Quote:
200Ohm range:
R26 & R27 - where;
TR6 base was connected = 34.5
TR7 base was connected = 37.5
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That's OK. Approximately 35 ohms in each half of the winding.
Quote:
2000mV;
TR6 base was connected =194
TR7 base was connetced =195
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That's OK too. Approcimately 200mV or 0.2V on each point. If there were a short circuit between primary and secondary (ie a fault condition) There would have been a higher reading.
I am at a loss to explain why you saw first 0V and later 4.6V on TR6 base. Visually check for breaks in the track going to TR6 base and contacts with other tracks.
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While the output transistors are out check the windings on T2:-
Resistance readings are always measured with the set turned off.
T2 primary. Measure resistance between chassis and the points where TR6 and TR7 emitters were connected.
T2 upper secondary. Battery removed. Measure resistance between the negative battery lead going into the set and the points where TR6 and TR7 collectors were connected.
Measure the resistance of R30 and tell us what its colour code is.
T2 lower secondary. Disconnect one lead of the speaker. Disconnect one end of R28. Measure the resistance between the speaker wires going into the set. While R28 is disconnected you might as well check its value. Reconnect speaker and R28.
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Now for some voltage readings. Voltage readings are always taken with the set turned on.
T2 primary. Measure the voltage between chassis and the point where the TR6/7 emitters were connected. Expect a low or zero reading.
T2 upper secondary. Measure the voltage between chassis and the point where the TR6/7 collectors were connected. Expect to see the full battery voltage.
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It would be a good idea to check the operation of your meter's 20mA range.
Battery out of set. 2.2K resistor (a spare one, not the one in the set) to positive of battery. Positive lead of meter to other end of resistor. Negative lead of meter to negative side of battery. Expect a reading of about 4 to 5mA.