Problem with Yamaha RA-200 amp! Please help! - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Solid State Talk all about solid state amplification.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Thread Tools Search this Thread
Old 13th September 2012, 03:03 AM   #1
diyAudio Member
Join Date: Sep 2012
Default Problem with Yamaha RA-200 amp! Please help!

Hi everybody. I recently bought a vintage Yamaha RA-200 from a guy, he said its about early to mid 70's. This amp actually has 3 amplifiers. 1 for rotating speakers, and two for the top and bottom half of the 4x12s. Now the problem is that in one of the amps for the 4x12, one transistor (2SC783) started getting really hot and the sound started distorting. Now I have no idea what the problem is, and I want to get it fixed. I checked the resistors going to the base, and they are good. I also checked the power transistors TR6 and TR7, and they are working fine, so I don't know what else could be the problem. Thanks for any help!

The transistor is labeled TR4 on the schematic.
Attached Images
File Type: jpg yamaha_ra100.jpg (802.4 KB, 32 views)
  Reply With Quote
Old 13th September 2012, 05:31 AM   #2
Enzo is offline Enzo  United States
diyAudio Member
Join Date: Sep 2004
Location: Lansing, Michigan
This is an instrumemt amp, not a hifi amp, so they may move this to the proper section of the forum. So look down there if it disappears up here.

I saw this over at SSGuitar first, and responded there.
  Reply With Quote


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Yamaha RX-V490 Amp Problem har2k Solid State 22 26th January 2012 11:57 PM
Yamaha RA-70R Power amp schematic jasonm Instruments and Amps 0 31st July 2010 06:59 AM
Rotel RA-931 problem njholland Solid State 3 16th July 2006 04:01 PM
500w yamaha amp for sale $200!!! priscared Swap Meet 1 19th March 2004 11:58 AM
Yamaha NS-200 mod/upgrade suggestions needed. GregGC Multi-Way 17 17th February 2004 02:04 AM

New To Site? Need Help?

All times are GMT. The time now is 02:33 AM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright ©1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2