Sunday, December 14, 2014

SMD Soldering - SMD 101 - Practice Board

Back in the late 80s, early 90s, electronic components were mostly through whole. As time went by SMD (Surface Monted Devices) took over and today more and more SMD kits are available.
Prior to today I had almost zero experience soldering SMD devices. A while back I watched a video on YouTube that encouraged me to try SMD. Rightfully, the video states that you need some adequate tools for SMD "home" soldering. Here's what I used on my first try:
  1. A good quality, temperature controlled, soldering iron. I use the Hako 936 station with the Hako 907 iron. This product is now discontinued but I have been using it for a while and I really like it.
  2. The soldering iron tip is a personal choice. I mostly use the Hako T18-C3 tip, witch is a 3mm bevel tip.
  3. Soldering flux. I use MG Chemicals No Clean Flux Paste.
  4. Solder. For SMD I use Multicore 0.5mm Wire Solder, +183 → +188°C Melting Point, 40% Lead, 60% Tin.
  5. Tweezers. I got some cheap ebay ones.
  6. A magnifier.My personal choice is a head magnifier. Your millage may vary.
  7. Good lighting. Indispensable.
So, to get some experience I got some dirt cheap SMD trainnig board, They are available on ebay for peanuts. Here's a picture of all the stuff I used on this proof of concept:




Well, I must say that I am quite happy with the results. For a first try I think I got it right. If so, this opens up an entirely new world. I may even consider the M0NKA HF Radio Project. Who knows...
So, without further delay, here's the result for today's experience. It's just 4 chips, but hey, I'm excited. And I'm also including some super macro shots. :)









And some macros...






So, great fun! Now, I just have to get more practice.
73.

Tuesday, December 9, 2014

CW and Voice Keyer - FA-SM - The Funkamateur Station Manager (BX-182)

After finishing this year's (2014) CQ WW SSB contest, one of the items that I missed during the contest was a voice keyer. While searching for voice keyer kits I came across the FA-SM.
After reading about the kit and its capabilities I ended up ordering the kit online. It took a couple of days to arrive to my door. Finally, this last weekend I invested some time to put it together.
Although the building instructions are in German, a lot of information is supplied in the assembly guide, including the kit description, parts list, parts layout, and schematic.
This kit is compatible with many different radios. A very interesting matrix system is used to implement compatibility. Also supplied are sample configurations for the most popular rigs. Even if a rig is not listed (like, for example, the Kenwood TS-590S) the kit will, most likely, be compatible.
The following is a collection of pictures that document my build of this kit. After the pictures you have a brief opinion about the kit's quality and eventual problems that, as a builder, you may encounter.
Testing and using the kit will be the subject of another post (and perhaps a video).






















































So, there you have it.
The kit went together quite nicely. If I had to be very picky here are the "week" points:

1. Instead of C25 one has to install R19.
2. On the PCB bottom site one has to install R20 and C31.
3. C31 installation required that one pin had to be extended.
4. NFU1 pins do not fit the PCB and have to be adapted to fit (a delicate operation).
5. PCB was retouched (corrected) in small areas. Nothing major.

The above is, of course, minor, when compared to the following positives:

1. Very good quality PCB, although with space for improvement.
2. No parts missing and parts are very good quality.
3. Perfect fit for all parts with the exception of NFU1 (can be adapted to fit).
4. ICs sockets are provided, so no direct soldering on ICs.
5. Box quality is outstanding (face and back are a work of art).
6. All through-hole components.

My final opinion of this kit quality is very positive. Nevertheless be aware that there are quite a few parts in this kit, so it will take time and patient to put it together. Also, I recommend using good quality tools, including tweezers, a glass magnifier and a ESD soldering station like an Hakko 936 (with an adequate soldering tip).
On a future post I'll review it's working and usefulness on a ham radio station
Until then,

73.

Update 11/12/2014
The project author, Oliver Dröse, DH8BQA, has sent me some additional information about this kit. Oliver states that:

"The audio transformer (NFU1 ) indeed does not fit. This is because we changed it not long ago against a much better transformer and also made some adaptations to the whole audio output circuit to have even better audio than before. That's why you also had to solder R19 instead of C25 and the additional 2 components on the bottom side.
Of course future PCB revisions should incorporate these changes for a regular fit of those new/added components."

Also, Oliver mentioned that this is all explained in the building instructions. Of course, those are in German, and may be a challenge for English reading builders. A possible solution is, of course, to use Google Translator.