The No.1 Website for Pro Audio
 Search This Thread  Search This Forum  Search Reviews  Search Gear Database  Search Gear for sale  Search Gearslutz Go Advanced
Trident Series 65 dead channel
Old 1 week ago
  #1
Gear Nut
 

Thread Starter
Trident Series 65 dead channel

I have 1 channel on my series 65 that seems unable to pass signal. I swapped it with a working channel and still nothing although the working channel did work in its place so I know the slot in the console is good. From a visual inspection nothing looks blown. I replaced all the chips just cuz I had a bunch of extra ones. I tested the pad and it seemed to be working correctly. Now that I think about it I actually forgot to test the mic/line switch. I'll test that in the morning. I also tested the input pot and the readings were similar to the working channel. It's not showing a clip light or anything when passing signal. I guess I could also check for signal from the insert to see if I'm even getting signal to there. Any other ideas or experiences that could point me in the right direction here? I've attached the schematic of the input section.
Attached Thumbnails
Trident Series 65 dead channel-20180611_221318.jpg  
Old 1 week ago
  #2
Lives for gear
 
SP2016's Avatar
Clean the contacts of the insert jack.
Old 1 week ago
  #3
Gear Nut
 

Thread Starter
I know it's definitely not that because I swapped the channel into that slot in the console and it worked fine. The inserts on this board are on the console and not the channel.
Old 1 week ago
  #4
Gear Nut
 

Thread Starter
That does give me an idea though. If I take the Sun from another Channel throw it to the return of the Dead channel and bypass the input stage maybe that will tell me if my faults is before the insert.
Old 1 week ago
  #5
Lives for gear
 
SP2016's Avatar
Check the orange/red "tear drop" tantalum capacitors (if any on that input channel)
Check for "cold" soldering joints

Last edited by SP2016; 1 week ago at 08:04 AM..
Old 1 week ago
  #6
Lives for gear
 
crosscutred's Avatar
Quote:
Originally Posted by Buffstuffbuddha View Post
That does give me an idea though. If I take the Sun from another Channel throw it to the return of the Dead channel and bypass the input stage maybe that will tell me if my faults is before the insert.
You can of course do this the other way round to see if the fault is after the insert.

You can also try bypassing eqs or switching sends in and out to troubleshoot switches (if the channel works when the eq is on but not when it is off, the problem is most likely the switch)

If you get into the habit of only testing the modules you want to trouble shoot things become faster, for example, instead of sending a signal into the channel you want to test and then through a group and the master to hear it you should be able to patch the output of that channel directly into the monitor input (or at least a known working channel running at unity, this can also be done with half the channel - pre or post insert.
This way you can isolate any problem quickly and confidently and come up with a work around and ultimately fix it.

The principle is the same at component level you just need probes to tap into the different stages and work out how to run the channel with access to the circuit board (this is what extender cards/cables are for)

Sorry if this sounds patronising, it's not intended that way, a basic understanding of troubleshooting is incredibly useful and even if you know all this there may be others it helps.

Good luck.
Old 1 week ago
  #7
Gear Nut
 

Thread Starter
That's basically the gameplan. I'm going to try to get to that tonight. As far as the switches, doesn't work with any of the switches in or out cuz I tried all of them. It's not even getting to a point where it shows the clip light on the channel. That's why I'm thinking it's either a cold solder joint or an actual bad component.
Old 1 week ago
  #8
Lives for gear
 
crosscutred's Avatar
Quote:
Originally Posted by Buffstuffbuddha View Post
That's basically the gameplan. I'm going to try to get to that tonight. As far as the switches, doesn't work with any of the switches in or out cuz I tried all of them. It's not even getting to a point where it shows the clip light on the channel. That's why I'm thinking it's either a cold solder joint or an actual bad component.
Of course the clip light led may be blown as well as something else in another part of the circuit which is what stops the audio working, don't make any assumptions.
Test the channel insert return.
Check the channel strip power rails, you will need to have it on extenders to do that.
Old 1 week ago
  #9
Trident 65/24 do not use the typical 10 ohm "fusing" resistors on the power rails like most other consoles. Therefore, if an opamp goes bad you may not see anything. They are socketed so swapping them is the way to determine if there is a failed 071 opamp.
Old 1 week ago
  #10
Lives for gear
 
SP2016's Avatar
Quote:
Originally Posted by Jim Williams View Post
Therefore, if an opamp goes bad you may not see anything. They are socketed so swapping them is the way to determine if there is a failed 071 opamp.
In the first post he already mentioned that he had replaced all op-amps in that channel module.
He did not make clear if he has tried the 'non working' module on another position in the console.
Old 1 week ago
  #11
Gear Nut
 

Thread Starter
I have tried it in another position on the console and still nothing. I also tried a working channel in the position the dead channel was originally in and everything worked.
Old 1 week ago
  #12
Lives for gear
 
SP2016's Avatar
That reduces the area of interest to the module itself.
Inspect the module for cold soldering joints.
Do the electrolytic capacitors look o.k. ? No signs of leaking ? No physical deformation ? Check the soldering of wire links.
Old 1 week ago
  #13
Gear Nut
 

Thread Starter
All the electrolytics look good and were replaced probably about 6 years ago. There really isn't anything on the board that visually seems off.
Old 1 week ago
  #14
Lives for gear
 
SP2016's Avatar
Did you check the three electrolytic power supply capacitors ?
Also check the 'auto mute' switch.
Attached Thumbnails
Trident Series 65 dead channel-trident-65.png  

Last edited by SP2016; 1 week ago at 10:40 PM.. Reason: addition
Old 1 week ago
  #15
Gear Nut
 

Thread Starter
There's actually only 2 electrolytics there. C45 is a ceramic disc. I tested both of those with my multimeter and they appear to be in working order. Same with the auto mute switch. I also tried the send from the bad channel to another channel and nothing. Then tried the send from a good channel to the return on the bad channel and nothing. Also tried every variation of the above with sends, returns, direct outs and line in and still nothing. This thing is just dead in the water. I really need to test it while it's running but I don't have extenders at the moment.
Old 1 week ago
  #16
Lives for gear
 
SP2016's Avatar
According to the schematics C45 is an electrolytic capacitor, indicating a + and - side.
A ceramic disc is not polarized.
Must be something wrong with the schematics as the part list indeed shows a 0.1 uF ceramic disc.

You have changed IC10 and IC11, but did you also change the multiplexer IC12 (14053) ??
These IC10, 11and 12 are the only ic's in the signal path from the insert return to the output.
(You already checked that you have no output sending a signal from the insert return.)
For the rest there are only the switches.
Do the led's function (eq, solo, mute) ?
Old 1 week ago
  #17
Gear Nut
 

Thread Starter
Ya the schematics show it as an electrolytic but even in the component list in the manual it's listed as ceramic disc. Ya, I swapped IC 12 with one from a working channel. All the led's work. Even if install the channel while the board is on the clip light flashes (just like if I did this with any channel) so I know that led works as well. Plus I tested them all with my multimeter. I even tested the transistors in the beginning of the channel with my multimeter and they appeared to be fine as well. I think I only tested q1 and q2 tho. I can't remember because I was getting burned out at that point.
Old 1 week ago
  #18
Gear Nut
 

Thread Starter
If I was to run a signal generator through this and check it with an O scope, where should I start?
Old 1 week ago
  #19
Lives for gear
Quote:
Originally Posted by Buffstuffbuddha View Post
If I was to run a signal generator through this and check it with an O scope, where should I start?
You start at the beginning, the input. Trace the signal through each circuit.

But first, make sure the + and - supply voltages are there.

The input signal hits Q1-4 before the first opamp. Your problem could be there.

My approach to troubleshooting a problem like this is:
1. Check supply voltages to opamps, etc.
2. Input simple tone to input of circuit and trace through to find the circuit that is not passing the signal.
3. Troubleshoot the circuit that is not working.
Old 1 week ago
  #20
Lives for gear
 
SP2016's Avatar
Quote:
Originally Posted by Buffstuffbuddha View Post
All the led's work. Even if install the channel while the board is on the clip light flashes (just like if I did this with any channel)
Installing a module while the console is powered on is a bad habit !!
There are lots of consoles where modules can be damaged when doing that.
Only a few manufacturers use some kind of buffering in the power supply rails to make it possibel to do 'live' module replacments.
Maybe I am 'old school', but I always switched, and still switch, consoles off before pulling or replacing modules.
Old 1 week ago
  #21
Gear Nut
 

Thread Starter
Ya, I know it's not the best practice but I I've been doing it for a while with this console. When I first got it I had to do a ton of work with it while it was on so I kind of just got used to hot swapping. I know that doesn't make it right haha.
Old 6 days ago
  #22
Lives for gear
 
Radardoug's Avatar
 

Some opamps do not like power supply line surprises (5534, 5532). With a bipolar supply, do NOT hot plug in. Pulling out is OK.
Listen, if you are serious about this console, then you need to get the tools to work on it. Dont muck around. Make/get an extender or a rig you can use on the bench. You will save so much time. The bench rig is preferable, and is usually just one pcb socket.
Topic:
Post Reply

Welcome to the Gearslutz Pro Audio Community!

Registration benefits include:
  • The ability to reply to and create new discussions
  • Access to members-only giveaways & competitions
  • Interact with VIP industry experts in our guest Q&As
  • Access to members-only sub forum discussions
  • Access to members-only Chat Room
  • Get INSTANT ACCESS to the world's best private pro audio Classifieds for only USD $20/year
  • Promote your eBay auctions and Reverb.com listings for free
  • Remove this message!
You need an account to post a reply. Create a username and password below and an account will be created and your post entered.


 
 
Slide to join now Processing…
Thread Tools
Search this Thread
Search this Thread:

Advanced Search
Forum Jump
Forum Jump