[hasanova]

Hi,

I've built two TS500's. One is working with correct output voltages. The other has no output.
- Correct power voltages (+16/-16 VDC).
- Peak-meter is working and I can set it correctly.
- I've swapped all IC's, on both units, but still no output.
- I've Re-touched solder joints, still no output.
- I've compared continuity on the transformers of both units, but both were still in circuit.

Where should I look?

[JPK]

Check there is no DC voltage on TP7.
Check if you can follow the signal with your AC voltmeter on TP3, TP4, TP5, TP6 and TP7.

[hasanova]

Conditions	OUTPUT = 26.6 mVAC	TP7 = 0.376 VDC
input signal = sine 1kHz 0.4 VAC	OUTPUT = 0.00 VDC	TP3 = 2.439 VAC
(on input XLR between pins 2&3)		TP4 = 2.439 VAC
30” dpi		TP5 = 2.433 VAC
TAPE SAT on left (min)		TP6 = 2.231 VAC
BIAS/EQ on right (flat)		TP7 = 4.178 VAC
Both pots on 10
TS500 ON

[JPK]

Check the output transformer coils resistors:
- between TP7 and 0V : 5.2 ohms
- between output hot and cold : 23 ohms

[hasanova]

I had trouble logging in on the forum for a while, but in the end we sorted it out: it was a defect in the output transformer.
I already swapped it for a new one, all is well in Audio-Land

Thank you JPK!