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  #51   Report Post  
Old September 21st 06, 11:08 PM posted to rec.radio.cb
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Default Amp Design Concept -- Preliminary

Jan Panteltje wrote:
Telstar has been at it now for years.....

At 4$ profit per amplifier you'd have to sell zillions.
:-)

Bingo.
  #52   Report Post  
Old September 22nd 06, 12:14 AM posted to rec.radio.cb
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Posts: 432
Default Amp Design Concept -- Preliminary

On Thu, 21 Sep 2006 16:02:04 -0400, wrote in
:


Reliable -- In case you haven't been paying attention, the fundamental
concept of the design is longevity. These amps are going to be around
and working long after you and your amps are dead and buried.
**This is all talk right now. The fact that you will be using
components such as connectors for board-to-board interfacing does not
lend itself to high reliability.**



I didn't suspect you were tnom but you just gave yourself away.
Regardless, have you looked inside your computer lately? Did you
notice all those 'unreliable' connectors?


Computers become outdated in about five years. You would expect
connectors to last at least that long. Mobile amps stay in use much
longer so that your comparison to computer connectors is an apple
to orange comparison.



I have a VIC-20, a C-64, a CoCo II, an original IBM PC (256K), a
generic 386DX-40, and the computer I'm typing on right now which I
slapped together about 10 years ago. All of them work fine and none of
them have connector problems, although I do have to blow the dust out
once in a while.


When was the last time you
opened up a piece of electronic equipment with a major brand name like
HP? Kenwood? GE? Motorola? Uniden? Do you really think that CONNECTORS
are an issue? Naw..... you are just looking for a reason to whine.


If you say your modular design is reliable then you must first define
reliable............HP's, Kenwoods, Motorolas that have been in use
for thirty years or more will all have connector problems.



On one of my benches I have an HP-1707B, an Eico 950B, and a Heathkit
IG-72. All are older than 30 years. I let my nephews use this bench.
Nothing on the bench has connector problems.

If there is one general type of electronic equipment that has a wide
variety of -lots- of connectors it's the reel-to-reel deck. I have a
large collection of vintage decks including Akai, Rheem/Roberts, TEAC,
Sony, Wollensak, Ampex, Concertone, Viking.....etc, etc. Most of them
are more than 30 years old and none of them have, or had, connector
problems except for the occasional loose phone jack.

When I was in the USMC the only connectors I had to replace were on
coax cables (the operators were quite rough with them) and the big,
bulky interconnection cables used on the command amtraks (which had
about 20-30 radios and intercom units and were heavily abused). None
of the connectors inside the radios ever needed replacement.

When I was working at the commercial radio shop the story was about
the same; mostly coax connectors and the occasional power plug.

During my time at the station, the only connectors that needed
replacement were ones that had frequent and punishing use, mostly 1/4"
plugs & jacks and XLR's. I don't suspect that the connectors in this
amp will get that kind of use.

So for you to categorically declare that any equipment that has "been
in use for thirty years or more will all have connector problems" is
complete and utter bull****.


If those
same connectors were solder joints you would eliminate that aspect
of reliability.



Wrong. 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 (and out of the nearly two dozen
vehicles I've owned, none of them had any connection problems,
either).


Amplifiers should be made to last even longer. Many
forty year old amplifiers are still in use today.

You should incorporate standard connectors for higher voltage lower
current lines. Use a combination connector for any combination of
higher current or lower voltage on a line. I don't have a specific
brand or link but these combination connectors can be plugged in for
ease of installation/adjustment and then soldered in place once you
are certain that you are done with your adjustment/installation.



If I take your magic antenna and stroke it real hard with an old sock,
will Barbara Eden spurt forth from the end and grant me three wishes?





  #53   Report Post  
Old September 22nd 06, 12:20 AM posted to rec.radio.cb
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Posts: 1,054
Default Amp Design Concept -- Preliminary

Frank Gilliland wrote:
If I take your magic antenna and stroke it real hard with an old sock,

will Barbara Eden spurt forth from the end and grant me three wishes?

The 70's version, or the current one? ha
  #54   Report Post  
Old September 22nd 06, 12:31 AM posted to rec.radio.cb
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Posts: 432
Default Amp Design Concept -- Preliminary

On Thu, 21 Sep 2006 14:04:58 GMT, Jan Panteltje
wrote in :

On a sunny day (Thu, 21 Sep 2006 05:38:08 -0700) it happened Frank Gilliland
wrote in
:

On Thu, 21 Sep 2006 12:25:43 GMT, Jan Panteltje
wrote in :

snip
Honestly.
Damn are we honest today.



That's friggin' twisted. I "found God" when I was in the USMC and lost
a KY-57. Not a good thing to lose. I eventually found it, but ever
since then I've been an atheist. Go figure.....


LOL, maybe it was used in-between by the Russians.
God -to me- is an experience inside yourself that causes bliss, stronger
then all the reasoning and thinking we do.



Yeah, I like Tequila too.


But in those years (sixties) in the sense of
'well there must be one after all' and 'divine justice' etc.
Or 'There but for fortune go you and I'.
It looks somehow some people are destined for some things, it always works
for them... Others do the same and fail.
And noting in nature can stop that, or change that.
Maybe that is cunning, some sort of awareness.
Some become astronauts, some lose state secrets... some always end up
with radio / tv equipment....
Maybe we have no free will, are a playing ball of all other forces in the
universe, and can see in a clear moment where we are thrown.



Nature/nurture, fate/volition, divine destiny or a dumb luck.....
throw a handful of pennies in the air and you would expect half of
them to turn up heads but they usually don't. One thing you be sure
will happen and in which you can place your faith: They will fall.


So we should not blame it on Telstar if anything is wrong with his amp.
I have to admit his PCB looks the nicest of all the ones at that site.



If an amplifier worked on 'nice looks' then I might have a different
opinion. But they don't. They work on the well-established priciples
of electronic engineering.





  #55   Report Post  
Old September 22nd 06, 01:31 AM posted to rec.radio.cb
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Posts: 985
Default Amp Design Concept -- Preliminary

True, if you expect the transistors to never be replaced. But that's
not the reality with CB amps. The owners like to swap transistors for
more power. Either that, or they overdrive the transistors and blow
them up. Replacing them tears up the board, which is why it's hard to
find an old single-board amp with good traces. Point-to-point wiring
eliminates this problem because both the transistors -and- the strips
can be replaced. The servicable life of the amp is almost indefinite
irrespective of the amount of work done to it.


Transistors in amps normally have to be replaced because the amp has
matching problems or inadequate cooling... or both. Almost all the
bootleg amps I've worked with suffered from these problems. This causes
the transistors to run red hot... and it cuts their life drastically.

As for your statement about using point to point wiring... bad idea.
This causes stray inductances and capacitances all over the place that
cause RF oscillations. Oscillations contribute to failed power
transistors, due to the tremendous power dissipation that is present
during these oscillations. Many times these oscillations can't be heard
on the air and do their damage without the operator ever knowing why
the failure occured.

http://www.telstar-electronics.com/S...202879ABTC.pdf



  #56   Report Post  
Old September 22nd 06, 02:58 AM posted to rec.radio.cb
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Posts: 123
Default Amp Design Concept -- Preliminary


If you say your modular design is reliable then you must first define
reliable............HP's, Kenwoods, Motorolas that have been in use
for thirty years or more will all have connector problems.



On one of my benches I have an HP-1707B, an Eico 950B, and a Heathkit
IG-72. All are older than 30 years. I let my nephews use this bench.
Nothing on the bench has connector problems.

If there is one general type of electronic equipment that has a wide
variety of -lots- of connectors it's the reel-to-reel deck. I have a
large collection of vintage decks including Akai, Rheem/Roberts, TEAC,
Sony, Wollensak, Ampex, Concertone, Viking.....etc, etc. Most of them
are more than 30 years old and none of them have, or had, connector
problems except for the occasional loose phone jack.

When I was in the USMC the only connectors I had to replace were on
coax cables (the operators were quite rough with them) and the big,
bulky interconnection cables used on the command amtraks (which had
about 20-30 radios and intercom units and were heavily abused). None
of the connectors inside the radios ever needed replacement.

When I was working at the commercial radio shop the story was about
the same; mostly coax connectors and the occasional power plug.

During my time at the station, the only connectors that needed
replacement were ones that had frequent and punishing use, mostly 1/4"
plugs & jacks and XLR's. I don't suspect that the connectors in this
amp will get that kind of use.

So for you to categorically declare that any equipment that has "been
in use for thirty years or more will all have connector problems" is
complete and utter bull****.


Attention. Sell your solder stock. It will fall drastically.

If those
same connectors were solder joints you would eliminate that aspect
of reliability.



Wrong. 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 (and out of the nearly two dozen
vehicles I've owned, none of them had any connection problems,
either).


I'll repeat myself. SELL YOUR SOLDER STOCK

  #57   Report Post  
Old September 22nd 06, 03:19 AM posted to rec.radio.cb
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Posts: 432
Default Amp Design Concept -- Preliminary

On 21 Sep 2006 17:31:24 -0700, "Telstar Electronics"
wrote in
.com:

True, if you expect the transistors to never be replaced. But that's
not the reality with CB amps. The owners like to swap transistors for
more power. Either that, or they overdrive the transistors and blow
them up. Replacing them tears up the board, which is why it's hard to
find an old single-board amp with good traces. Point-to-point wiring
eliminates this problem because both the transistors -and- the strips
can be replaced. The servicable life of the amp is almost indefinite
irrespective of the amount of work done to it.


Transistors in amps normally have to be replaced because the amp has
matching problems or inadequate cooling... or both. Almost all the
bootleg amps I've worked with suffered from these problems. This causes
the transistors to run red hot... and it cuts their life drastically.



Most of the bootleg amps are usually overdriven. For example, the
Pride 100 is rated for 100 watts output. But most ampheads don't know
that 100 watts means the peak power output, and when running AM they
need to reduce the input power until the output is only 25 watts
(unfortunately, the word "attenuator" isn't part of the amphead
lexicon). Then they key down for far longer than the designed duty
cycle permits ("duty cycle" also not a part of amphead vocabulary).
And -that's- why the transistors are frequently cooked. And -that's-
why this amp is going to have a variable attenuator on the front end,
a thermostatically controlled fan, and will include very detailed
instructions on how to set up the amp for different operating modes.

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.


As for your statement about using point to point wiring... bad idea.
This causes stray inductances and capacitances all over the place that
cause RF oscillations. Oscillations contribute to failed power
transistors, due to the tremendous power dissipation that is present
during these oscillations. Many times these oscillations can't be heard
on the air and do their damage without the operator ever knowing why
the failure occured.



Not only are you repeating yourself, but you are -way- out in left
field with this concern.....

Power RF bipolars are inherently stable and not likely to oscillate
(assuming no wiring errors) because (a) the input impedance is so low
that stray RF is going to be heavily damped, and (b) the power gain
isn't high enough to overcome the low impedance at the base. You have
to intentionally force these things to oscillate, and even then they
won't start without a solid kick. Ironically, the only bipolar amp I
have seen that -did- oscillate was a single-board design that someone
tried to modify for more power [insert Tim Taylor grunt here].

FET's are different because of the high input impedance at the gate.
But point-to-point wiring has been used both successfully and reliably
in commercial high-power RF transmitters ever since Molly Brown took a
ride in a lifeboat. Oscillation problems were resolved long ago when
tubes were the only choice. Damping isn't difficult, and shielding
between the input and output circuits is a common practice with both
FET's and tubes. All you need is a thin sheet of copper, aluminum, or
even a blank PC board. Got tin snips?





  #58   Report Post  
Old September 22nd 06, 09:49 AM posted to rec.radio.cb
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First recorded activity by RadioBanter: Jul 2006
Posts: 123
Default Amp Design Concept -- Preliminary

On Thu, 21 Sep 2006 16:14:29 -0700, Frank Gilliland
wrote:

On Thu, 21 Sep 2006 16:02:04 -0400, wrote in
:


Reliable -- In case you haven't been paying attention, the fundamental
concept of the design is longevity. These amps are going to be around
and working long after you and your amps are dead and buried.
**This is all talk right now. The fact that you will be using
components such as connectors for board-to-board interfacing does not
lend itself to high reliability.**


I didn't suspect you were tnom but you just gave yourself away.
Regardless, have you looked inside your computer lately? Did you
notice all those 'unreliable' connectors?


Computers become outdated in about five years. You would expect
connectors to last at least that long. Mobile amps stay in use much
longer so that your comparison to computer connectors is an apple
to orange comparison.



I have a VIC-20, a C-64, a CoCo II, an original IBM PC (256K), a
generic 386DX-40, and the computer I'm typing on right now which I
slapped together about 10 years ago. All of them work fine and none of
them have connector problems, although I do have to blow the dust out
once in a while.


When was the last time you
opened up a piece of electronic equipment with a major brand name like
HP? Kenwood? GE? Motorola? Uniden? Do you really think that CONNECTORS
are an issue? Naw..... you are just looking for a reason to whine.


If you say your modular design is reliable then you must first define
reliable............HP's, Kenwoods, Motorolas that have been in use
for thirty years or more will all have connector problems.



On one of my benches I have an HP-1707B, an Eico 950B, and a Heathkit
IG-72. All are older than 30 years. I let my nephews use this bench.
Nothing on the bench has connector problems.

If there is one general type of electronic equipment that has a wide
variety of -lots- of connectors it's the reel-to-reel deck. I have a
large collection of vintage decks including Akai, Rheem/Roberts, TEAC,
Sony, Wollensak, Ampex, Concertone, Viking.....etc, etc. Most of them
are more than 30 years old and none of them have, or had, connector
problems except for the occasional loose phone jack.

When I was in the USMC the only connectors I had to replace were on
coax cables (the operators were quite rough with them) and the big,
bulky interconnection cables used on the command amtraks (which had
about 20-30 radios and intercom units and were heavily abused). None
of the connectors inside the radios ever needed replacement.

When I was working at the commercial radio shop the story was about
the same; mostly coax connectors and the occasional power plug.

During my time at the station, the only connectors that needed
replacem
If those
same connectors were solder joints you would eliminate that aspect
of reliability.



Wrong. 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 (and out of the nearly two dozen
vehicles I've owned, none of them had any connection problems,
either).


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.
  #60   Report Post  
Old September 22nd 06, 12:55 PM posted to rec.radio.cb
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First recorded activity by RadioBanter: Jul 2006
Posts: 985
Default Amp Design Concept -- Preliminary

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.

www.telstar-electronics.com

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