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Author Topic: Crate GX-212  (Read 10175 times)

drumr

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Crate GX-212
« on: March 15, 2009, 05:23:25 AM »

Does anyone have a picture of a Crate GX-212 circuit board, wired? I am re-connecting my power leads and lost my own notes. (oops). Have just finished replacing various switches and re-soldering 8 broken or cold joints. Cannot find schematic on any sites. Cleaned up the jack connections and was ready to go. Wish me luck.
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J M Fahey

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Re: Crate GX-212
« Reply #1 on: March 15, 2009, 12:47:40 PM »

Hi Drumr. I don´t have it either, but if you only need to connect the 3 main secondary wires, it´s no that difficult. Probably they´re color-coded , probably two some color or color combination and the third another color ; for example, say, two red-orange and one black or blue or even plain red or something equivalent. The odd one should be center tap and goes to ground, check whick power pin on the board is  grounded, besides it also goes to the junction of the two big filter caps . You also have a big diode rectifier bridge, either discrete (4 diodes, generally coded as 2N54xx) or a "diode pack" which has 4 pins: + , - , AC , AC.
Those two wires go to AC and AC. Sometimes only a + sign is used, it´s assumed that the opposite it is - and the two others are AC and AC. Power the amp preferably hooked into a series lamp, just in case.
If in doubt post a picture showing the board terminals and the transformer wires close to them. I you disconnected the mains wires, sorry, can´t help you, it´s dangerous/deadly stuff, keep fishing for some schematic or ask Crate themselves. Bye.
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teemuk

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Re: Crate GX-212
« Reply #2 on: March 15, 2009, 12:59:18 PM »

Here.
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drumr

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Re: Crate GX-212
« Reply #3 on: March 15, 2009, 03:41:28 PM »

Thank you both so much. Those schematics are a bear to find! You guys made my day. I've been searching for 3 days to find this info. Will be looking for any schematics I have to help out this site. I've collected a few over the years. Also sorry,I think I posted on the wrong thread. :-\
« Last Edit: March 15, 2009, 03:43:27 PM by drumr »
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J M Fahey

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Re: Crate GX-212
« Reply #4 on: March 15, 2009, 06:59:48 PM »

Hi Drumr, glad you´ll now be able to fix it.
Please post the actual colors of the 3 secondary wires.
Dear Teemu, thanks again for your help. Your constant posting of needed and not easily found schematics is priceless.
Tnx.
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drumr

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Re: Crate GX-212
« Reply #5 on: March 15, 2009, 07:15:56 PM »

Here is a pic of how I thought it was wired. Haven't checked the schematic yet. Will post again if different.
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J M Fahey

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Re: Crate GX-212
« Reply #6 on: March 15, 2009, 07:45:57 PM »

Looks fine to me. As I guessed, the two red wires go to J26 and J28 (A.C. pins on the diode pack); and the green one to J27 who sits nicely between both big capacitors/filters and which must be a ground connection.
Can´t read the labels in the picture but the copper traces can be faintly seen going ftom the two red ones towards the AC pins . Anyway, if you want to play it real safe, hook it up first to a series lamp, just to beat "Murphy´s Law".
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drumr

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Re: Crate GX-212
« Reply #7 on: March 15, 2009, 08:02:49 PM »

Thanks again. She's purring like a kitten. J.M., you were right on the money. And teemuk, thanks again for the double-check.
     Hooked it up to a low-amp breaker just to be sure. I'll have to check my channel switch again. Won't change to lead channel. Cleaned the jacks and thought I soldered everything o.k.  Must have a cold joint on the switch. Have to be careful with these pads on this board. Not exactly like a Fender, haha.
     I picked this up for $30.00 at a garage sale last week. The guy said it was changing channels. Thought it was just a jack until I opened it up and found several wires disconnected. Thought I had a DOA. Turned out I had a bargain anyways. Case is clean and has original speakers. All in all, in very good shape. Tolex and grill cloth o.k. too. I'm a happy camper.
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stasisrant

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Re: Crate GX-212
« Reply #8 on: November 25, 2009, 08:53:49 PM »

Im new to the forum. I just found it searching for GX-212 schematics. I have read the sticky and I wont ask for anything in this thread, I just wanted to say thanks for making such an awesome site and thanks for the schem!
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