February 17th 18, 08:43 PM
posted to rec.radio.amateur.homebrew
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First recorded activity by RadioBanter: Mar 2017
Posts: 209
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SMD practice
On 17/02/2018 19:54, Bob Wilson wrote:
On 2/14/2018 4:16 PM, Ralph Mowery wrote:
In article , says...
On Wed, 14 Feb 2018 16:13:29 +0000, Gareth's Downstairs Computer wrote:
Starting out late in life as an SMD convert, what are the tricks,
techniques, hints and kinks that you use for assembling them?
I use a USB microscope, got it for under UKP 20 from Lidls.
It takes some practice to actually watch the monitor rather than the
board but after a half hour or so it becomes natural.
I tried one of the inexpensive usb scopes and could not use it at all.
It was not clear enough and there was a lag time brom the time I moved
my hand to the screen updated.
They may have improved them now.
They do make some high dollar ones that are suppose to be very good, but
very pricey.
Anyway, a good microscope of some kind will go a long way in working
with the SMD.
In case you are just starting to look at microscopes:
There are really two families of optical microscopes that you will find
out there, and what really works best for something like working with
SMD is what is usually called a stereo microscope. The emphasis is on a
wide field of view, with lower magnification, compared to something a
medical researcher might use. A stereo scope will have separate optical
systems for your eyes. (Not the same as binocular eyepieces for a
non-stereo scope!) It would typically have magnification somewhere in
the range 5X - 40X, with the lower part of that best suited for this
task. And it would have a field of view that can encompass SMD parts and
also their surrounding area where you were trying to (un)mount them. A
good one is not dirt cheap, but I have seen quite respectable ones
between one and two hundred dollars. (I'll let others convert to other
currencies as they might want to!)
The "medical" kind of microscope might have magnification up to 1000X or
higher, but even at its lowest powers would have a field of view
terribly small for this kind of use.
Stereo scopes are more often used with lighting from above onto the
object, while medical scopes are often used for transmission lighting.
Bob W, WA9D
Ta. Perhaps I'll nip up the road to Brunel Microscopes in this town!
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