Oh no...speedball not working. [solved]

[Maynard]

Hey all, last night I finished the speedball upgrade after a few weeks with the stock crack working flawlessly. I have triple checked that all the connections are in the right places, however when I turned it on all of the leds lit up dimly, EXCEPT THE D2 ON BOARD B AND THE INNER LED ON THE HEATSINK BOARD NEAREST THE POWER SUPPLY.

The capacitor, (or something under it) in terminals 14 and 15 got very hot and let out a wisp on smoke. I quickly turned it off. So tonight I turned it on again and the same one or two leds turned on, (both tubes glowed fine), so I left it on for about 3-4 minutes, and watched the area of the capacitor. It started to smoke again so I switched off. It was hot again I could feel it with my hand hovering over it.
At one point before I had installed any of the speedball, I dropped the crack on the workbench, only from about 3 inches but maybe the bump against the table top may have damaged something.
Also there wasnt much slack on the leads of the two capacitors that needed to be bent down to allow the pcb board to sit properly, so when I bent them down, the posts they were connected to also bent quite a bit. Hopefully the photo illustrates this ok. Thanks, please have a loot at the photos.

[Maynard]

Just thought i'd add that in the photos it doesn't look like any of the leds except one light up but i turned the lights off and all were glowing except two that I mentioned in the previous post.

[Paul Birkeland]

This kind of issue is almost always an issue with installation of the insulators on the TIP-50 transistors.

You can confirm this by running the Crack without the 6080 installed, then measure the voltages on terminals 1, 2, 4, and 5.

If terminals 2 and 4 measure above 150V DC, you won't be smoking the power supply.

If you pull the 6080 and there's still an overheating issue in the power supply, let us know.

I can't quite tell in your photos, but it looks like one of the shoulder washers on one of the TIP50 mounting kits may be in backwards.  They are intended to keep the body of the screw from touching the heatsink.

-PB

[Maynard]

Great thanks Paul, will have a look!

[Maynard]

just checking the heatsinks and the way I installed them is the way that is stated in the manual. The shoulder washer is the one with little protruding lip on one side of the washer right? And the lock washer is the one with cut in one place?

[Maynard]

yep definitely installed correctly, now I'l try pulling the 6080 etc...

[Maynard]

Ok, tested the voltages
T1 88v
T2 213v
T4 213v
T5 210v
There is no smoke coming from the cap area now. cool as a cucumber! What a relief.
Thanks Paul, now what?!

[Paul Birkeland]

Remove the 2N2222 from the side giving you 210V on T5 and swap it for the 2N2907 that must mistakenly be installed on the big PC board.  (didn't notice this until now)

Test again first with just the 12AU7, then test with the 6080.  It is possible that you will need to replace some transistors if the voltages don't come out properly.

-PB

[Maynard]

Okay so those two components look the same? Both little silver capped three pronged things? Away from the build right now

[Paul Birkeland]

Yes, except for the writing.  2N2907's go on the little boards, 2N2222's go on the big boards.

[Maynard]

Damn and double damn. Oh well you live and learn.

[Maynard]

What and where are the most likely things that would have to be replaced as a result of this mistake? Thanks!

[Paul Birkeland]

It'll be much easier to tell once you retest your voltages.

The likely items are the 2N2907, 2N2222, MJE-350, and TIP50 in the areas where you will be swapping transistors. The other sides that were outfitted correctly can be left alone.

-PB

[Maynard]

Ok here's with no 6080
No 6080
T1 94.5
T2 222.6
T3 0
T4 220
T5 86
T6
T7 1.543
T8 0
T9 1.531
T10 0
T11 0
T12 0
T13 219
T14 0
T15 226
T20 0
T21 231.9

[Maynard]

And with 6080
With 6080
T1 97.7
T2 182.6
T3 0.7
T4 182.5
T5 88.3
T6 fluctuations mv
T7 122.6
T8 0
T9 115.2
T10 fluctuations mv
T11 0.7 mv
T12 0
T13 176.5
T14 0
T15 197.3
T20 0
T21 216.7