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  #61   Report Post  
Old September 22nd 06, 01:06 PM posted to rec.radio.cb
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Default Amp Design Concept -- Preliminary

On 22 Sep 2006 04:55:24 -0700, "Telstar Electronics"
wrote in
.com:

Frank Gilliland wrote:
As far as "matching problems", if you are referring to mismatched gain
in transistor pairs, that only causes harmonics. If the mismatch is
great enough to cause one transistor to run hotter than the other,
that would be due either to component failure or ****-poor quality
control.


No, I'm talking about impedance matching problems. On the input is not
a big issue... only reducing the available drive... but a mismatch on
the output is critical... and causes big problems with excessive
transistor heating... leading to premature failure.



Ok. So what does that have to do with the difference between a PCB
mounted amp and a chassis-wired amp?





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Old September 22nd 06, 01:31 PM posted to rec.radio.cb
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Default Amp Design Concept -- Preliminary

Frank Gilliland wrote:
Ok. So what does that have to do with the difference between a PCB
mounted amp and a chassis-wired amp?


I think the problem here is always one of repeatability. Anyone can
fiddle around for a time impedance matching and make one amp work...
but when you plan to make a number of units... having wires running all
around, and putting components in different physical locations
unit-to-unit makes performance unpredictable. There is another problem
that shouldn't be overlooked about the wiring method... that is the
problem of manufacturability. The PCB version is usually much easier
and faster to build... not a insignificant advantage when building
numerous units.

www.telstar-electronics.com

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Old September 22nd 06, 09:45 PM posted to rec.radio.cb
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Default Amp Design Concept -- Preliminary

On 22 Sep 2006 05:31:06 -0700, "Telstar Electronics"
wrote in
.com:

Frank Gilliland wrote:
Ok. So what does that have to do with the difference between a PCB
mounted amp and a chassis-wired amp?


I think the problem here is always one of repeatability. Anyone can
fiddle around for a time impedance matching and make one amp work...
but when you plan to make a number of units... having wires running all
around, and putting components in different physical locations
unit-to-unit makes performance unpredictable.



Well, you think wrong. I tried to explain this before but I guess it
didn't sink in the first two times, so let me make this -really-
simple:

http://bama.sbc.edu/

Many of those radios were (and still are) considered by many to be
some of the best ever built. If you really think their chassis wiring
construction made their performance "unpredictable" then there are
only three possible conclusions: One, that your experience is severely
limited; two, that your sanity is in doubt; and three, that you are
digging for the lamest of excuses to discredit me at the expense of
your own credibility.

I'm guessing the prize is behind door number three.


There is another problem
that shouldn't be overlooked about the wiring method... that is the
problem of manufacturability. The PCB version is usually much easier
and faster to build... not a insignificant advantage when building
numerous units.



Haste makes waste.





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Old September 22nd 06, 09:51 PM posted to rec.radio.cb
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Default Amp Design Concept -- Preliminary

On Fri, 22 Sep 2006 15:14:43 -0400, wrote in
:

On Fri, 22 Sep 2006 02:31:44 -0700, Frank Gilliland
wrote:

On Fri, 22 Sep 2006 04:49:01 -0400,
wrote in
:

snip
Your belief that a properly soldered connection is more likely to fail
than a connector tells us a lot about the success of your amp. This
amp symbolizes your life and is doomed from the start because of
your false beliefs. Your long stream of failures continue.



Actually the solder joint doesn't fail. The wire itself fails because
of frequent motion and repeated bending of the wire at the weakest
point -- where the wire is bare of insulation just above the solder
joint. Anybody who has ever owned a portable radio (or anything else)
with a 9V battery clip knows exactly what I'm talking about, and I'm
sure you do too.

The best connectors are the ones that clamp both the wire and the
insulation. Connectors such as IDC, SMA/B/C, BNC, Molex pin & socket,
and even common crimp-type ring/fork/spade/hook connectors are all
superior to just soldering the wire to the board.

But nice try.


It sounds like your amp can't be soldered because it's unstable.
(physically)



If that's the way it sounds to you then maybe it's time for you to
think about getting a hearing aid.


Are you sure that the reason automobile manufacturers use connectors
is because they believe a connector is more reliable than a properly
done solder joint?



No, it also has to do with servicability, which is another reason
-not- to solder the modules together.

Now.... do you have an LEGITIMATE concerns or are you just trolling?






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Old September 22nd 06, 10:09 PM posted to rec.radio.cb
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Default Amp Design Concept -- Preliminary


Are you sure that the reason automobile manufacturers use connectors
is because they believe a connector is more reliable than a properly
done solder joint?



No, it also has to do with servicability, which is another reason
-not- to solder the modules together.

Now.... do you have an LEGITIMATE concerns or are you just trolling?


You actually suggested that for reliability reasons a connector is
preferred over a proper solder joint.

A quote from you:

" Interconnection wires that are soldered have a high rate of
failure in abusive environments. That's why auto manufacturers use
connectors, even under the hood"

Give us a break. When practical a properly done solder joint is always
more reliable than a connector.
  #67   Report Post  
Old September 22nd 06, 10:58 PM posted to rec.radio.cb
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Default Amp Design Concept -- Preliminary

On a sunny day (Fri, 22 Sep 2006 17:09:50 -0400) it happened
wrote in :


Are you sure that the reason automobile manufacturers use connectors
is because they believe a connector is more reliable than a properly
done solder joint?



No, it also has to do with servicability, which is another reason
-not- to solder the modules together.

Now.... do you have an LEGITIMATE concerns or are you just trolling?


You actually suggested that for reliability reasons a connector is
preferred over a proper solder joint.

A quote from you:

" Interconnection wires that are soldered have a high rate of
failure in abusive environments. That's why auto manufacturers use
connectors, even under the hood"

Give us a break. When practical a properly done solder joint is always
more reliable than a connector.


Not exactly, solder joints can 'shear off', actually I had a failed
control valve driver in my car, where the solder that connected 2 small PCBs
just broke (likely because vibration).
Also there is the issue that now in Europe we have to use leadless solder.
Not a whole lot is known about long time durability.

On the other hand solder has been used also in mil equipment ever since WW2,
without problems, if done properly (wires supported etc).
I have had prof power supplies in, where the rubber isolation of the wires was
falling apart, creating a dangerous situation.
Mil connectors are to very high spec, and very expensive usually.
Still connectors can cause problem because of dirt etc.. But the little
things used in cars are extremely reliable.
One connector is not the other one, not even for a simple D connector,
for example AMP makes D connectors where the female has a spring around
the gold contacts, while cheaper makes use phosphor - bronze gold plated
that only touch on one point.
Good soldering is an art, I noticed what looked one dry joint in Telstars PCB.
Many connectors are these days just pressed on (ethernet, phone, etc) and just
as or more reliable then soldered connectors.
  #68   Report Post  
Old September 22nd 06, 11:43 PM posted to rec.radio.cb
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Default Amp Design Concept -- Preliminary


Many connectors are these days just pressed on (ethernet, phone, etc) and just
as or more reliable then soldered connectors.


Over thirty years?

You can slow down but you can't stop galvanic action, oxidation or
migration of foreign materials. If practical use a proper soldered
connection to eliminate most of this.
  #69   Report Post  
Old September 23rd 06, 12:11 AM posted to rec.radio.cb
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Default Amp Design Concept -- Preliminary

wrote:
Give us a break. When practical a properly done solder joint is always
more reliable than a connector.


Right on...

www.telstar-electronics.com

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Old September 23rd 06, 01:23 AM posted to rec.radio.cb
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Default Amp Design Concept -- Preliminary

On Fri, 22 Sep 2006 17:09:50 -0400, wrote in
:


Are you sure that the reason automobile manufacturers use connectors
is because they believe a connector is more reliable than a properly
done solder joint?



No, it also has to do with servicability, which is another reason
-not- to solder the modules together.

Now.... do you have an LEGITIMATE concerns or are you just trolling?


You actually suggested that for reliability reasons a connector is
preferred over a proper solder joint.

A quote from you:

" Interconnection wires that are soldered have a high rate of
failure in abusive environments. That's why auto manufacturers use
connectors, even under the hood"

Give us a break. When practical a properly done solder joint is always
more reliable than a connector.



I'll tell ya what, tnom/Brian/whoever: Both of you remember that I
have made challenges to you before. Brian refused accept my challenge
to test his claims about the harmonic specifications of his amp, and
tnom refused to accept my challenge to test his magic antenna (both
challenges are still open, BTW). So here's a REALLY SIMPLE challenge
to both of you, assuming you really are two different people (which I
seriously doubt):

Show me a connector of ANY age (a connector as I specified previously,
where the insulation is mechanically secured to the connector with the
wire) that failed due to lack of structural integrity and I'll
reconsider your argument. Because after 30+ years of experience on
hundreds upon hundreds of different pieces of electronic equipment,
from televisions to broadcast transmitters to transistor radios to
computers to military radio and telegraph equipment to you name it, I
have never seen one fail. Not one. And while you are looking, keep a
tally on how many wires you find dangling free after breaking off a
board, or hanging on to a solder joint by just a strand or two.

Until you find one, I'll consider this issue resolved.




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