understand the F6 circuit. Use a low +/- Vc and high values for R to safeguard the bjts or others. The phase of the secondaries of the interstage transformer [toroid or iron core] can be connected [at will] one of two ways: In or Out of phase. Compare the attendant useful output power in a non inductive 8 Ohm load. The bottom right corner of the pdf shows a possible way to understand the F6 circuit by SIMULTATION [lucky you DIYers who have this capability]. Again the signal sources can be In or Out of phase.
 

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If we seperate the two output halves... The top follower would present a signal at the output that would be in phase with the input, but, the feedback is fed to the - side of the primary allowing for - feedback.
The bottom transistor feeds the output node out of phase. If this signal were the majority of the feedback signal it would be positive feedback. Oscilators are designed with positive F.B. :eek:
I don't know it all either??? If the output haves were effectively outputing the same signal, there would be no F.B. If one is distorted and the other not, there would be F.B. correcting the distortion
 
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If we seperate the two output halves... The top follower would present a signal at the output that would be in phase with the input, but, the feedback is fed to the - side of the primary allowing for - feedback.
The bottom transistor feeds the output node out of phase. If this signal were the majority of the feedback signal it would be positive feedback. Oscilators are designed with positive F.B. :eek:
I don't know it all either??? If the output haves were effectively outputing the same signal, there would be no F.B. If one is distorted and the other not, there would be F.B. correcting the distortion

Your continued analysis of the F6 circuit is beneficial and worthwhile. best regards.