Gyraf G9 help

[Orphin]

Hi guys!

Just finished building the Gyraf G9 and I have three problems. I'm just throwing a bone to see if any of the following problems are anything you've heard about before:

1, A wierd problem. It seems to run fine for a couple of minutes, but then shuts down. Seems like it has to cool down before it can restart again.
(I use heatsinks for all the transistors except TIP121)

2, The output volume differs a lot between the two channels. Assuming the the tubes are OK, what else could it be?

Thanks in advance

 

[gemini86]

1) what shuts down? Hv? Heaters? Mains power?
2) check all resistors for correctness.
3) this should be in the official help thread.

 

[Orphin]

1, The mains
2, I guess I could go through them all, although I've been very thorough when building it.
3, Didn't know that an official help thread existed. The text under "The Lab" said: "Building & Troubleshooting" to I figured this was the correct place to post.

 

[gemini86]

To be clear, I meant mains as in wall power.

Here's the help thread. http://www.groupdiy.com/index.php?topic=17980.0

This project has been around so long there are bound to be answers for you there.

 

[Orphin]

To be clear, I meant mains as in wall power.

Yes, me too.

 

[gemini86]

So your house wiring shuts off for a few minutes, then comes back on?  Is your circuit breaker tripping? Are you using the back to back transformer arrangement and if so, what va rating are they?

 

[gyraf]

Please use the designated G9 help thread - http://www.groupdiy.com/index.php?topic=17980.0

Jakob E.

 

[Orphin]

So your house wiring shuts off for a few minutes, then comes back on?  Is your circuit breaker tripping? Are you using the back to back transformer arrangement and if so, what va rating are they?

No, not the entire house. Only the apparatus mains.
I'm using two torroid transformers rated at 30VA in the back to back arrangement.

 

[gemini86]

Hop on over to the official thread please. Post your original problem with exactly where you loose power, pictures also help.

 

[Orphin]

Hop on over to the official thread please. Post your original problem with exactly where you loose power, pictures also help.

No need. I figured out the problem.
It's the 12V regulator that gets too hot. I fitted larger heatsink but it only prolonged the time before it shuts down. I figure I just have to get a ridiculously large heatsink and fit it directly on the backpanel and run wires to the PCB instead.

Thanks anyway! Cheers.

 

[gemini86]

Then that's not your mains shutting down, is it?

 

[Orphin]

Then that's not your mains shutting down, is it?

No, I got fooled because the power lamp is on the 12V line.  :-[