Also, as mentioned earlier, Wayne found one last pack of boards from the initial run, I received them today, and immediately packed them into kits. I’ll send these to the fulfillment company first thing Tuesday.
Yes, it’s only 11 kits, but that’s 11 more than are in stock right now…
Again, there will me more, I promise.
Yes, it’s only 11 kits, but that’s 11 more than are in stock right now…
Again, there will me more, I promise.
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and, in the case of an MC cart this inductance is shunted by the loading resistor which may be 100R||47k = some pF's
!!! It seems that I should get some flux, a quick recommendation would be appreciated.
My suggestion is to use the lowest melting temperature eutectic solder you can find. I've never had a problem with my roll of Alpha Metals Reliacor 11 solder. SN 63 PB 37. There may be ROHS solders out there that have similar low melting points, but I have no knowledge of them. I set my Hakko to 620 degrees F. My 2 cents.
I think it was Scott Wurcer who said that he used a hot-plate for surface mount at his company for experimenting (you can buy hot-plate at WalMart for about $20) and solder paste. You will have to play around with time and temperature to get it right. (Me. I use a toaster oven with microprocessor controlled heating element and it works great.)
Flux clean-up is a good idea.
I have used my normal soldering iron and/or a hot air handpiece for these. Both work. A hotplate will be the next thing to try, but as there's only a small handful of SMD on this board, doing them first when you've plenty of room to maneuver works well.
And, if you don't want the balanced line driver, you don't actually have to do any of the SMD. You'll need a set of K170 or K370, of course, but as of this writing, eBay seller "punkydawgs" has genuine Toshiba and sells matched octets...
And, if you don't want the balanced line driver, you don't actually have to do any of the SMD. You'll need a set of K170 or K370, of course, but as of this writing, eBay seller "punkydawgs" has genuine Toshiba and sells matched octets...
I've used solder paste and hot plate with mixed results on other projects, probably because I didn't properly control the surface temperature (used a thick griddle on the stove). Also, I use one of the several water-soluble paste flux products available with good results for either paste or conventional solder.
The paste needs to be refrigerated to extend the life of the unused portion. I didn't, and my next attempt months later failed. I went to hot air and paste after that, with good results after learning to control the temperature AND the air pressure! That entailed having an entire board of SMDs fly across the table onto the carpet.
Oh, and I also learned to cover parts I don't want to get "re-flowed" with a barrier.
For the balanced line driver on my Pearl 3 boards, I applied paste flux, then used Kester solder to tin the pads, placed the part, then dragged the solder up onto the legs of the parts.
The 2SK209s were a bit more time consuming, using this method, but my hot air solder tool was not working, so I just did the tin, place, drag method.
Oh - and the flux is paste, not liquid. The latter leaves a lot of residue, and the paste helps hold the part in place. I made a video under the microscope of me doing this with the 2SK209s and sent it to Jim - let me know if it would be helpful and I can send it to you.
The paste needs to be refrigerated to extend the life of the unused portion. I didn't, and my next attempt months later failed. I went to hot air and paste after that, with good results after learning to control the temperature AND the air pressure! That entailed having an entire board of SMDs fly across the table onto the carpet.
Oh, and I also learned to cover parts I don't want to get "re-flowed" with a barrier.
For the balanced line driver on my Pearl 3 boards, I applied paste flux, then used Kester solder to tin the pads, placed the part, then dragged the solder up onto the legs of the parts.
The 2SK209s were a bit more time consuming, using this method, but my hot air solder tool was not working, so I just did the tin, place, drag method.
Oh - and the flux is paste, not liquid. The latter leaves a lot of residue, and the paste helps hold the part in place. I made a video under the microscope of me doing this with the 2SK209s and sent it to Jim - let me know if it would be helpful and I can send it to you.
When I built my BA2018 preamp I had a misbehaving channel which I tracked down to some flux residue around a 2sk209. Cleaning that more carefully resolved the problem.
Removing residual flux has always been a chore for me until I went with 1) IPA with a toothbrush, followed by 2) Crystal Simple Green (no dye, odorant), then 3) water rinse. I haven't used the popular method of cleaning in an ultrasonic cleaner, because many times I have already installed parts that are not sealed.
