G.A.Evans G4SDW wrote:

Ham Radio is a technical pursuit for gentleman. Those who think
that they are Radio Hams but send their rigs back for repair are
"CBers-masquerading-as-Radio-Hams", no more, no less.

But with today's microprocessor, DSP and firmware laiden transceivers,
would repair be both possible and cost-effective once the radio amateur
has purchased a SMD rework station and expensive test gear, etc, that
would only be used for the one repair, etc?

"Leigh" wrote in message
...

But with today's microprocessor, DSP and firmware laiden transceivers,
would repair be both possible and cost-effective once the radio amateur
has purchased a SMD rework station and expensive test gear, etc, that
would only be used for the one repair, etc?

I've done surface mount repairs and /or modifications in the past without a
SMD rework station so it can be done. I find it a bit more difficult now due
to poor dexterity in my hand but, while I'd not take on a repair for someone
else (in case it goes pear shaped), I'd probably have a try on some thing of
my own- unless it was very high in value. I've picked up one of those
illuminated magnifying lenses and, with practice, you can solder SMD stuff
while looking through that. The key thing, assuming you want to replace a
component, is to get it off the PCB without damaging the pads. For a
multi-legged beast, you can snip the legs and remove them one at a time. A
bit of heat on the body of the package will help if there is any glue under
it. Ball grid arrays are more of a problem.

As regards the DSP side, if that goes bad the repair is probably more
hardware related (ie a bad component) so the firmware doesn't really come
into it. I've not checked, but some of the DSP radios may well use one of
the "off the shelf" DSP devices that you can get the development environment
for. If so, you could write your own code- assuming you Know what you are
doing.


--
73
Brian, G8OSN
www.g8osn.org.uk

Now your amateur licence is free, why not send at least £15 per year to
support the
Radio Communications Foundation or STELAR?

Brian Reay wrote:

Comments noted Brian, especially when I think back to the repairs and
modifcations I used to do with analogue satellite receivers both for SAT
TV and ATV use. Just need a steady hand and fine tip and plenty of patience.

As regards the DSP side, if that goes bad the repair is probably more
hardware related (ie a bad component) so the firmware doesn't really come
into it. I've not checked, but some of the DSP radios may well use one of
the "off the shelf" DSP devices that you can get the development environment
for. If so, you could write your own code- assuming you Know what you are
doing.

Fortunately I prefer non-DSP radios and ones where I can effect a simple
repair - especially Icom 735 and Yaesu FT747 - simple and reliable sets
and very flexible and forgiving with non-fancy aerial systems unlike
some modern sets that 'freak out' when a high SWR is presented.

Thinking of adding DSP to the 747 sometime or maybe trying a PC based
real-time solution.

Leigh...

"Leigh" wrote in message
...
Brian Reay wrote:

Comments noted Brian, especially when I think back to the repairs and
modifcations I used to do with analogue satellite receivers both for SAT
TV and ATV use. Just need a steady hand and fine tip and plenty of
patience.

As regards the DSP side, if that goes bad the repair is probably more
hardware related (ie a bad component) so the firmware doesn't really come
into it. I've not checked, but some of the DSP radios may well use one
of the "off the shelf" DSP devices that you can get the development
environment for. If so, you could write your own code- assuming you Know
what you are doing.

Fortunately I prefer non-DSP radios and ones where I can effect a simple
repair - especially Icom 735 and Yaesu FT747 - simple and reliable sets
and very flexible and forgiving with non-fancy aerial systems unlike some
modern sets that 'freak out' when a high SWR is presented.


Will, the IC756ProIII is a dream and works fine with a simple end fed for
general HF use and a reduced size loaded dipole for 5MHz.

Thinking of adding DSP to the 747 sometime or maybe trying a PC based
real-time solution.

The SDR is a good place to start with this type of thing, there is a wealth
of material around and lots of people experimenting.

Personally, I like a radio with a proper front panel, with knobs you tweak,
switches you push etc.

--
73
Brian, G8OSN
www.g8osn.org.uk

Now your amateur licence is free, why not send at least £15 per year to
support the
Radio Communications Foundation or STELAR?

There's that vacuous sneering about "Big K" again,
slipped in on the penultimate line!

You really are a stupid boy, Brian, and your ongoing public
display of playground behaviour continues to render you
unsuitable to be employed in a school IN ANY CAPACITY.

I have no doubt that your KS3 pupils whom you invoke
time and time again show a greater degree of maturity than
do you.

Grow up, OM.

"Brian Reay" wrote in message
...

As regards the DSP side, if that goes bad the repair is probably more
hardware related (ie a bad component) so the firmware doesn't really come
into it. I've not checked, but some of the DSP radios may well use one of
the "off the shelf" DSP devices that you can get the development
environment for. If so, you could write your own code- assuming you Know
what you are doing.

Expensive test gear?

Most useful is a magnifying glass to look for dry joints
I'd estimate that 90% of rigs given to me to repair
are resolved by optical examination followed by solder
re-flowing.

Soldering irons - to the bottom of one of your smaller bits,
attach a chocolate box connector (& remove the plastic
covering before it melts and fills the shack with toxic fumes!)

To the other half of the chocolate box connector, attach a
range of obscure "bits" of metal that you've fashioned to deal
with the various SMD shapes. Most Useful is an old Henley
"Solon" bit that has a slot filed in it to sit either side of an
SMD R or C.

"SMD rework station"??? Fashion from bits left over from
your Mecaano set - create an overarm with a spring loaded
plunger to bear down onto the component to prevent
tombstoning. Working end of plunger to be wooden, cocktail
stick or chopstick serves nicely. Sacrificial 'cos slowly
burns away. Only once had a problem with resins oozing
out from wood.

Come on, chaps, this is simple mechanical bodging, a trivial
matter for any self-respecting _REAL_ Radio Ham!
(Unless you fail to secure your PCB before rework,
it ain't "Rock It" Science :-) )

"Only used for the one repair"??? Is that a CBer talking? Surely
the essence of _REAL_ Ham Radio is that you're using this
type of equipment all the time? (Not true for a CBer-masquerading-
as-a-Radio-Ham, though!)

"today's microprocessor, DSP and firmware laiden transceivers"? All
_REAL_ Radio Hams thrive on how thing work and how to modify
them!

Indeed, if you're a _REAL_ Radio Ham, then your transceiver will
have been designed, constructed and modified by you, so the
" microprocessor, DSP and firmware" will be your design anyway and
therefore not a problem.

"laiden"????? ITYM "laden". I'd advise you not to seek a job in education
because of that!

"Leigh" wrote in message
...
G.A.Evans G4SDW wrote:

Ham Radio is a technical pursuit for gentleman. Those who think
that they are Radio Hams but send their rigs back for repair are
"CBers-masquerading-as-Radio-Hams", no more, no less.

But with today's microprocessor, DSP and firmware laiden transceivers,
would repair be both possible and cost-effective once the radio amateur
has purchased a SMD rework station and expensive test gear, etc, that
would only be used for the one repair, etc?