olds...@tubes.com wrote:
>
> Now that I know what the initials mean, I know what these are. I have
> seen them. As far as I'm concerned, they are the devices which can't > not be repaired, unless the whole boards are replaced. Yes, I am sure > they can be repaired, but it wont be me working on them. Poor
> eyesight is just part of the reason. That's why I prefer the old tube stuff to work on, or at least the early transistorized stuff on single
> layer boards, which contain parts that can be touched without using a
> tweezers....
>
> For me, IC chips and SMDs took the fun out of electronics as a
> hobby... (Not that they are bad, but they are not for the home
> workshop, they are made for robots in factories that create them, and
> people who have very expensive test gear to trace them). I still
> recall trying to unsolder some IC chips, and ruining them every time.
> Then spending days or weeks trying to locate replacement parts,
> because they are factory numbers that can't just simply be purchased.
SMD is easier to work with than old point to point wired chassis. I
am in my mid 60s, and I have had poor eyesight all my life. I worked
with SMD boards daily at Microdyne. I now have a nice B&L Stereozoom 4
boom microscope for my projects now that I'm retired. I purchased an
adapter to be able to record video from the microscope, so that I can
post video of the techniques I use.
You need the right tools and some practice to work with the small
parts. I routinely removed and replaced 288 pin ICs without damaging the
PCB or to IC.
ASIC (Application Specific Integrated Circuits) are what you
referred to as "can't just simply be purchased". They only make sense
for products built by the millions, or for unlimited budget high end
industrial electronics.
A lot of what you think are unavailable is because you don't know
actual part numbers, VS what they have room to mare a component with.
--
Never piss off an Engineer!
They don't get mad.
They don't get even.
They go for over unity! ;-)