27-01-2017, 02:05 AM
" learn about voltage and current behavior with resistance, reactance and impedance, ohms law formula is your friend here as it can be applied to all those three, just change the term,...."
I think you indicate the voltages in transformers are always induced by the change in field. Therefore not DC. In the case of the output transformer, the primary of course is used as the optimum load of the output valve. The secondary will have a turns ratio matched to the speaker.
I seem to vaguely recall Chas Miller commenting on this in his book but I no longer have the copy.
However, yes, I am familiar with capaciive reactance and inductive reactance formulae, phase, voltamps and power factors. I do marine electrics as well so some of it I learned in that area.
One interesting sum I use for transformers is my so-called "magic number sum".
If primary has 400 turns but current unknown
Secondary has 2800 turns and a known current of 0.2 amp
Multiply 2800 by 0.2 equals 560
The number 560 applied to the turns ratio of the primary must indicate the primary current. So dividing 400 into 560 gives 1.4
The kicker is the stepped down winding with the lower voltage will have the higher current and all induced voltages will oppose each other.
Not that it's not common knowledge but I like to experiment with the theoretical stuff.
I think you indicate the voltages in transformers are always induced by the change in field. Therefore not DC. In the case of the output transformer, the primary of course is used as the optimum load of the output valve. The secondary will have a turns ratio matched to the speaker.
I seem to vaguely recall Chas Miller commenting on this in his book but I no longer have the copy.
However, yes, I am familiar with capaciive reactance and inductive reactance formulae, phase, voltamps and power factors. I do marine electrics as well so some of it I learned in that area.
One interesting sum I use for transformers is my so-called "magic number sum".
If primary has 400 turns but current unknown
Secondary has 2800 turns and a known current of 0.2 amp
Multiply 2800 by 0.2 equals 560
The number 560 applied to the turns ratio of the primary must indicate the primary current. So dividing 400 into 560 gives 1.4
The kicker is the stepped down winding with the lower voltage will have the higher current and all induced voltages will oppose each other.
Not that it's not common knowledge but I like to experiment with the theoretical stuff.
