> -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Mike Morrow > Sent: Tuesday, August 10, 2004 4:35 PM > To: [email protected] > Subject: Re: [Elecraft] OT: SMT kits? > > I would *never* buy any kit that requires more than an item > or two of SMT work. SMT construction is specifically > designed *only* for machine assembly. IMO, any SMT kit must > come with almost all the SMT components pre-assembled to the > PC boards to be acceptable.
Mike This is not so my friend. Even in a production environment manual SMT assembly or rework is common place. You cannot lead a board back into a machine after placement, for a start you cannot paste it again! So any issues found by manual/AO/FFT inspection needs fixed manually. I have seen non-skilled workers, with no interest in electronics at all (and sometimes no motivation) become quite competent within a week or so on devices down to 0603 for chip parts (smallest you should really go in a kit IMHO) and even 0.65mm pitch SOIC and QFP parts. Of course to become really skilful takes a lot longer and a will/desire to do it but it shows the minor learning curve required, there are no mountains to climb if the kit is balanced between SMT parts/PTH parts. > I'm not against SMT. In fact, I wish the K1 or KX1 were > available with most of the generic components in SMT, > pre-assembled. (MFJ has almost the correct mixture in their > Cub kits.) That would be more reliable, quicker to build, > eliminate much error, reduce monotony in assembly, simplify > kit parts inventory, etc. But a kit with many SMT parts that > must be assembled by the builder grossly degrades, rather > than improves, **all** of these areas, in comparison with > conventional components. I had actually considered buying a K2 and creating a hybrid SMT/PTH version as I was looking for a bit more of a challenge than just soldering and aligning the kit. The additional space which would be freed up would allow for some more goodies to be squeezed in... (maybe ;-) ) It would also allow for builders who are not confident to complete a full kit, to buy a part assembled boards (say with R/C already fitted, thus avoiding what must be one of the most common problems for new builders, the part in the wrong place) I would guess the IC might be better left as PTH to better fit with Elecraft spares inventory Perhaps Elecraft would consider sending me the SCH in e-readable format or as netlist and set me loose on this as a mini project ... ? It would be fun, so the ground work could be done as a feasibility exercise for free. After seeing the issues caused by builders expectations of what a 'quality' build job should be I do believe SMT would help in a big way, if say 1206 sized parts were used they are not much different in size than a 1/8 W resistor and easily handled, no cropping, no worry about through hole penetration levels and perhaps a bit better performance in some areas that have trace critical routing. Just some comments of mine John (GM1BSG) > _______________________________________________ > Elecraft mailing list > Post to: [email protected] > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): > http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com > _______________________________________________ Elecraft mailing list Post to: [email protected] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
