Where are we up to 
Morning Sakis... today... it will work
Easy one first. LTSpiceIV from here, Winodws or MAC as appropriate. Links at right of page.
Linear Technology - Design Simulation and Device Models
Methinks your speaker switch is OK. With the speaker switch set to A the speaker terminals should read short to chassis from the negative speaker terminals and each of the positive terminals should read "short" to the output of each amplifier as appropriate.
So where are we at ?
Morning Sakis... today... it will work Easy one first. LTSpiceIV from here, Winodws or MAC as appropriate. Links at right of page.
Linear Technology - Design Simulation and Device Models
Methinks your speaker switch is OK. With the speaker switch set to A the speaker terminals should read short to chassis from the negative speaker terminals and each of the positive terminals should read "short" to the output of each amplifier as appropriate.
So where are we at ?
sakis! good morning sir. yes, that makes sense, and i see in the schematic that there are a couple of 40K resistors there that engage when that set of speakers are not in use. very good, thanks.
please ignore the readings for speaker terminals above. seems i did not remove the darn-nab speakers before i took the readings. like i said, "duhh".
now, does this seem right for the terminals?
speakers-
switch position "OFF"
speakers A
L+ = open
L- = 11 K
R+ = open
R- = 11 K
speakers B
L+ = open
L- = 11 K
R+ = open
R- = 11 K
switch position "SpeakersA"
speakers A
L+ = 200 K
L- = 0 (short)
R+ = 200K
R- = 0 (short)
speakers B
L+ = open
L- = 0 (short)
R+ = open
R- = 0 (short)
Switch position "SpeakersB"
speakers A
L+ = open
L- = 0 (short)
R+ = open
R- = 0 (short)
speakers B
L+ = 200 K
L- = 0 (short)
R+ = 200 K
R- = 0 (short)
Speaker position "A + B"
speakers A
L+ = 200 K
L- = 11 K
R+ = 200 K
R- = 11 K
speakers B
L+ = 11 K
L- = 0 (short)
R+ = 11 K
R- = 0 (short)
so, can i deduce from this that yes, indeed, when A + B is selected, the speakers are put in series, thus me not hearing anything from speakers A when in A+B position? and, can i deduce that the switch is fine?
aidan
please ignore the readings for speaker terminals above. seems i did not remove the darn-nab speakers before i took the readings. like i said, "duhh".
now, does this seem right for the terminals?
speakers-
switch position "OFF"
speakers A
L+ = open
L- = 11 K
R+ = open
R- = 11 K
speakers B
L+ = open
L- = 11 K
R+ = open
R- = 11 K
switch position "SpeakersA"
speakers A
L+ = 200 K
L- = 0 (short)
R+ = 200K
R- = 0 (short)
speakers B
L+ = open
L- = 0 (short)
R+ = open
R- = 0 (short)
Switch position "SpeakersB"
speakers A
L+ = open
L- = 0 (short)
R+ = open
R- = 0 (short)
speakers B
L+ = 200 K
L- = 0 (short)
R+ = 200 K
R- = 0 (short)
Speaker position "A + B"
speakers A
L+ = 200 K
L- = 11 K
R+ = 200 K
R- = 11 K
speakers B
L+ = 11 K
L- = 0 (short)
R+ = 11 K
R- = 0 (short)
so, can i deduce from this that yes, indeed, when A + B is selected, the speakers are put in series, thus me not hearing anything from speakers A when in A+B position? and, can i deduce that the switch is fine?
aidan
ahh, okay, thank you.beats watching a meter or scope when doing adjustments. you'd need a third eye LOL
Hold it there... that is measured from chassis to Re19, yes.
What is the voltage on the Qe7 end of Re19
1.2 volt sounds OK.
Big question... does the voltage across Qe7 vary with the pot. Reading to those points from chassis wont work because both points could be moving up and down together. Its got to be across Qe7.
What you got, maximum and minimum readings.
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