I've seen that (well a revision of it) board on this very forum, but it had different looking capacitors. Entirely. I'll try to find it.

Re: Ensoniq Soundscape leaking capacitors

It's not much help but you could try asking the poster what those caps are?

I have the card but with SMD caps.
There are only 1 or 10 micro Farad Caps. So your ready of 2.2 and 11 is 1 and 10.
Both caps on the left side of the AD chip have 1 microF ratings at 50V. Most of the red markings are also 1micr Farad.
Will look up all caps later

Eleanor1967 wrote:

Hey people, […]
Show full quote

Hey people,

I'm trying to repair a Ensoniq Soundscape S 2000 clone, the Spea Media fx. I just checked the capacitors and found 7 dead ones, should be a good place to start. The thing is that some capacitor have unexpected ratings, for example the one dead capacitor in the row of the 10 caps (I hope you know what I mean, the ones next to the Analog Devices chip) has a rating of just 1µF instead of 10µF like any other in the row. The soldering job looks factory but I just wanted to double check. The problem now is that I couldn't find any picture on the internet of my exact card, all other have a different layout in the top right corner of the card.

So question is does anybody have a card that looks like mine and could check the ratings on the marked caps ?

Best regards,
Eleanor1967

Already reviewed this? 😉

Ensoniq Soundscape leaking capacitors

Well I somehow managed to miss that thread 😉 All the ratings in question I could read from the pictures in that thread !

I just assumed because the smd caps are arranged a little different that the board layout would also be different but it seems that this is not the case. Should have looked a little closer 😀

Thanks for the heads up!

Eleanor1967 wrote:

Well I somehow managed to miss that thread 😉 All the ratings in question I could read from the pictures in that thread !

I just assumed because the smd caps are arranged a little different that the board layout would also be different but it seems that this is not the case. Should have looked a little closer 😀

Thanks for the heads up!

Main point was: I would double check the solder joints before exchanging the caps 😉

Predator99 wrote:

Main point was: I would double check the solder joints before exchanging the caps 😉

I messured the caps with the multimeter right at their legs before they go into the cap. If I don't get a reading there it should be dead no matter how good or bad the solder joint is, right ?

You would need to desolder the caps in order to correctly measure them.

Eleanor1967 wrote:

Predator99 wrote:

Main point was: I would double check the solder joints before exchanging the caps 😉

I messured the caps with the multimeter right at their legs before they go into the cap. If I don't get a reading there it should be dead no matter how good or bad the solder joint is, right ?

Not the joints at the caps..at the ICs, as written by FesterBlatz: "I'd like to note that this is my THIRD Ensoinq sound board with poor quality soldering on the fine-pitch chips. I've had two OPUS boards from eBay were the OPUS chips were literally falling off of the PCB! "

derSammler wrote:

You would need to desolder the caps in order to correctly measure them.

Generally yes, but since my caps are laid out the way they are, it doesn't matter if I measure them in circuit or not? The measurement happens between the two multimeter cables, right?

Predator99 wrote:

Not the joints at the caps..at the ICs, as written by FesterBlatz: "I'd like to note that this is my THIRD Ensoinq sound board with poor quality soldering on the fine-pitch chips. I've had two OPUS boards from eBay were the OPUS chips were literally falling off of the PCB! "

Ah, got yaa. At first glance it looks fine, but I will give it a go with the multimeter anyway. Thanks !

Eleanor1967 wrote:

Generally yes, but since my caps are laid out the way they are, it doesn't matter if I measure them in circuit or not? The measu […]
Show full quote

derSammler wrote:

You would need to desolder the caps in order to correctly measure them.

Generally yes, but since my caps are laid out the way they are, it doesn't matter if I measure them in circuit or not? The measurement happens between the two multimeter cables, right?

Predator99 wrote:

Not the joints at the caps..at the ICs, as written by FesterBlatz: "I'd like to note that this is my THIRD Ensoinq sound board with poor quality soldering on the fine-pitch chips. I've had two OPUS boards from eBay were the OPUS chips were literally falling off of the PCB! "

Ah, got yaa. At first glance it looks fine, but I will give it a go with the multimeter anyway. Thanks !

Generally, no. Just as with resistance measurement, capacitance measurement works with your meter acting as both current source (alternating instead of DC) and voltage measurement (again, AC). The capacitor would then be in parallel with everything else that remains in circuit. It is possible to measure in circuit impedance with reflectometry techniques, but not generally at a consumer price point.

Eleanor1967 wrote:

derSammler wrote:

You would need to desolder the caps in order to correctly measure them.

Generally yes, but since my caps are laid out the way they are, it doesn't matter if I measure them in circuit or not? The measurement happens between the two multimeter cables, right?

Yes the multimeter will measure between the multimeter leads.
But no, capacitors can never be measured in circuit, because the caps are connected to all kinds of stuff including ICs and other caps, so you are not measuring the cap by itself but also the whole circuit it is connected to.

@you both over me

Maybe I'm just tired, but I still don't understand why I cant measure my axial capacitors by connecting the multimeter to both sides on the front of the pcb. Doesn't the current take the shortest way possbible, which is right to the capacitor ?

Eleanor1967 wrote:

@you both over me

Maybe I'm just tired, but I still don't understand why I cant measure my axial capacitors by connecting the multimeter to both sides on the front of the pcb. Doesn't the current take the shortest way possbible, which is right to the capacitor ?

Doesn't work that way. It will measure everything in the circuit. Not only will you get a measurement from the capacitor, but from everything on either side unless nothing at all completes a circuit.

cyclone3d wrote:

Doesn't work that way. It will measure everything in the circuit. Not only will you get a measurement from the capacitor, but from everything on either side unless nothing at all completes a circuit.

Well okay, (and thanks to you all for this private tutoring 😉 )I guess this explains why I always get a +1µF on any working capacitor. Is it still safe to assume that any capcior I tested and got a reasobable reading is good ?

Not necessarily. Generally, only a capacitor failed short will be clearly indicated while still in circuit (as current flow through the rest of the circuit will be negligible, anyway). I've done up a circuit diagram of a simple pi filter with the C1 leg being measured by a capacitance meter. The second half of the diagram shows the rest of the circuit in parallel with C1 which is what will actually be measured.

Quite honestly, if this card hasn't been in current use, in some system, before you acquire it, then you really need to refresh all the electrolytics. Even unused, a capacitor only has a reasonable shelf life of roughly, ten to fifteen years, iirc.

Matthew

I just desolderd the first cap, one of which I didn't get a reading before, and it is perfectly fine out of the circuit. So much for my hope of this being any test worth a damn. I ordered some new caps, gonna recap the whole thing and go from there.

Eleanor1967 wrote:

I just desolderd the first cap, one of which I didn't get a reading before, and it is perfectly fine out of the circuit. So much for my hope of this being any test worth a damn. I ordered some new caps, gonna recap the whole thing and go from there.

Just curious, you said you are going to repair it, so in which way is it broken? Or are you just doing a full recap just in case?

You can spot check areas of the motherboard by checking two or so caps per region and replace based on that. Caps fail due to age and stress, and stress is usually due to heat. By spot checking, you're able to make some determination of where the board had bad airflow or insufficient cooling.

In this case, though, the board is old enough to probably warrant a full recap.