Replacing an original XO & ceramics question

[nad]

Howdy guys, sorry to ask but I'm in need of an answer quite sharpish as I'm without music

Basically I removed a standard 16.3944 crystal and it's associated 2 x smd ceramic capacitors and replaced them with a discrete clock.

Now I wish to put the original crystal back in which is easy enough but the ceramics (15pF & 18pF) were 2mm by 1mm and far too small for me and my limited soldering skills to handle so the question......

Can I use small ceramic radials instead of the smd's? I will cut the legs back as far as possible. Will there be any implications?

Any answers would be truly appreciated.


Thanks

[tomchr]

Actually, if you have a fine tipped soldering iron and clean the component pads thoroughly with solder wick, soldering those SMDs is really not that bad.

Using 0.5 mm diameter solder, tin one pad with as little tin as you can get away with. Then heat up this tinned pad while placing the component centered on the pads. Allow to cool. Solder the other pad. Touch up the first pad. Done. If you end up with a solder blob, just wick it off with the solder wick. And use new capacitors of the appropriate case size.

If you still don't want to solder the SMDs, use as physically small leaded caps as you can find and connect them with very short leads. The caps probably go from each XTAL pin to ground, so tapping off at the crystal with one pin would work as well.

~Tom

[jcx]

you also need something to hold the cap down, the solder surface tension can cause it to stick to the iron or "tombstone" on the pad if you don't hold it down on the pads with a toothpick or dental probe

[nad]

Thanks for the replies guys, good job.

I've just put a pair of small 22pF radials (available locally) in with the legs trimmed as far back as possible and it all sounds bloody good, back to how it used to sound so I'm happy.

Thanks again!

[oshifis]

I just wonder why one would go back from external clock to on-chip clock?

[marce]

Suprisingly, using an external clock with long leads can be detrimental, clock signals should be as short as possible and away from everything else!

[nad]

Originally Posted by oshifis

I just wonder why one would go back from external clock to on-chip clock?

There were pros and cons with the 'external' clock, pros being keys and strings sounded more like, well, keys and strings, detail was released which was good within it's own right but put a CD on that isn't too well mastered and the new detail turns to a prominent scratchy hiss. The main reason for reverting back to the on board crystal was the reduction of 'kick' in the lower levels and that just wasn't for me.