[Elecraft] OT: SMT kits?

[John A. Ross [RSDTV]]

> -----Original Message-----
> From: elecraft-bounces at mailman.qth.net 
> [mailto:elecraft-bounces at mailman.qth.net] On Behalf Of Mike Morrow
> Sent: Tuesday, August 10, 2004 4:35 PM
> To: elecraft at mailman.qth.net
> 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)

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