Author Topic: No Output - solved!

December 08, 2022, 08:25:11 PM
Read 671 times

hasanova

  • Newbie
  • *
  • Posts: 11
  • Karma: +0/-0
    • View Profile
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?
« Last Edit: December 22, 2022, 07:17:58 PM by hasanova »

December 10, 2022, 11:31:55 AM
Reply #1

JPK

  • Administrator
  • Hero Member
  • *****
  • Posts: 1015
  • Karma: +30/-0
    • View Profile
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.
JPK

December 10, 2022, 08:54:49 PM
Reply #2

hasanova

  • Newbie
  • *
  • Posts: 11
  • Karma: +0/-0
    • View Profile


ConditionsOUTPUT = 26.6 mVACTP7 = 0.376 VDC
input signal = sine 1kHz 0.4 VACOUTPUT = 0.00 VDCTP3 = 2.439 VAC
(on input XLR between pins 2&3)TP4 = 2.439 VAC
30” dpiTP5 = 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

December 11, 2022, 11:05:51 AM
Reply #3

JPK

  • Administrator
  • Hero Member
  • *****
  • Posts: 1015
  • Karma: +30/-0
    • View Profile
Check the output transformer coils resistors:
- between TP7 and 0V : 5.2 ohms
- between output hot and cold : 23 ohms
JPK

December 22, 2022, 07:17:25 PM
Reply #4

hasanova

  • Newbie
  • *
  • Posts: 11
  • Karma: +0/-0
    • View Profile
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!