MasonAtom
Well-known member
substitute said:
hmm... thanks for the idea, I can probably import that graphic into QCad which is what I use for all my layouts.
Mason
S800 Support Thread
- Thread starter mrphotodude
- Start date
Help Support GroupDIY Audio Forum:
hmm... thanks for the idea, I can probably import that graphic into QCad which is what I use for all my layouts.
Mason
Hi ,
I'm finishing mine , but I mesure 15VDC @ the led connector...Is this normal?Did you add a resistor on each board for each led?
(All IC installed)
Thanks.
EDIT : Led connected and then voltage droped to 3,25VDC...
Sorry!
I'm finishing mine , but I mesure 15VDC @ the led connector...Is this normal?Did you add a resistor on each board for each led?
(All IC installed)
Thanks.
EDIT : Led connected and then voltage droped to 3,25VDC...
Sorry!
Dr nEon
Well-known member
Hi all!
I've been testing a whole bunch of electro caps, mainly in positions which are obviously in the signal path. 22uFs at C1&2,C17 etc.. and C23/26 output 100uFs.. ...using sockets to try out all the brands I have kicking around.
I haven't bothered with the 22uFs in positions C15 and C16 yet. I'm not sure how much influence these have, sonically. I'm trying to understand the purpose of these two caps...are they decoupling?
I'd appreciate an education from someone who can read this circuit better than I!
BTW it IS a lovely eq!
cheers
nEon.
I've been testing a whole bunch of electro caps, mainly in positions which are obviously in the signal path. 22uFs at C1&2,C17 etc.. and C23/26 output 100uFs.. ...using sockets to try out all the brands I have kicking around.
I haven't bothered with the 22uFs in positions C15 and C16 yet. I'm not sure how much influence these have, sonically. I'm trying to understand the purpose of these two caps...are they decoupling?
I'd appreciate an education from someone who can read this circuit better than I!
BTW it IS a lovely eq!
cheers
nEon.
Dr nEon
Well-known member
..any thoughts on this one , anyone ??
what are C15 and C16 doing?
many thanks in advance
nEOn.
what are C15 and C16 doing?
many thanks in advance
nEOn.
peterc
Well-known member
PSU decoupling.
Regards
Peter
Regards
Peter
Dr nEon
Well-known member
Cheers Peter!!
OK so I was along the right lines... must be learning!
I'll just leave the pana Fcs in place then, at those spots... I've found elna's to be my most preferred cap in the signal path places which I mentioned , but I assume that there's no point comparing anything in the psu decoupling positions, as the Fcs a decent cap anyway..
Big thanks , Peter , and well done on this lovely pcb!
nEon.
OK so I was along the right lines... must be learning!
I'll just leave the pana Fcs in place then, at those spots... I've found elna's to be my most preferred cap in the signal path places which I mentioned , but I assume that there's no point comparing anything in the psu decoupling positions, as the Fcs a decent cap anyway..
Big thanks , Peter , and well done on this lovely pcb!
nEon.
Hi...
I have a problem with 4 of my 8 boards...I checked every solder & resistor twice...The Only difference I noticed is :
-I used 220µF 35V instead of 50V (CPSU & CPSU1)
-I used 470µF 35V instead of 16V (C3 & C4)
The issue is that I can meter -12V@ pins of DIP8 (15v & -15V are well @ pins 4 & 8 -5532- and pins 4 & 7 -TL071-)
As the problem is the same with four boards , I fear a repetited error.
Does someone have a idea where to look at?
Edit : I use Collins kit , but Electrocaps have been replaced by Panasonics.
I have a problem with 4 of my 8 boards...I checked every solder & resistor twice...The Only difference I noticed is :
-I used 220µF 35V instead of 50V (CPSU & CPSU1)
-I used 470µF 35V instead of 16V (C3 & C4)
The issue is that I can meter -12V@ pins of DIP8 (15v & -15V are well @ pins 4 & 8 -5532- and pins 4 & 7 -TL071-)
As the problem is the same with four boards , I fear a repetited error.
Does someone have a idea where to look at?
Edit : I use Collins kit , but Electrocaps have been replaced by Panasonics.
sysexguy
Well-known member
Hi, just got a partially done unit (8ch) off the board and I'm working on a plan. I think I may have an elegant way to minimize the headaches of completing this build. If anyone has some comments or sees something I missed, please speak up
I've taken 8 of the mono (single gang) pots and ground down the lugs so that they can be inserted all the way into the pcb. The center pot of each strip (Lmid-level) lines up with the chassis holes. By grinding down the lugs I get enough clearance for the adjacent freq pots and (just barely) enough room to clear the mounting screws on one side. I will have to grind down 2 of the base screws (all unused) to align the cards vertically but that's easy. The remaining pots must have flying leads but this way, they are short and sweet.
I also thinking I should go for a relay bypass board mounted between the db25s. This would mean only needing 9 wires running to the front panel as the led and the switch can share the same wires and the 3pdt can be replaced with a spst. The bypass on the pcb would then be jumpered to the on position.
The front panel Led particularly the overall power led will be glued to the front panel (as it falls smack right where a pcb goes). I'm thinking I may just want to give a little extra space for those leds to be clean (and not shorting). Instead of mounting the front panel to the sides then a spacer and the mounting panel with a nut behind, I'd put the mounting panel in front of the sides.
I'll then have lots of room to deal with the psu.
The boards can then be secured with spacers and a long threaded rod.
TIA, Andy
I've taken 8 of the mono (single gang) pots and ground down the lugs so that they can be inserted all the way into the pcb. The center pot of each strip (Lmid-level) lines up with the chassis holes. By grinding down the lugs I get enough clearance for the adjacent freq pots and (just barely) enough room to clear the mounting screws on one side. I will have to grind down 2 of the base screws (all unused) to align the cards vertically but that's easy. The remaining pots must have flying leads but this way, they are short and sweet.
I also thinking I should go for a relay bypass board mounted between the db25s. This would mean only needing 9 wires running to the front panel as the led and the switch can share the same wires and the 3pdt can be replaced with a spst. The bypass on the pcb would then be jumpered to the on position.
The front panel Led particularly the overall power led will be glued to the front panel (as it falls smack right where a pcb goes). I'm thinking I may just want to give a little extra space for those leds to be clean (and not shorting). Instead of mounting the front panel to the sides then a spacer and the mounting panel with a nut behind, I'd put the mounting panel in front of the sides.
I'll then have lots of room to deal with the psu.
The boards can then be secured with spacers and a long threaded rod.
TIA, Andy
sysexguy
Well-known member
I'm wiring the same switch myself as we speak + Mouser's now ships free to Canada for orders over $200 which applies for this project's switches. (came in 24 hours wow!)
Andy
Andy
sysexguy
Well-known member
Hi, I've now wired up one channel for my first tests and when all the pots are centered and the hi pass is off, the sound is significantly darker that bypass. All bands and switches are working and I'm digging the action in the LF and LMF. Noise is very good as well and I haven't bumped the psu up to 18 yet (we're at +-15 stock green psu).
Any ideas what I may need to look at or is that kinda normal as the center detent is a mechanical approximation of 0 boost/cut?
very excited now!!!!!!
TIA,
Andy
Any ideas what I may need to look at or is that kinda normal as the center detent is a mechanical approximation of 0 boost/cut?
very excited now!!!!!!
TIA,
Andy
sysexguy
Well-known member
more tests, the dip is in particular between 2k and 6k
Andy
Andy
3nity
Well-known member
on the board there are small jumpers make sure you dont forget them!
but check carefully as theres a tiny one!!
but check carefully as theres a tiny one!!
sysexguy
Well-known member
Hi Jorge, tiny one tucked under U3? got it....so you're saying my observations are abnormal for this project? I need to keep searching....sometimes it's easier to troubleshoot when the whole shebang doesn't work at all....but it's more fun when audio passes and all the controls work but....
Andy
Andy
3nity
Well-known member
but you said you have 8 boards?
check another 1...
check another 1...
3nity
Well-known member
For schematics look into the G-mail account and search on it!
Thanks
Thanks
sysexguy
Well-known member
Yup already have the schematics, I wanted to get one installed before I paint myself in a corner building the "ship in the bottle"....trying another is a good plan, thanks
Andy
Andy
sysexguy
Well-known member
mybad :
shouldn't have been a hotdogger..... pulled the OPA's and put in trusty tl071's and presto works perfect.
Now, gotta find out why.....the green psu isn't big enough for a rack full of 8 ch's with opa's by a long shot but I thought I could power one channel for testing purposes.....I guess that's a probable cause. Any other ideas?
Btw, for future builders, r43 appears twice on the schematic, the 47k resistor marked r43 connected to pin 2 of u3 is r46
Thanks,
Andy
shouldn't have been a hotdogger..... pulled the OPA's and put in trusty tl071's and presto works perfect.Now, gotta find out why.....the green psu isn't big enough for a rack full of 8 ch's with opa's by a long shot but I thought I could power one channel for testing purposes.....I guess that's a probable cause. Any other ideas?
Btw, for future builders, r43 appears twice on the schematic, the 47k resistor marked r43 connected to pin 2 of u3 is r46
Thanks,
Andy
