First kit ......smoke signals!

[mstenkilde]

Hello Everyone,

Well - I got the Reduction phono pre-amp a long time ago - and finally got around to assemble it - unless it has a built in smoke signal error signal mechanism ..i messed up bad.

I think I got ahead of myself and assembled a little too quickly (especially considering I am new to everything..soldering, electronics etc) and I made 2 (at least) fatal errors

1) I did NOT conduct the resistance check prior to powering on (I did not have a meter and was too impatient to get one ....)
2) I did NOT put the tubes in before powering up.

Please note that I am not proud of this - but I am including the information in case it can help trouble shooting.

Upon power-up - a thin pillar of smoke appeared and I immediately pulled the power cable.

I am hoping someone on these forums can help me with tips on further trouble shooting and help me find out which parts I need to replace (I assume smoke means something is toast)

I did the resistance check now - and most of the values are where they need to be, here are a few notable exceptions:

11 (should be 0) - 1.2
33 (should be close to 0) - 3
38 (should be close to 0) - 3
42 (*) - 2.7
50 (*) - O.L
51 (*) - O.L
56 (*) - O.L
57 (*) - O.L
60 (*) - O.L

Where do I go from here? What are good next steps to isolate/fix the problem?

Thank you VERY much for any help you can provide

Martin

[Rocketman248]

First thing to do would be to go back through the manual step by step, and verify everything was installed properly.  Take your time on this.  I know all too well of the temptation to rush through steps because you're excited to use it. Take your time, and double check everything.

I would especially focus on the orientation of the capacitors and diodes in the power supply.  Mixing one of those up could have some nasty outcomes.

If you're still stuck, post some pictures of your build.  Someone may be able to spot something.

[frank bare]

I know this has been spelled out many times before. What works for me,

Slow down.
Get a magnifier and review each step, before going on to the next.
The best solder joint will fool you...it did me. Recheck the connection before going on to next step.
Take a breather, go for a walk around the block.

I would not have the patience of having a BH kit and not building it. It's easy to get caught up in the excitment and end result.

I too want to build a Reduction...my next project for sure.

Don't get frustrated. You will resolve this. And have a double sense of accomplishment. Give it time.
Bare

[mstenkilde]

Hi!

Thank you both for your solid advice - go through everything again, take my time

I did - and in doing so I found where the smoke came from ( see attached pics)

I found nothing else - but here is a question. I think that 1N5818 was part of the heating circuit ...since I can find nothing else wrong - would be a feasible explanation that powering up WITHOUT the tubes in would overheat this component?

I have ordered new ones online - I plan to replace it and try again ... I will let you know what happens

Thanks,
Martin

[Paul Birkeland]

If you power up your Reduction without any tubes installed, almost all of your voltages will be wrong.