Broken Cap on Pulsar 2 PCI - Advice.

[radar23]

Hello Fellow Scopers... I just recieved a pulsar2 PCI in the post. Unfortunatey, the sender did not protect the PCI board for the trip, and It arrived looking like this.






Can anyone tell me what the part type is that has broken off? (ie cap, resistor etc.)

Then can someone tell me what this part is for?

And then can someone re-assure me that soldering the part back on should hopefully fix the board.

I am pretty good with the soldering iron so I have no fear over doing that. I am just worried about the heat damage to the surrounding components.

Why don't people post things in boxes...

Thanks in advance.

Radar23

[garyb]

yes, that's a capacitor.

i've seen those break off before. if you can resolder it, do so, but beware that you get the polarity correct(indicated by the black mark).

Ralf in service can confirm(it'd be a good idea to ask him), but the card should still work. that one cap isn't vital....

afaik, the cap is on the negative(ground) side of the circuit and it's purpose is to tame voltage spikes.

[valis]

Or buffer current flow for when there's a sudden increase in load. Caps are used also in the analog output section to improve transient response/slew rate.

[radar23]

Thanks for the quick responses.... I shall endevor to re solder is little cap with great care over the weekend I think.

If all works well I will be the proud ower of a 3x pular2 18 dsp rig! Sweet.

wish me luck.

[garyb]

good luck.

as i said, on the other card i saw with one of those caps broken, Ralf indicated that it would work fine without the cap and it did...

valis, your explanation of the cap's use sound more likely...

[capacitor]

Another thing to consider: soldering a couple of fine, short shielded wires to the breaks, and soldering the cap (or a replacement) to the wires. Wires to the cap, tack the cap in place, then solder the wires to the board and done. The less heat applied to the circuit board, the better imo.

Check those other capacitors/components with a fine tooth comb (i.e. magnifying glass, strong reading glasses etc). You may find another that was compromised. However - I have a series II Project too - they are made well and should be robust.

I wish you the best in getting her back in action!

[astroman]

I don't see any problems at all to put this back in place - apply a little bit of heat at on side just to 'glue' it to position, then solder the pads on the other side. Wait a moment and then properly solder the 'glue' side.
It's a rather typical 'break' as the soldering 'focus' in production is on the sensitive chips, so the bigger parts sometimes don't get enough heat.
As Gary mentioned: attention to polarity

cheers, Tom

[capacitor]

+1 after looking at these pics. Also, wires would make it obvious that a fix had been performed. Do it like Astroman suggested and it is like it never happened

[radar23]

All Done....!

I soldered on the Cap this evening, very simple job in the end. I just tinned the legs of the Cap, de-soldered to contacts and re-tinned them. Then with a careful hand and some delicate heat, I plopped the little cap back on.

I will post the repair pictures tomorrow.

I have installed the Pulasr2 Card in my PC, along with the other card I bougth, and after some basic testing I am certain all is well. I even did the old Master Verb Pro test, and got 16 versions running before the DSP ran out, no PCI overload. sweet.

Thanks to everyone for the suggestions and support.

Radar

[garyb]

[Polarity]

Also I received my 2nd hand Pulsar Card with a condenser broken when arrived.
It worked without problems and still it's working after years...