Fresh Elekit TU-8500 Build with NO output?

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Hello, I just finished the build and am getting no output and don't know why or what else to check to isolate the problem.

I have checked voltages at all 3 test points. I got 136.2V at the 140V test point and 12V/12.12V at the two 12V test point(s) and also 12.2V at the single 12V test point. Tubes light up. LED stays off when turned on unless I push down hard on either the CN1 or CN7 connector, or D1, D2, D3 (3 lower diodes). Although both connectors are snapped perfectly in place and solder joints all look good underneath. Even when I get the LED to temporarily light up, there is still no sound output.

Pictured are ShuGuang Sounds of Nature 12AT7's. I also tried the Chinese 12AU7's to rule out the tubes- there is no sound output with either set of tubes. Does anything look out of place or does anyone have any idea what may be wrong? Thank you.
 

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I've never tested tubes before, but here are the results for one using this pic as a guide. I measured voltage across the pins of these corresponding pairs.

Pins
2-7 Grid Triode 53.1 VDC
1-6 Anode Triode 75.6 VDC
3-8 Cathode Triode 57.3 VDC
4-5 Heater Triode 12.04 VDC
9-Ground Heater Center Tap 6.04 VDC

Results for V2
2-7 Grid Triode 44.5 VDC
1-6 Anode Triode 70.7 VDC
3-8 Cathode Triode 61.7 VDC
4-5 Heater Triode 12.02 VDC
9-Ground Heater Center Tap 5.92 VDC
 

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Good question. When I push on CN1 or CN7 or D1-D3, sometimes it blinks intermittently on and off, other times it just stays solid until I let go. IC's? Maybe some internal processing error? Otherwise, all components look visibly good. I tried reading some kind of error message through the blinks, but they were just steady on and off.
 
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Thank you. I figured out what was wrong and I kind of doubt it would ever happen to anyone else but one of my board binding posts was not quite tight enough. It also happens to be labeled "SG" (shared ground) and was responsible for the LED turning on and blinking intermittently when I pushed down on a few of the components in the nearby vicinity.



As to the other issue of no sound output, the furthest pair of legs on the relay were in fact not soldered as vkung suggested. It is now sounding great. Thanks everyone.
 
Launch! So natural and clear, upper frequency extends really high without hurting my ears. Vibrant and dynamic lower end frequency {bass response} and texture. Signal remains clean and pure even at higher amplification levels. Smooth, natural, and extremely detailed- it's definitely a keeper and hopefully just my first build from Elekit.
 

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