The effects do not work on my Crate VTX 350 H, what's wrong with it?

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If sure that power is reaching and getting into unit, then confirm that a signal is also reaching unit. If both are positive, then your gear is FUBAR if signal is going into correct input.

Check your guitar with another amp, or a different guitar with this one with no effects pedals, etc, to narrow it down to just the amp. At that point, try reversing the polarity. If none of the above helps, you may indeed have a bad ground somewhere and you'll need a tech to follow it to the source.

On some amps there needs to be a footswitch inserted in the control jack to activate the effects circuit. Contact Crate to see if that's the case with your amp.
http://www.crateamps.com/support/index.php

sure, why not, the footswitch connects between the guitar and the amp, with your guitar into the footswitch, go rock that thing!

That is probably a momentary switch that is dirty and sticking. These onboard effects on guitar amps are usually nothing more than a computer sound card and I've found bad connections going to and from them as well. I do think that switch is dirty and sticking, though.

Hi there,I have the same problem with my flexwave 120. I opened the amp to measure several capacitors on the small effect circuit board. If one of this capaciters have internal short circuit, wich will effect the others causing effects to fail. I removed them one by one to find possible short circuit. All capacitors were ok. I think the problem is in the processor wich is to diffucult to replace. I think it's easier to replace the effects circuit board. But where do we find this board??

I can understand your confusion... and a lot depends how you are going to use this. There are some caveats regarding the connections,
If you use the 1/4 outputs on the GSP, there is a speaker modeling like function that is NOT available, that IS available IF you use the XLR outputs.
The STP is an "Insert Snake" which is not really what you want as it is intended to send and receive (audio going both directions in the cable.
If you want that speaker function, then you should get two XLR to 1/4 TRS cables and go from the XLR's on the GSP to the Left and Right inputs on the back of the Crate. Your audio or guitar then is connected to the GSP guitar input.
If you connect the guitar to the crate and then use the STP, Plug the TRS single connector into the Left/Mono/send/rtn on the Crate. The Send cable of the Y should go to the Send jack on the back of the GSP and the return should go to the left return jack of the GSP. This connection I would NOT recommend as it will be noisier and you will lose the stereo effect capabiltiy since the effect is inserted as a mono.

I believe you would be happier with using the XLR's to carry left and right to the Crate and run your inout to the GSP. In short, you have the wrong cable to do the best job.

its a crate. 60% of all crate amplifiers go back on defects. take the top screws out and slide out the chasis, look at the fuse and determine if its toast. if the fuse is good, get a new amp. if the fuse is bad replace it and you should be good. the circuit board will have the correct fuse to be used printed on the board.
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