Clock Replacement

[fmak]

Because of the distance and cost of sending the Se back to W4S, I decided to do it myself.

 

Ordered the Crystek CCHD 575 50ppm XO from Mouser. Spent an hour this morning removing and refitting the XO. Powered up; it didn't work. Decided that I was too careful with soldering the unit. Got more heavy handed with the solder and it's working fine. The system is now warning up but replay at 44.1 k spdif from my Krell 20i seems clearer and brighter. Will have to wait to see the result.

 

For those who can use a soldering iron or hot air gun, the job takes an hour if one is cautious and cleans carefully

to avoid solder bridges. For those who are more practised, perhaps 1/2 hr or less. Perhaps I should have used silver solder paste for a quicker fix.

 

I used Chip Quik to try to remove the pre existing chip but quite a high temperature and prolonged heating with an

iron was needed. In the end, I set the iron to 350 C and heated the whole chip up for clean removal.

 

By mistake, I ordered too many of the CCHD 575 chip and I can spare one at cost plus postage. I also have a CCHD

950 80 MHz 25 ppm and a CCHD 100MHz 25 ppm to sell. No bargaining please as I am selling at cost plus postage of your choice.

 

I shall be happy to advise on fitting but it will be at your own risk

[Harpy]

How did you end up soldering the clock on? I have the luxury of new pcb adaptor (no surrounding circuit) and a physically bigger clock.. I was thinking of using solder paste and a heat gun. The thing I really like about Crystek are their detailed a data sheets and it has a lot of the soldering info. I never flow soldered before, but at least in my case, it seem like a simple task. Thoughts?

[fmak]

How did you end up soldering the clock on? I have the luxury of new pcb adaptor (no surrounding circuit) and a physically bigger clock.. I was thinking of using solder paste and a heat gun. The thing I really like about Crystek are their detailed a data sheets and it has a lot of the soldering info. I never flow soldered before, but at least in my case, it seem like a simple task. Thoughts?

 

I just used 190C Cardas silver bearing solder and joined the side vertical holes to the board pads. Had to be careful not to bridge the XO cover.

 

I could have used solder paste but I am not familiar with the one I had and so desisted.

 

I was worried about using a hot air gun at 260C (that's what they use in web videos) on nearby components which

I culd not have shielded effectively.

 

You can actually just put solder paste on the pads and heat up with an iron. Try it on a practice component.

[junker]

Clock upgrade! Very cool.

[Boris75]

Clock upgrade! Very cool.

 

+1. I am impressed by this upgrade. I wish I were dexterous enough to do this kind of upgrades.

[4est]

Stuff such as this goes much better if you add solder to all pads before hand and then pre flux. Then it is a simple tap with the iron to wet (flow) the pads one at a time.

How did you end up soldering the clock on? I have the luxury of new pcb adaptor (no surrounding circuit) and a physically bigger clock.. I was thinking of using solder paste and a heat gun. The thing I really like about Crystek are their detailed a data sheets and it has a lot of the soldering info. I never flow soldered before, but at least in my case, it seem like a simple task. Thoughts?

[fmak]

Stuff such as this goes much better if you add solder to all pads before hand and then pre flux. Then it is a simple tap with the iron to wet (flow) the pads one at a time.

 

Yes, the problem with XOs is that some have a slightly recessed pads and needs to sit squarely

on the pcb. With the W4S, the XO is slightly larger than the orginal and the issue is findig the

pad to touch on. This was why one has to solder from the side.