Page 1 of 2 12 LastLast
Results 1 to 35 of 57
Like Tree4Likes

Thread: Crate GX-15R Schematic

  1. #1
    Junior Member
    Join Date
    Jun 2009
    Posts
    2

    Crate GX-15R Schematic

    Hello Everybody!

    Please excuse my bad english.

    It's my first time posting a thread. I started about three months ago in guitar amp repair, and must admit that I`ve been lucky fixing some simple issues - loose potentiometers, or dirty ones, broken circuit boards, loose cables, etc. - and also lucky about finding the schematics, but not this time. I have to repair a Crate GX-15R amp fallen from a closet 7' high on a concrete floor. Speaker winding broke and is being repaired at a specialized shop. But the amp doesn't work with a friend's replacement speaker. After a long web browsing I found that the old Crate site closed (SLM Electronics) so no schematics anymore.

    This is the only site I found where members share those, then can somebody send or post a circuit diagram of the already mentioned amp for me please?

    I know that I am just starting with this fix, but in trust of being supported by this high quality members of this forum.

    Thank you very much in advance.

  2. #2
    Senior Member Enzo's Avatar
    Join Date
    May 2006
    Location
    Lansing, Michigan, USA
    Posts
    28,024
    Crate and all the rest of SLM are part of Loud Technologies, and it is all alive and well.
    Attached Thumbnails Attached Thumbnails 24701c4.pdf   24701b4.pdf  
    Education is what you're left with after you have forgotten what you have learned.

  3. #3
    Junior Member
    Join Date
    Jun 2009
    Posts
    2

    Thumbs up Yeeeeeaaaaaaahhhhhhh!

    Schematics Received.
    Excellent for a good beginning!

    Thank you, very, very, much.

  4. #4
    Junior Member
    Join Date
    Apr 2010
    Posts
    1

    schematic

    man i need a schematic for crate gx 15. can you help me

  5. #5
    Senior Member Enzo's Avatar
    Join Date
    May 2006
    Location
    Lansing, Michigan, USA
    Posts
    28,024
    Did you look at the schematic I posted above? The GX15 and GX15R use the same board. Without a reverb, they sumply leave off the reverb parts.

    Does that match your amp?
    Education is what you're left with after you have forgotten what you have learned.

  6. #6
    Member
    Join Date
    Aug 2009
    Posts
    35
    Enzo,I also downloaded the schmatic for the crate GX15R,mine dosn't work either. It lights up but no sound,I took the guts out of the cab and looked it over. I can't seem to find anything wrong , burnt or broken,no loose wires, just no sound. I checked the speaker and it's ok.Any ideas. I'm not an amp repairman, just poking around. Thanks, TVJR.

  7. #7
    Member
    Join Date
    May 2017
    Location
    Port Orange Florida
    Posts
    97
    Hello ENZO,
    I tried to print the Schematic but the format was not decoded by Adobe Reader so I can't print it. Could you please decode it and send it to me jagora?

    Thanks
    Joe

  8. #8
    Member
    Join Date
    May 2017
    Location
    Port Orange Florida
    Posts
    97
    Hey TVjr

    I have the same problem now May 8th 2017, How did you fix it? I need help

    Thanks Joe (jagora)

  9. #9
    Senior Member
    Join Date
    Sep 2011
    Location
    Pace, FL
    Posts
    1,176
    Quote Originally Posted by jagora View Post
    Hello ENZO,
    I tried to print the Schematic but the format was not decoded by Adobe Reader so I can't print it. Could you please decode it and send it to me jagora?

    Thanks
    Joe
    there is no problem with the schematic printing.

    nosaj

  10. #10
    Member
    Join Date
    May 2017
    Location
    Port Orange Florida
    Posts
    97
    Hey,
    It's a great schematic image BUT I can't print it, when I go to print the image automatically wants to save. I already have it saved. Any idea why I can't print it?

  11. #11
    Supporting Member The Dude's Avatar
    Join Date
    May 2010
    Location
    Sioux Falls, SD
    Posts
    4,234
    I imagine, since you can open it, it's a hardware software problem on your end. Can you print other things on your printer? It could be any number of things- printer driver not installed, default printer not selected, etc., etc.
    DrGonz78 likes this.
    “Yeah, well, you know, that’s just, like, your opinion, man.”

  12. #12
    Senior Member Enzo's Avatar
    Join Date
    May 2006
    Location
    Lansing, Michigan, USA
    Posts
    28,024
    If you have it saved, can't you open it, then print it?
    Education is what you're left with after you have forgotten what you have learned.

  13. #13
    Member
    Join Date
    May 2017
    Location
    Port Orange Florida
    Posts
    97
    Yes my printer works fine, let me try one more time

  14. #14
    Member
    Join Date
    May 2017
    Location
    Port Orange Florida
    Posts
    97
    I tried it again but it's in a PRN extension not a PDF format, that's the problem

  15. #15
    Supporting Member The Dude's Avatar
    Join Date
    May 2010
    Location
    Sioux Falls, SD
    Posts
    4,234
    The schematic Enzo posted in post #2 is a .pdf file. You must not have saved it correctly. You usually get a .prn file when you save to some sort of software printer for future use or something of the sort. I'm thinking you are sending the schematic to a print file instead of a physical printer. Check to see that your actual physical printer is set as your default printer.
    DrGonz78 likes this.
    “Yeah, well, you know, that’s just, like, your opinion, man.”

  16. #16
    Member
    Join Date
    May 2017
    Location
    Port Orange Florida
    Posts
    97
    I will take a closer look and double check although my past experience with imaging and printing have been as follows: If you scan a document with a tabletop scanner, sometime it saves the image as a prn file.

    Joe

  17. #17
    Member
    Join Date
    May 2017
    Location
    Port Orange Florida
    Posts
    97
    I tried it again and my software is saving it as a PRN file because my version of adobe is not compatible with the thumb print

  18. #18
    Supporting Member The Dude's Avatar
    Join Date
    May 2010
    Location
    Sioux Falls, SD
    Posts
    4,234
    If that is indeed the case, although it seems odd, try this.

    1) Open the document on your computer and make it full screen.
    2) Hold down "Shift" and then hit "Print Scrn". It will copy whatever is on your desktop to the clipboard.
    3) Open a graphics program like Paint, Photoshop, or something like that and start a new document.
    4) Paste the clipboard to the new document (Ctrl+V), or right click then paste. You should see the document now as an image file.
    5) Print the image out of your graphics program.
    “Yeah, well, you know, that’s just, like, your opinion, man.”

  19. #19
    Member
    Join Date
    May 2017
    Location
    Port Orange Florida
    Posts
    97
    O.K. I'll try that but maybe it's getting late so I'll do it tomorrow.

    Thanks for all of the great knowledge

    Joe

  20. #20
    Member
    Join Date
    May 2017
    Location
    Port Orange Florida
    Posts
    97
    What is the IC chip called? The chip that is mounted on the Crate GX15R circuit board and cooled by a massive heat sink?

    Joe

  21. #21
    Supporting Member The Dude's Avatar
    Join Date
    May 2010
    Location
    Sioux Falls, SD
    Posts
    4,234
    It's a TDA2030H output IC.
    “Yeah, well, you know, that’s just, like, your opinion, man.”

  22. #22
    Member
    Join Date
    May 2017
    Location
    Port Orange Florida
    Posts
    97
    I have been looking for something like that but it seems to be discontinued, at least the TDA2030/A I took apart a small Fender Frontman amp and it has a similar IC chip but it has TDA2050 stamped on it. Could I recycle that one and use it in place of the TDA2030H? I am also wondering what the most practical method of removing the actual circuit board from the Chassis face plate in order to gain access to the opposite side of the board (required to unsolder bits and pieces) Any good ideas would be great because after I get the courage to try and fix this amp, I have even a more difficult task involving a small Marshall MG10 Amp.

    Thanks for all of the feedback and suggestions
    Joe

  23. #23
    Supporting Member The Dude's Avatar
    Join Date
    May 2010
    Location
    Sioux Falls, SD
    Posts
    4,234
    Yes, you can use TDA2050 in place of TDA2030. I don't recall how a GX-15R is assembled, but commonly you remove the knobs and nuts on the pots- probably some screws board to chassis and carefully pull the board away from the faceplate and tip it back. Take pictures first, in case something comes disconnected or you need to disconnect something to get it out. I almost never completely remove a board or unhook anything I don't have to- just what is necessary to get to the bottom side of the part.
    “Yeah, well, you know, that’s just, like, your opinion, man.”

  24. #24
    Senior Member Enzo's Avatar
    Join Date
    May 2006
    Location
    Lansing, Michigan, USA
    Posts
    28,024
    TDA2050 is just a heavier duty version of the TDA2030, it goes right in place of the 2030.
    Education is what you're left with after you have forgotten what you have learned.

  25. #25
    Member
    Join Date
    May 2017
    Location
    Port Orange Florida
    Posts
    97
    Thank You very much for this advice. Sorry about the extremely late response from last night. The one thing that scares me about these circuit boards is that some of the wires are not meant to be removed at all. Especially on the Marshall power supply. It looks like the wires are connected with some sort of sealant or epoxy. I suspect that the manufacturer does this on purpose to prevent DIY repairs? I really do appreciate the information you are giving me because now I've built my confidence level to 99.9% and am just about ready to do my first repair.


    Thanks Again
    Joe

  26. #26
    Member
    Join Date
    May 2017
    Location
    Port Orange Florida
    Posts
    97
    Thanks for the boost of hope and confidence.

    Good advice on taking pictures while disassembly in progress. I'll try to gain access to the opposite side of the circuit board terminals using your suggestion.

    Appreciate All
    Joe

  27. #27
    Senior Member Enzo's Avatar
    Join Date
    May 2006
    Location
    Lansing, Michigan, USA
    Posts
    28,024
    ANything glued inside an amp is to help prevent it shaking around from vibration and breaking off.
    Education is what you're left with after you have forgotten what you have learned.

  28. #28
    Member
    Join Date
    May 2017
    Location
    Port Orange Florida
    Posts
    97
    O.K. Then if you peel the glue away, will it expose the soldered joint?

    Joe

  29. #29
    Junior Member
    Join Date
    Aug 2017
    Posts
    13
    I'm hoping Enzo or The Dude will chime in on this one. I picked up a used GX15 for my 9 yr old son who is getting into guitar (I am tagging along too!). Plugged it in when I got home, and nothing. Pulled out the board, and started checking and ohm'ing everything out. It looks like the power supply is bad, as there is no voltage coming out of it. The switch tests fine, and has voltage going in, but nothing out. From looking at the schematics posted it looks to be a 14V DC transformer. Does anyone know where to find one of these? I've been searching and have found a couple that look like they might work, but want to be certain before spending any money, as this amp looks to be pretty cheap to pick up used, and don't want to spend too much money on it...

    Thanks!

  30. #30
    g1
    g1 is offline
    don't forget the joker g1's Avatar
    Join Date
    Feb 2010
    Location
    Canada, somewhere north of Fargo
    Posts
    8,702
    Transformers are not DC. Set your meter to AC volts to see what is coming out of the transformer.
    Certified Dotard

  31. #31
    Junior Member
    Join Date
    Aug 2017
    Posts
    13
    Quote Originally Posted by g1 View Post
    Transformers are not DC. Set your meter to AC volts to see what is coming out of the transformer.
    I will plug it back in, and give it a check. what should I expect to see 14VAC?

  32. #32
    g1
    g1 is offline
    don't forget the joker g1's Avatar
    Join Date
    Feb 2010
    Location
    Canada, somewhere north of Fargo
    Posts
    8,702
    Probably somewhere around 20VAC between the 2 red wires.
    Certified Dotard

  33. #33
    Junior Member
    Join Date
    Aug 2017
    Posts
    13
    Thanks g1. sure enough, I've got AC voltage across the two red wires. Sure glad I asked before I purchased anything. I'm no EE, and I don't know how much further I want to dig on this, there are just two diodes where it looks like they got hot on the ends, close to where the power comes in, but the rest of the board looks good, nothing looks burnt or bad at all. Any thoughts on what to measure or look at? I did measure across the IC chip mentioned above, and I have voltage across it as well.

  34. #34
    Senior Member
    Join Date
    Sep 2011
    Location
    Pace, FL
    Posts
    1,176
    Quote Originally Posted by chkline View Post
    Thanks g1. sure enough, I've got AC voltage across the two red wires. Sure glad I asked before I purchased anything. I'm no EE, and I don't know how much further I want to dig on this, there are just two diodes where it looks like they got hot on the ends, close to where the power comes in, but the rest of the board looks good, nothing looks burnt or bad at all. Any thoughts on what to measure or look at? I did measure across the IC chip mentioned above, and I have voltage across it as well.
    How about a picture of the board. A few cheaper amps I've worked on lately(Roland Micro cube being one) They are using these little fuses that look like a red cylinder.

    nosaj

  35. #35
    Member
    Join Date
    May 2017
    Location
    Port Orange Florida
    Posts
    97
    I had this same issue except the power light (LED) illuminates and nothing else. I finally got all of the parts through "Mammoth Electronics" but have to be in the mood to do delicate work like removing the actual circuit board from the chassis in order to remove and replace I.C. circuits with soldering technique.

    Joe

Page 1 of 2 12 LastLast

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Need schematic for Crate FXT120
    By fixitrightthefirsttime in forum Maintenance, Troubleshooting & Repair
    Replies: 12
    Last Post: 02-09-2015, 03:48 PM
  2. Crate VC-50H Schematic
    By maulertone in forum Schematic Requests
    Replies: 3
    Last Post: 04-29-2010, 04:41 PM
  3. Crate BV120H schematic please!
    By walthur in forum Schematic Requests
    Replies: 1
    Last Post: 04-23-2009, 12:58 AM
  4. Crate BV300H schematic??
    By scustom in forum Schematic Requests
    Replies: 4
    Last Post: 03-22-2009, 02:37 AM
  5. Crate schematic
    By Valvehead in forum Maintenance, Troubleshooting & Repair
    Replies: 1
    Last Post: 12-18-2007, 08:40 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •