Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Instruments and Amps Everything that makes music, Especially including instrument amps.

fender blues deluxe reissue stuck distorting
fender blues deluxe reissue stuck distorting
fender blues deluxe reissue stuck distorting 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
Reply
 
Thread Tools Search this Thread
Old 1st February 2020, 02:28 AM   #1
buildafriend is offline buildafriend  United States
diyAudio Member
 
Join Date: May 2010
Default fender blues deluxe reissue stuck distorting

hi,

I have a blues deluxe reissue that is stuck distorting

any guesses based on these measurements? all VDC unless noted. I'm also curious if the distortion is simply stuck on. i only hear one relay click

V1A
plate 197
grid 0
cathode 1.4
B
plate 194
grid 0
cathode 1.4
V2A
plate na
grid na
cathode na
B
plate 207
grid 14mV
cathode 1.2
V3A
plate 194
grid 18.9
cathode 28.7
B
plate 200
grid 19.5
cathode 28.6
V4A
plate 352
g1 0
g2 352
g3 -49VDC
cathode 3.6mV
V5A = same as V4A
plate
g1
g2
g3
cathode
  Reply With Quote
Old 1st February 2020, 09:43 AM   #2
JonSnell Electronic is offline JonSnell Electronic  United Kingdom
diyAudio Member
 
JonSnell Electronic's Avatar
 
Join Date: Dec 2012
Location: The Jurassic Coast, England. GB
There are two relays, both are controlled from the same point.
Check the relays are energizing at the same time. Check D18 is not lit when clean selected.
If it isn't the relay, check R11 and R16.
Try inputting a signal at J4, power amp in socket, is it a clean output?
__________________
Support for Fender, Marshall and all Valve Equipment; Audio Innovations, Audiorama FU29, Quad and Leak. www.jonsnell.co.uk
  Reply With Quote
Old 1st February 2020, 02:31 PM   #3
buildafriend is offline buildafriend  United States
diyAudio Member
 
Join Date: May 2010
D18 is not lit when clean is selected

I replaced the flyback diodes for both relays - even though both diodes tested as good before hand. Still, Im used to being able to hear both relays click just barely off time in these situations. I think I only hear one.

R16 and R11 while in circuit measure 100k ( well closer to 99k.. )
  Reply With Quote
Old 1st February 2020, 02:44 PM   #4
buildafriend is offline buildafriend  United States
diyAudio Member
 
Join Date: May 2010
Any idea what these mods are? The amp was purchased in 2011
Attached Images
File Type: jpg C8D77AB9-C776-443F-9D3F-F8C0D4F49378.jpg (189.3 KB, 35 views)
  Reply With Quote
Old 1st February 2020, 02:59 PM   #5
buildafriend is offline buildafriend  United States
diyAudio Member
 
Join Date: May 2010
-20dBu program material seems to break up too early. I can't inject beyond said signal level to J4 without undesirable distortion coming from the amp. It still gets loud, but it breaks up in an ugly way and too early. when I turn the level into J4 up beyond -20dBu it gets ugly.
  Reply With Quote
Old 7th February 2020, 05:15 AM   #6
nauta is offline nauta  Canada
diyAudio Member
 
Join Date: Sep 2017
Hi


Have you tried the amp with a guitar? Although the nominal level of guitar is -20dB, real guitars have much different signal output. Fender's schemo shows a tiny input signal with specified control settings and a specific output (not necessarily max out).


The switching should work and be obvious that is going from clean to dirty and back again. But... the switching is not simple. The two relays switch together but one is off and the other is on and they alternate. They are controlled by three opamps, so you have to use the schematic and go through the switching circuit measuring voltages. It is easy to see with just a DC volt meter what should be on or off. That is one nice thing about switching circuits is that the voltages are always at an extreme.
  Reply With Quote

Reply


fender blues deluxe reissue stuck distortingHide 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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Fender Blues Deluxe Power Transformer Specs? elno Instruments and Amps 1 30th October 2015 07:32 AM
5E3 Tweed Deluxe distorting problem Stickleback Instruments and Amps 9 26th March 2014 02:17 AM
Converting a blues deluxe reissue... apostlegato Instruments and Amps 10 1st April 2011 03:03 AM
Fender Blues Deluxe cab built HELP! chucknorris Swap Meet 0 7th September 2008 01:18 AM


New To Site? Need Help?

All times are GMT. The time now is 02:28 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
Copyright ©1999-2020 diyAudio
Wiki