Home |
Search |
Today's Posts |
![]() |
|
Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems. |
Reply |
|
LinkBack | Thread Tools | Display Modes |
#1
![]()
Posted to sci.electronics.repair
|
|||
|
|||
![]() ########################################## This post is an informational post for anyone running in to the same problem with a Peavey VTX Classic guitar amp. From other post on the Internet it appears other people have had this problem from aging Peavey VTX Classic amps. ########################################## I have a Peavey VTX Classic guitar amp I purchased new back in 1983. It is a tube/solid state hybrid amp. The tube finals are 6l6gc tubes. The rest is solid state. One night while I was playing out the amp stopped working, and one of the 6l6gc tubes started glowing red. The tubes checked good in a tube checker with no shorts or leaks. The problem was traced back to a blown audio driver and pre-driver transistor. The audio driver transistor is marked "M 5884" with a Motorola "M" trademark. I searched the Internet and virtually no mention of this transistor. Eventually I found a cross reference replacement transistor called MJE15030. There is a vendor on Ebay selling the MJE15030 transistors. I imagine Peavey has them as well. The "M 5884" transistors are mounted against two large metal heat sinks. I replaced both of the "M 5884" transistors with the new MJE15030 transistors. The amp started putting out sound again and the one tube stopped glowing red, but the audio was fuzzy even in the clean channel. I contacted Peavey repair and they provided a schematic diagram for the Peavey VTX Classic free of charge. The repair person also recommended I replace the two driver transistors - MPS6530. The MPS6530 transistor cross references to transistor 2n3904. The 2n3904 transistor is available at Radio Shack for about 75 cents U.S. The MPS6530/2n3904 transistors are marked as Q4 and Q5 on the Peavey VTX Classic schematic. After replacing the two driver transistors MPS6530/2n3904 the old Peavey VTX Classic starting working normally and the unwanted distortion in the clean channel was gone. I contacted Peavey at the following email addresses to get the free schematic diagram and parts layout diagram. Thanks to Peavey.com Michael |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Forum | |||
Peavey VTX Classic guitar amp and the M 5884 audio chip. | Electronics Repair | |||
1WATT inexpensive tube guitar amp request | Electronic Schematics | |||
Luminglas stopped working | Electronics Repair | |||
TV stopped working plz help. | Electronics |