Soundtracs Solitaire Cap replacement

[abbey road d enfer]

Thanks again for your advice. I am looking for a second-hand cheap oscilloscope to buy.

A scope won't help you much here, except maybe in case of gross failure.
I would recommend you use a soundcard/converter with the REW software (free) and learn to visualize frequency response

 

[Joey777]

The software looks really good I have downloaded it and going to give it a whirl.
As for the scope I thought a cheap 50 / 100 euro scope would be handy to have. Seen an older dude in a video with something like a capacitor rigged up to a headphone to trace signal problems. When there was no signal the headphone didn't beep. Seemed to be finding out where the signal stopped and then guess which component was failing or failed.

Thanks for the REW tip

 

[Joey777]

I have tried sending an oscillator through the dodgy channels and I get signal on the monitor path but nothing on the line and the 24 buss's are good.

Tricky Stuff indeed

 

[Newmarket]

Reading this thread I can't help thinking that it has become a little over complicated for the OP's query ?
So - there are not "AC capacitors" and "DC Capacitors".
There are ratings for AC Voltage and DC Voltage that may be specified for any particular Capacitor.
6.3V - Do you mean 63V. 6.3V caps would only be suitable for something like a 5V Voltage rail (for digital logic supply) and even then it's cutting it a bit fine. 63V accommodates Phantom Power at
c. 48V. But I'd always suggest at least 100% overrating so a 100V cap.
For ac signal coupling caps the polarity and any issues around that are unlikely to be obvious - basically a few volts reverse polarity will be 'okay' (even if not optimum).
Physical Form - yes Axial is not so popular now but you might be able to bend the legs of Radial parts and push the cap down as / if required ?

 

[Joey777]

Hi Newmarket. Thanks very much for chipping in.
The console has 17.5v rail and a 5v rail. I think your right ( not that I am knowledgeable enough ) about the 5v rail as I guess it is for the onboard DSP dynamics.
When I was looking on Farnell.nl I seen 2 different choices for some caps at a certain voltage one said VDC and that threw me a bit.
The problem I have with the axial type caps is there are quite a few side by side and not alot of room to maneuver. I dont think height is a problem but having 4 caps tightly in a row is looking tight

Thanks ever so much for helping me out

 

[Seon]

Remind me when I refurbished an old SOLO MIDI a few years ago.
Tim from StudioSystem can be of a good help, especially if you need the schematics (and advices).
https://studiosystems.co.uk/technical_help/index.php
Soundtracs used plenty of non polarized caps (that look like light green resistances) outside the signal path.
I don’t think you have to worry about it in your case but does someone ever had to replace this kind of cap ?
Always wondered what to replace them with.

 

[abbey road d enfer]

Soundtracs used plenty of non polarized caps (that look like light green resistances) outside the signal path.
I don’t think you have to worry about it in your case but does someone ever had to replace this kind of cap ?
Always wondered what to replace them with.

After your description, they could be ceramic caps. They probably don't need to be replaced.

 

[Joey777]

Remind me when I refurbished an old SOLO MIDI a few years ago.
Tim from StudioSystem can be of a good help, especially if you need the schematics (and advices).
https://studiosystems.co.uk/technical_help/index.php
Soundtracs used plenty of non polarized caps (that look like light green resistances) outside the signal path.
I don’t think you have to worry about it in your case but does someone ever had to replace this kind of cap ?
Always wondered what to replace them with.

I bought the desk 10 or so years ago from Tim Jones.
He is a real gentleman. But Tim is in the UK and after the brexit nonsense it's a bit of an ordeal to send stuff for repair. I spoke with Tim recently and he has semi retired. He still works on the PSU " BlueDog " but doesn't do the servicing any more, someone else has taken that over, Nevil from Taunton.
Tim gave me a few things to check and after checking he advised to either get a Tech in ( I don't have the money for that ) or buy an oscilloscoop and learn to trace. I don't think Tim will give out the schematic for the Solitaire or the Jade as it could take work away from his company and that's understandable for me.
He did say that the electrolytic caps will probably be the fault. I seen a video of Tim using a cap joined to an old headphone to sniff out a bad signal.

 

[Joey777]

After your description, they could be ceramic caps. They probably don't need to be replaced.

There are a few of those resister looking caps there and also the flat square looking caps ( film caps maybe ) Tim also suggested that they would be fine as he has never had to replace any before. He did breathe a sigh of relief when I to him all the mutes were working fine.........in his own words, he said the Solitaire is a "Bitch" to work on. Said the mutes problem on the Solitaire was the worst ever

 

[Seon]

After your description, they could be ceramic caps. They probably don't need to be replaced.

Thank you !


Yes, Tim is really a very nice person.
At that time I paid for his “two years online tech support” and he provided me with all the schematics I needed. Even some of consoles I don’t own when I wanted to study a few other designs.

 

[Joey777]

I can always ask. Don't suppose there's any harm in asking, for the schematics. I also bought the 2 year support and a new BlueDog PSU, which really did make a difference to the sound I think.
My parts are ordered and on their way. If I can get the 4 dodgy channels back up and running, I will be chuffed to bits and shouting from the roof-tops.

 

[Ike Zimbel]

A few notes on cap failure: Typically for an electrolytic cap to have failed badly enough to stop ANY signal from passing, it needs to be dried up to the point where it is virtually empty. For example, in Neve V and VR desks that run really hot, it is not uncommon to remove 100uf caps that will read, maybe 0.1uf on a capacitance meter. On the other hand, caps that have lost even 50 -75% of their marked value will usually still pass signal, it may just sound like crap...no low end, no high end (due to very high ESR) and just generally mushy.
A few things I have noticed in handling totally dried out caps:
1) They heat up during re-work. So, for example if you have your finger on a cap, holding it in place while you de-solder it, your finger may get uncomfortably hot.
2) They feel lighter than an equivalent new cap.
3) They make a "tink-tink" sound when they are handled (like when you throw one on the pile of just removed caps).
All of the above are due to the loss of electrolyte, the fluid in the caps, which effectively makes them an empty aluminum can.

 

[Joey777]

A few notes on cap failure: Typically for an electrolytic cap to have failed badly enough to stop ANY signal from passing, it needs to be dried up to the point where it is virtually empty. For example, in Neve V and VR desks that run really hot, it is not uncommon to remove 100uf caps that will read, maybe 0.1uf on a capacitance meter. On the other hand, caps that have lost even 50 -75% of their marked value will usually still pass signal, it may just sound like crap...no low end, no high end (due to very high ESR) and just generally mushy.
A few things I have noticed in handling totally dried out caps:
1) They heat up during re-work. So, for example if you have your finger on a cap, holding it in place while you de-solder it, your finger may get uncomfortably hot.
2) They feel lighter than an equivalent new cap.
3) They make a "tink-tink" sound when they are handled (like when you throw one on the pile of just removed caps).
All of the above are due to the loss of electrolyte, the fluid in the caps, which effectively makes them an empty aluminum can.

Thanks very much for the info. You knowledgeable people are a great help to me. I really appreciate all the help.

Cheers,
Joey

 

[Joey777]

Hi folks I have a wee question for some help.

I damaged a few ring-pads on the PCB of the Solitaire. Instead of making jumpers or stitches I was thinking to buy the rings with the copper tab to replace the old ones, or should I say the lack of the old ones, cause there gone. The pcb is single sided I think. Is gluing ( epoxy ) new rings/tabs on a better solution to making jumpers and if so where in gods name can I buy the ring/tabs from.

Thanks ever so much.

I have repaired another channel by replacing all the caps and 1 fusecap. Then I carpet bombed the rest of the components to re-flow the joints. But The soundtracs guy from the UK, Tim, said to me not to forget that with repairs the devil is in the detail and I am not sure what exactly fixed the other ch strip. If I am to maintain this console I will have to up me game to find out whats going on.

Cheers

Edit: Oh and I got the schematic from tim which is a huge help

 

[Ike Zimbel]

You can buy proto boards that just have rings on them. A bit of heat from your iron will lift the ring off the donor board.
How you attach them to the board under repair is open to experimentation.

 

[Joey777]

You can buy proto boards that just have rings on them. A bit of heat from your iron will lift the ring off the donor board.
How you attach them to the board under repair is open to experimentation.

Thanks for your reply. Will these proto boards have a tab connected to the ring. So I can solder it to the track then epoxy it down. On the solitaire the rings that I burnt off had little tabs on them that would go onto the track.

Thanks again

 

[peterc]

What I have used before are the rivets for through hole plating, something like this:
https://za.rs-online.com/web/p/pcb-rivets-riveting-tools/1603313
Hope this helps
Peter

 

[Ike Zimbel]

What I have used before are the rivets for through hole plating, something like this:
https://za.rs-online.com/web/p/pcb-rivets-riveting-tools/1603313
Hope this helps
Peter

I think these will be way too big for this application. OP, can you post a pic or two of the pcb in question?

 

[Joey777]

Hey folks thanks very much for the reply's. Heres a pic. I measured the rings and they are roughly 2 / 2.2mm outside and about .6mm inside. I have craped away a bit of the track ready for the repair.
Cheers, joey

Edit: On this site they have a kit, but I'm looking only for the rings and I think this site is for wholesalers only

https://www.intertronics.co.uk/product/crc201-1402-land-repair-kit/

 

[Ike Zimbel]

I would just bend the cap leads over to the bare copper and solder them there. It is helpful if you have some appropriate solder flux that you can apply to the bare copper, but pre-tinning the leads and the traces with your regular solder should also work. This will not look as nice as replacing the rings, but OTOH, it will make it clear to anyone that works on the board in the future what steps were taken to deal with the lifted pads. If you do this, cut the cap leads to the desired length before you solder them. Cutting them afterwards can stress the trace that they're soldered to.