Thread: Thandar TG2001
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Old 11th May 2021, 2:43 pm   #5
Marconi_MPT4
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Join Date: Mar 2011
Location: Dorset, UK.
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Default Re: Thandar TG2001

Although configured for 240V, looking at the secondary voltages on plug PJ5 I have the following measurements relative to T3 (black wire):
T1 Yellow 23.7V
T2 Orange 19.9V
T3 Black (reference 0V)
T4 Orange 19.8V
T5 Yellow 23.5V

Overall secondary voltage is approximately 47.2V AC between T1 and T5 (yellow wires) and is within ballpark of 50V measured. On that basis the transformer primary configuration appears to be correct.

Fuse rating would have to be increased for 120V operation. According to details printed on the back panel you should use a 500mA(T) 250V HRC 5x20mm. Surprising to see that power consumption is 50W (!)

Which pair of regulators are overheating as this may help diagnose which part of the circuit is at fault? There are at least eight but If IC29 and IC30 are cooking then it clearly points to excessive current being drawn by the output amp or something associated with it.

Rich
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