Hi Everyone
I'm looking for help and advice on repairing some old MTX 2300's. I haven't worked on amps before but I'd like to see if I could resurrect these amps. I'm going to be hooking them up and trying them to see what happens. It's been years since I've had them working so I can't remember what issues I had with them. Is there some threads or tutorials I can read to learn how to test the individual components in the amps like FETS etc.? I'd really like to learn how to do these repairs but if this stuff is over the head of the average Joe, is there someone that can repair these affordably? I'd hate to junk them because back in the day they hammered. I'm on permanent disability so I have plenty of time to learn and not much cash.
Thanks, Steve.
I'm looking for help and advice on repairing some old MTX 2300's. I haven't worked on amps before but I'd like to see if I could resurrect these amps. I'm going to be hooking them up and trying them to see what happens. It's been years since I've had them working so I can't remember what issues I had with them. Is there some threads or tutorials I can read to learn how to test the individual components in the amps like FETS etc.? I'd really like to learn how to do these repairs but if this stuff is over the head of the average Joe, is there someone that can repair these affordably? I'd hate to junk them because back in the day they hammered. I'm on permanent disability so I have plenty of time to learn and not much cash.
Thanks, Steve.
Thanks, Perry. I've already been reading all the threads on 2300's I can find. I really appreciate an expert taking the time to help a newbie. I have 4-2300's and 3-4320's so I have plenty to check. The two 2300's I bought of E-Bay need the most attention. Both boards are marked the same. TA2300 amplifier board - part MVP026 - REV D - ASSY NPA031. Both are dated 2-9-96. One has the RCA's broken off the board and the other has RECT.2 damaged. Can the RCA's be fixed? What soldering gun do you recommend for circuit board repairs? The gun I have is for bigger repairs.
Thanks, Steve.
Thanks, Steve.
I read the "Checking Field Effect Transistors" section and attempted to check FET's 1-20 not including RECT1 and RECT2. Here are some examples of the results I got:
Test 1 Test 2 Test 3 Test 4
FET1 1710 / 786 1860 open 545
FET5 1636 / 777 open open 525
FET10 530 / 22 022 1349 500
FET15 1650 / 784 1827 1827 507
FET20 1662 / 787 open open 510
I want to make sure I did it right. Because every FET had values in test 1 instead of being open, does that mean there all shot? Or did I do something wrong?
Test 1 Test 2 Test 3 Test 4
FET1 1710 / 786 1860 open 545
FET5 1636 / 777 open open 525
FET10 530 / 22 022 1349 500
FET15 1650 / 784 1827 1827 507
FET20 1662 / 787 open open 510
I want to make sure I did it right. Because every FET had values in test 1 instead of being open, does that mean there all shot? Or did I do something wrong?
Thanks Perry. I was wondering that. I figured it was unlikely that all the FET's were blown. I have to order the soldering gun before I can remove FET10.
In order to properly test the two amps, should I fix the broken off RCA's on the one and the blown RECT2 FET on the other first? Then try and power them up to do the tests you outlined in the tutorial to determine any other problems. If this is correct where can I order the RCA's from because the leads for mine are broken off at the board as well as the blown FET?
In order to properly test the two amps, should I fix the broken off RCA's on the one and the blown RECT2 FET on the other first? Then try and power them up to do the tests you outlined in the tutorial to determine any other problems. If this is correct where can I order the RCA's from because the leads for mine are broken off at the board as well as the blown FET?
Hi Perry
I know you prefer separate threads for each amp and in the future that is what I will do.
So to be clear, I would solder two small lengths of wire from the broken leads on the circuit board to the broken leads on the RCA's. It looks like someone did a bad job soldering the black wire on the side. Should I try and redo that connection as well? This is the only defect I can visually see on this amp. Once the RCA is temporarily fixed I will attempt to power it up. I will start a new thread describing any problems I find.
With the other 2300, RECT2 has all three leads severed along with one lead of FET12. Should I attempt to replace the FET12 and RECT2 before powering up? This amp also appears to have pop or some other brown sticky liquid on the spots of the board. What cleaning solution would be safe to use with Q-tips to clean the board?
I attached some pictures of the RCA's and the two damaged components on amp #2. I read your tutorial on how to take pictures so hopefully they're not to bad. before even trying to power it up.
I have to order the soldering gun, solder removal tool, etc. to begin the repairs. Being new to this is there a site where I can order new RCA's, FET12 and RECT2?
I know you prefer separate threads for each amp and in the future that is what I will do.
So to be clear, I would solder two small lengths of wire from the broken leads on the circuit board to the broken leads on the RCA's. It looks like someone did a bad job soldering the black wire on the side. Should I try and redo that connection as well? This is the only defect I can visually see on this amp. Once the RCA is temporarily fixed I will attempt to power it up. I will start a new thread describing any problems I find.
With the other 2300, RECT2 has all three leads severed along with one lead of FET12. Should I attempt to replace the FET12 and RECT2 before powering up? This amp also appears to have pop or some other brown sticky liquid on the spots of the board. What cleaning solution would be safe to use with Q-tips to clean the board?
I attached some pictures of the RCA's and the two damaged components on amp #2. I read your tutorial on how to take pictures so hopefully they're not to bad. before even trying to power it up.
I have to order the soldering gun, solder removal tool, etc. to begin the repairs. Being new to this is there a site where I can order new RCA's, FET12 and RECT2?
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RCAs:
Look at the way the wire is attached to the RCA in the photo I posted. That's what I'd suggest that you do for the ground. You'd, of course, solder the wire to the bottom of the RCA jack before installing it. If the other two are broken, solder a length of wire along the length of the metal on the jack and let it extend beyond the jack far enough to allow you to solder it into the board.
Rectifiers:
The amp will not work without the rectifier soldered into the circuit. The way the legs are broken, you can solder them back together. When you replace the rectifiers and FETs, bend the legs on a radius, not a sharp bend. This will make them less likely to fail. See attached.
FETs:
The power supply FETs appear to be blown. If so, they will need to be replaced before the amp will power up.
The FETs and rectifiers can be purchased from Digi-key or mouser (among others). I'd use the IRF3205 for the FETs. Order the MUR1620CT and MUR1620CTR for the rectifiers. I think the following RCA jack will work but the red and black are reversed.
Invalid Request
Look at the way the wire is attached to the RCA in the photo I posted. That's what I'd suggest that you do for the ground. You'd, of course, solder the wire to the bottom of the RCA jack before installing it. If the other two are broken, solder a length of wire along the length of the metal on the jack and let it extend beyond the jack far enough to allow you to solder it into the board.
Rectifiers:
The amp will not work without the rectifier soldered into the circuit. The way the legs are broken, you can solder them back together. When you replace the rectifiers and FETs, bend the legs on a radius, not a sharp bend. This will make them less likely to fail. See attached.
FETs:
The power supply FETs appear to be blown. If so, they will need to be replaced before the amp will power up.
The FETs and rectifiers can be purchased from Digi-key or mouser (among others). I'd use the IRF3205 for the FETs. Order the MUR1620CT and MUR1620CTR for the rectifiers. I think the following RCA jack will work but the red and black are reversed.
Invalid Request
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