Crate FXT30

[JoeM]

Anyone with a schematic for a Crate FXT30 amplifier?

Thanks!

[JoeM]

I contacted Loud and am waiting for reply. In the mean time if anyone has the schematic, I need the value of R63, located on the Power amp board. (Burnt -can't read the value)

[edit]

Got it!

[Jazz P Bass]

All that I have is the FXT65.
Maybe something will be close enough to give you a clue.

[JoeM]

Thanks Jazz. I e-mailed Loud and after they sent an agreement back that I couldn't disclose the schematic, they sent just what I needed.

[Jazz P Bass]

For grins & giggles, what is even close?

[JoeM]

Not sure. The FXT30 uses a TDA2050 for the output rather than discrete transistors. The TDA2050 is completely fried in the amp along with R63, (1ohm - burnt to where I couldn't read the color codes)

[Jazz P Bass]

1 ohm?
Is that part of the zobel network? (a resistor & a capacitor off of the output, to ground)

[JoeM]

Yes. The 1 ohm is in series with a .22 cap to ground. Any ideas why this would fry?

[Jazz P Bass]

Cannot say when but at some point the TDA2050 went into oscillation in a bad way.
I would replace that .22 cap along with the new TDA & the 1 ohm R.
While you are in there , resolder the board.
Look for stupid assembler stuff like bent over component leads into an adjacent copper trace.
If you see that, soften the solder & lift the lead up off of the copper trace.
Pay attention to the big stuff when resoldering.
Capacitors & headers for sure.

[JoeM]

Thanks for the advice. I'll order the parts and check the items you mention.