I was given this Crate amp and love the chorus, so creamy.
Unfortunately I originaly only got the bare chassis. I now have the rest but the reverb is disconnected.
I need to find which spade lugs to reconnect the reverb to.
I have seen photos online but all have been to blurred to tell which connection to use.
Unfortunately I originaly only got the bare chassis. I now have the rest but the reverb is disconnected.
I need to find which spade lugs to reconnect the reverb to.
I have seen photos online but all have been to blurred to tell which connection to use.
Look at board with controls to front. The four connectors are straight back from the GAIN and LOW controls. There are two ICs right next to each other. There is one pair of spades closer to the ICs, sort of a horizontal row of two, they are the SEND to the INPUT of the reverb pan. The left one is the hot, the ther one to the right is the cold side. Check that it is about 10 ohms above ground. It is not directly grounded, but that is the shield connection for the send cable.
The other two spades are in a row front to back and closer to the single IC on the right. They are the return and connect to the OUTPUT of the reverb pan. The one to the rear is ground - verify with an ohm meter - and connects the shield of the return cable. That leaves the other one, closer to the front, as the hot of the return cable.
In general, for most amps, you can tell. Turn the amp on with the reverb up part way. Now touch each spade with a small screwdriver or something. One will hum out the speaker. That will be the hot for the return. Another will be connected to ground - use an ohm meter - and will be the return shield. The other two will be drive. Some drives have a grounded side, easy enough to find. But a lot of solid state drives have the low side of the drive not ground, like this amp. So we measure the resistance to ground from each, the lower one will get the shield, and the one farther from ground will be the drive hot. That will solve most of them, though I am sure someone can find some exception.
The other two spades are in a row front to back and closer to the single IC on the right. They are the return and connect to the OUTPUT of the reverb pan. The one to the rear is ground - verify with an ohm meter - and connects the shield of the return cable. That leaves the other one, closer to the front, as the hot of the return cable.
In general, for most amps, you can tell. Turn the amp on with the reverb up part way. Now touch each spade with a small screwdriver or something. One will hum out the speaker. That will be the hot for the return. Another will be connected to ground - use an ohm meter - and will be the return shield. The other two will be drive. Some drives have a grounded side, easy enough to find. But a lot of solid state drives have the low side of the drive not ground, like this amp. So we measure the resistance to ground from each, the lower one will get the shield, and the one farther from ground will be the drive hot. That will solve most of them, though I am sure someone can find some exception.
Enzo
hooked up the reverb> was going to try something like that but didn't want to take chance getting send and return mixed up. Still no go. The transducers in the reverb box read 25ohm send side and 210 on the return.
Did the screwdriver trick on the return for hot.. nada not a peep that parrots dead.
Not sure about the foot switch but from what you said I think something else is pooched.
Do you know where I can find a schematic? I'll come back another day and give it a go. Without some help I will have to use it without reverb.
Thanks again
hooked up the reverb> was going to try something like that but didn't want to take chance getting send and return mixed up. Still no go. The transducers in the reverb box read 25ohm send side and 210 on the return.
Did the screwdriver trick on the return for hot.. nada not a peep that parrots dead.
Not sure about the foot switch but from what you said I think something else is pooched.
Do you know where I can find a schematic? I'll come back another day and give it a go. Without some help I will have to use it without reverb.
Thanks again
If you got them backwards, it wouldn;t hurt anything, just wouldn;t work either.
My schematic is four pages of 11x17, I got no way to scan them. Contact Loud technologies and ask if they can provide the drawings, they own Crate. Your amo is not on the master service disc that SLM used to put out, it is older, so they'd have to look in the older files.
My first suspect, after the pan is OK, is that IC6. The IC of the pair, on the right. The send posts are wired right to it. IC6 does both send and return.
My schematic is four pages of 11x17, I got no way to scan them. Contact Loud technologies and ask if they can provide the drawings, they own Crate. Your amo is not on the master service disc that SLM used to put out, it is older, so they'd have to look in the older files.
My first suspect, after the pan is OK, is that IC6. The IC of the pair, on the right. The send posts are wired right to it. IC6 does both send and return.
All looked good everywhere. Some pops and noise level whent up a bit now and then. There is an intermitent short and open circuit in the return line at the spade lugs. Checked and re checked before I put them in..when hel in hands there was good contact. Bad connection and bad (shorting to shield) cable. Replaced and all is good to go.
Lost chorus. Broke the one speaker wire. Repaired. Yahoo
This baby is old and abused. I hope its life is now restored and extended.
Thanks fo all the help and the schematic. Great for future trouble shooting.
Lost chorus. Broke the one speaker wire. Repaired. Yahoo
This baby is old and abused. I hope its life is now restored and extended.
Thanks fo all the help and the schematic. Great for future trouble shooting.
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