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Problem with my SPX90
Old 23rd May 2019
  #151
Quote:
Originally Posted by madtheory View Post
Measuring the voltage with a DMM won't show you the ripple, which is caused by a failed cap and is the most likely (but not the only possible) cause of the fault in your unit. So even though your 5V seems "nice" on the DMM, it ain't necessarily so. Check the schematic, get a 'scope (they're fun and you only need 15MHZ for vintage audio gear, those are cheap).
Thanks. Wouldn't the lack of any -18v also be the first concern to fix?
Old 23rd May 2019
  #152
You're welcome. And yes, of course. All caps etc.
Old 23rd May 2019
  #153
Quote:
Originally Posted by madtheory View Post
You're welcome. And yes, of course. All caps etc.
Ok will do this last 2200uf but the rest are all changed. I didn't see the -18 going through the 2200 but will check again.
Old 23rd May 2019
  #154
Quote:
Originally Posted by Jesse Skeens View Post
Ok will do this last 2200uf but the rest are all changed. I didn't see the -18 going through the 2200 but will check again.
I didn't see either because I didn't check the schematic . So maybe a resistor has failed now as well? That would be kinda typical cause of no volt, other than the cap. But there are many causes. Again, I think Leeyoo's post was very clear on failure modes and probabilities.
Old 23rd May 2019
  #155
Quote:
Originally Posted by madtheory View Post
I didn't see either because I didn't check the schematic . So maybe a resistor has failed now as well? That would be kinda typical cause of no volt, other than the cap. But there are many causes. Again, I think Leeyoo's post was very clear on failure modes and probabilities.
I'm thinking something failed as when I first powered it on after installing the new R18 and one of the caps (forget now) there was a brief flash of light on the LCD. Now it just flashes very dim.

Either that or the new cap/resistor somehow changed the old equilibrium that was allowing the LCD to light up fully (although not sure if that would even make sense).

Will change the inductors as well for good measure. What would cause the green corrosion under those?

Will have another read of that post
Old 23rd May 2019
  #156
Gear Maniac
You might not need to change the inductors but you can remove and measure them with any cheap LCR Tester. They could easily be operating out of range sitting in that stuff on the board. Plus then you'll be motivated to clean the board. Sorry madtheory for bring it up over and over but the board has a combination of bad things on it. Two caps have leaked obviously and I'm sure you'll agree that everything they have leaked on needs to be cleaned and checked. And then there's my recommendation to remove the glue while at it.
Old 23rd May 2019
  #157
Quote:
Originally Posted by grantb3 View Post
You might not need to change the inductors but you can remove and measure them with any cheap LCR Tester. They could easily be operating out of range sitting in that stuff on the board. Plus then you'll be motivated to clean the board. Sorry madtheory for bring it up over and over but the board has a combination of bad things on it. Two caps have leaked obviously and I'm sure you'll agree that everything they have leaked on needs to be cleaned and checked. And then there's my recommendation to remove the glue while at it.
I ended up cleaning off most of the gunk now just so I could at least see the state of some of the components still on there (and read the markings of the board). So at this point it's relatively free of that.

There's a video of a SPX90 repair on Youtube that says that stuff can get conductive. I have no idea either way.

As far as the conductors it seems cheaper to just replace them as I don't think my meter does inductance. At this point I might as well rebuild as much as I can while I'm at it.

The unit was purchased from someone who used it in a radio station in Denmark, maybe it was close to the sea
Old 23rd May 2019
  #158
Quote:
Originally Posted by grantb3 View Post
Two caps have leaked obviously and I'm sure you'll agree that everything they have leaked on needs to be cleaned and checked.
Yes, agree there. I've said it already.

But the "gunk" (i.e. glue), no. And it's important to re-glue the replaced caps, or else they will fail sooner due to oscillation/ vibration.

Anyway, this is way too much talking. Go fix it! I got mine done in under 30 mins and it's been happy for 2 years now.
Old 9th March 2020
  #159
Gear Head
 

Is anyone able to help me identify a few parts I need to restore my SPX90? I can't make any sense of the parts list in the user manual.

Currently need an ID on D6, D7, L4, L5, L6 on the PSU card (VA81410), and the regulators on the AD card.

Cheers!
Old 15th March 2020
  #160
Gear Head
 

Anyone?
Old 16th March 2020
  #161
Maybe a stupid question but have you tried the parts list at the back of the service manual?
https://www.synthxl.com/wp-content/u...ice-Manual.pdf
Old 16th March 2020
  #162
Gear Head
 

Quote:
Originally Posted by madtheory View Post
Maybe a stupid question but have you tried the parts list at the back of the service manual?
https://www.synthxl.com/wp-content/u...ice-Manual.pdf
I did, yes but the part reference column is empty. Fortunately someone has pointed me in the direction of the Rev7 service manual - which shares the same power supply - so I've been able to deduce the part reference from that manual instead. :D
Old 16th March 2020
  #163
Quote:
Originally Posted by MrMesh View Post
I did, yes but the part reference column is empty. Fortunately someone has pointed me in the direction of the Rev7 service manual - which shares the same power supply - so I've been able to deduce the part reference from that manual instead. :D
Great news! I didn't even look at that page, as I didn't have your motivation lol.

Of course, it'll only make you want a REV7 now
Old 17th March 2020
  #164
Gear Maniac
Quote:
Originally Posted by MrMesh View Post
Fortunately someone has pointed me in the direction of the Rev7 service manual - which shares the same power supply
Wow good to know!
Old 3rd June 2020
  #165
Here for the gear
 

So I’ve recently replaced all the electrolytics and R18 in my SPX90 and it powers on although the LCD displays weird symbols and no sound passes. I’ve checked and I’m receiving *roughly* 18 and 5 at cn3 and cn4 and no ICs feel hot to the touch. Has anyone else experienced this? Any ideas, I’m a little stumped.

Should also mention that the unit won’t enter test mode and the foot trigger button is always on. I can hypothetically scroll through presets and settings but the screen is all jibberish so I have no idea what I’m entering.

*EDIT* it is passing sound and effecting it properly, just the LCD is corrupted with weird symbols!

Last edited by mikewolfe; 3rd June 2020 at 09:34 PM.. Reason: Adding an update
Old 4th June 2020
  #166
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Radardoug's Avatar
 

Did you replace the battery and do a full reset?
Old 2nd July 2020
  #167
Here for the gear
 

Quote:
Originally Posted by Radardoug View Post
Did you replace the battery and do a full reset?
Haven’t replaced the battery (although it has the correct voltage). Can’t do a full reset because the foot trigger button isn’t responding, but it’s LED is always on. This is also true for the up bottom on the right.
Old 2nd August 2020
  #168
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ghostwriter's Avatar
I have a question:
Some people say C11 should be 68uF 400v others say it should be 150uF 200v
Which is correct? Or ideal, if both are acceptable.
Thanks
Old 2nd August 2020
  #169
Gear Maniac
 
analogguru's Avatar
 

Quote:
Originally Posted by ghostwriter View Post
Some people say C11 should be 68uF 400v others say it should be 150uF 200v
Which is correct? Or ideal, if both are acceptable.
68uF/400v is for 230V AC power lines (e.g. Europe) and 150uF/200v is for 120V AC power lines (e.g. US).
Old 2nd August 2020
  #170
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ghostwriter's Avatar
Quote:
Originally Posted by analogguru View Post
68uF/400v is for 230V AC power lines (e.g. Europe) and 150uF/200v is for 120V AC power lines (e.g. US).
Thank you so much for clearing that up for me.
Old 2nd August 2020
  #171
Gear Maniac
 

Quote:
Originally Posted by ghostwriter View Post
I have a question:
Some people say C11 should be 68uF 400v others say it should be 150uF 200v
Which is correct? Or ideal, if both are acceptable.
Thanks
Better to check which PSU version you have first.
Then on the Service manual there's schematics for all the different PSU versions.
Always Re-check cap values there
Old 2nd August 2020
  #172
Gear Maniac
 

Quote:
Originally Posted by mikewolfe View Post
*EDIT* it is passing sound and effecting it properly, just the LCD is corrupted with weird symbols!
If it passes audio and works fine maybe the problem in only in the LCD circuit.
Locate that circuit on the schematic, replace all the Electrolytic and Tantalum Caps in that circuit and then do voltage measurements in that area
Old 3rd August 2020
  #173
Here for the gear
 

Quote:
Originally Posted by iLCacciLLo View Post
If it passes audio and works fine maybe the problem in only in the LCD circuit.
Locate that circuit on the schematic, replace all the Electrolytic and Tantalum Caps in that circuit and then do voltage measurements in that area
It’s also that the foot trigger and one up button aren’t responding properly, which seems completely random to me.
Old 3rd August 2020
  #174
Gear Maniac
 

Quote:
Originally Posted by mikewolfe View Post
It’s also that the foot trigger and one up button aren’t responding properly, which seems completely random to me.
The "Up Button" can be a bad switch... you could try to short the contacts (solder pads) directly to see if the function still works. if it works it's a faulty switch

Are the switches and the LCD on the same PCB?
And the foot switch input jack is it on the same pcb?
Old 3rd August 2020
  #175
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ghostwriter's Avatar
Quote:
Originally Posted by iLCacciLLo View Post
Better to check which PSU version you have first.
Then on the Service manual there's schematics for all the different PSU versions.
Always Re-check cap values there
Yes, thanks!
Old 3rd August 2020
  #176
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ghostwriter's Avatar
On post #103 there is a DigiKey parts list. I changed the quantities for one unit.

Part #'s
qty. 2 493-1553-ND
qty. 2 493-1550-ND
qty. 1 493-1496-ND
qty. 1 493-1501-ND
qty. 1 P14476-ND
qty. 1 565-1438-ND

P14476-ND is a 22uF 10V cap. I don’t see that in the power supply section.
Anyone know why that would be in the power supply caps parts list?

Thanks. Great thread.
Old 3rd August 2020
  #177
Gear Maniac
 

Quote:
Originally Posted by ghostwriter View Post
On post #103
P14476-ND is a 22uF 10V cap. I don’t see that in the power supply section.
Anyone know why that would be in the power supply caps parts list?
Is it in the schematics?

As far as I remember theres 4 different PSU versions.

Japan, USA, Europe and Canada.
Old 3rd August 2020
  #178
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ghostwriter's Avatar
Quote:
Originally Posted by iLCacciLLo View Post
Is it in the schematics?

As far as I remember theres 4 different PSU versions.

Japan, USA, Europe and Canada.
Okay, there it is on the schematic: C30

Thanks again.

Last edited by ghostwriter; 4th August 2020 at 03:25 AM..
Old 7th August 2020
  #179
Here for the gear
 

After re-capping my SPX90, I still get the same symptoms - tripping relays, flashing garbage on LED and LCD:

https://youtu.be/ICZGdOgd-34
Old 7th August 2020
  #180
Quote:
Originally Posted by urban_paranoia View Post
After re-capping my SPX90, I still get the same symptoms - tripping relays, flashing garbage on LED and LCD:

https://youtu.be/ICZGdOgd-34
What do the rails measure?
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