gb:

Nobel pursuit... in my case, I am more self-centered, I like the company
and people around...

Warmest regards,
John
--
When Viagra fails to work--you are DOOMED!!!

"Michael A. Terrell" wrote in message
...
| gb wrote:
|
| How many hours over the past year have you worked with middle or high
| schools students volunteering your time? Donating materials, time or
money
| for educational programs targeted for the audience that will make a
| difference?
|
|
| I was a volunteer advisor for the Lake county Florida Vo-Tec
| electronics program, till it was shut down. Right now I am trying to
| find the money to finish repairs to my four car garage and convert it
| into a 1200 sq ft electronics shop to teach basic electronics to the
| kids who are still interested. Its not easy when you're 100% disabled
| and living on a tiny pension, but I don't give up too easy.
|
| --
| Former professional electron wrangler.
|
| Michael A. Terrell
| Central Florida

Michael A. Terrell wrote:


I was a volunteer advisor for the Lake county Florida Vo-Tec
electronics program, till it was shut down. Right now I am trying to
find the money to finish repairs to my four car garage and convert it
into a 1200 sq ft electronics shop to teach basic electronics to the
kids who are still interested. Its not easy when you're 100% disabled
and living on a tiny pension, but I don't give up too easy.

Good luck with finding money for your garage. Sorry about Vo-tech
shutting down and your your disability and tiny pension.
Was there anything positive you wanted to say?

-Bill

On Sun, 08 May 2005 10:44:27 -0700, Tim Wescott
wrote:

The basic difference is that with a digital system you either end up
with a clean signal or a useless signal. In an analog system the
character and purity of the signal must be carefully guarded, at least
until you manage to digitize it. This means that there will be a much
greater chance that adding a new card to the radio will degrade not only
the function of the new card, but the function of all the other cards.

Second, the PC market is a huge one, with great advantages to be derived
from common equipment and software, and much smaller advantages to be
derived from commonality. This is the exact obverse of the radio
market, including homebrew radios. To make a "card" radio would be to
define a basic radio architecture, probably down to the IF frequency (or
at least to the point of forcing you to match your IF and front end).
While improvements could be made within this structure an independent
experimenter couldn't play around with such things as direct-conversion,
different IF schemes, etc., without extensive modification.

I agree that it would be quite hard to make a good quality radio with
some common backplane structure. However, connecting various
functional modules with 50 ohm input and output impedance could be
used to make quite different radios with good specifications. For
instance Mini-Circuits also makes various diode ring mixers,
amplifiers and apparently also VCOs that are boxed and have BNC or SMA
connectors. With each functional module in a metallic enclosure,
controlling the spurious radiation between modules is much easier. I
don't know that anyone would make filter modules, which would be
required to build a complete radio. Also SSB-Electronics sold separate
amplifier, mixer, frequency multiplier and crystal oscillator modules
mainly intended for a 10 GHz transverter.

Unfortunately the cost of these modules is quite high, apparently due
to low production volumes and large amount of manual labour needed to
assemble them. If there would be a large demand for such modules, it
would make sense to design them to require less manual labour to
assemble them and hence get the price to more affordable levels.

While a backplane would not be suitable for running the RF signals, it
would be a good idea to have a common control interface standard. This
might be some sort of serial interface or perhaps a CANbus interface
as used on some AMSAT satellites.

Paul OH3LWR

The fact is that hams, for sure, wouldn't pay all the extra money a well
designed plug in system would cost. Of course, I might be wrong --
anyone who thinks so (one particular person comes to mind) should get busy
designing and developing one. Perhaps there's a fortune to be made.
Certainly there's a market for a much simpler plug in system with much
less versatility than the oscilloscope system I described, as a few
manufacturers have shown. The question is, how far can this be taken
before the market dries up due to the increased cost?

Roy Lewallen, W7EL
=========================================
Would a relatively 'low cost ' plug in card system perhaps be possible by
using standard PCI (computer) or similar card connections for the 'non RF'
connections ,with standard 50 Ohms miniature connectors for all RF
connections.
It would mean that all RF card modules would have a standard RF in- and
output connector using 'miniature coax'.
It would of course mean that all the card modules involving RF would have a
universal 50 Ohms in- and output impedance.
The latter is already promoted by looking at designs in the book
'Experimental Methods in RF Design'

The above referred type of PCI card connections (or any other agreed card
standard )could then be standardised with specific 'edge connections' used
for 'ground' , +5V , -5V , +12 to15 V ,-12 to 15 V , etc

The above would facilitate home brewing and make it possible to combine home
brewed modules with specialised commercial modules. It also would enable
testing modules with standardised (impedance wise) test equipment.
Ready made or blank (single or double sided) PCBs would have identical 'card
fingers' also those supplied as part of a complete kit.

I feel that the amateur radio community would very much benefit of such a
standardised card system.

Although the amateur radio market place is relatively small , with modules
physically standardised , there would be an opportunity for a modest
'cottage industry' .

Frank GM0CSZ / KN6WH

All:

Please don't feed the troll.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

I am afraid I view "Please don't feed the troll" as "Tim Wescott thinks
everyone not agreeing with him IS a troll"...

That is NOT the proper definition of a "Troll!"

Regards,
John
--
When Viagra fails to work--you are DOOMED!!!

"Tim Wescott" wrote in message
...
| All:
|
| Please don't feed the troll.
|
| --
|
| Tim Wescott
| Wescott Design Services
| http://www.wescottdesign.com

So we might all get on the same page, here is a list of "troll definitions."

1) a newsgroup post that is deliberately incorrect, intended to provoke
readers; or a person who makes such a post

2) From the fishing term. As a noun, synonymous with flamebait. As a verb,
to post controversial or provocative messages in a deliberate attempt to
provoke flames.

3) to fish with a bait or lure trailed on a line behind a slowly moving
boat.

4) From the fishing term. As a noun, synonymous with flamebait. As a verb,
to post controversial or provocative messages in a deliberate attempt to
provoke flames.

5) This is the Scandanavian term for elf. Sometimes they are described as
being hairy and ugly, although they are able to change their shape into
anything they please. They are said to have lots of treasure, and live in
beautiful palaces.

6) SCA term for gatekeeper or door warden at a feast or other event. This
name has no historical basis. "Porter" was atypical medieval name for this
job.

7) a race of giants. They appear in various Northern mythologies. In Norse
mythology Trolls are represented as a type of goblin.

I assume you are meaning definition 1) as your definition of me being a
"troll."

Do you feel anyone opening a discussion is a troll? Is there always a
"troll" at the center of every discussion? Is the only discussion without a
"troll" one where no one has made a statement to open it--and therefore--it
is really a "silent discussion?"

Is a "troll'less discussion" one where everyone agrees with you?

Your accusing me of being a "troll" is, in my opinion, really "character
assassination" on your part--although you cloak this knife in velvet, the
gleem of its' blade is still seen...

Regards,
John
--
When Viagra fails to work--you are DOOMED!!!

"Tim Wescott" wrote in message
...
| All:
|
| Please don't feed the troll.
|
| --
|
| Tim Wescott
| Wescott Design Services
| http://www.wescottdesign.com

In article ,
John Smith wrote:

Do you feel anyone opening a discussion is a troll? Is there always a
"troll" at the center of every discussion?

No, not all discussions are trolls.

Some of the things which tend to make me consider a posting to be a
"troll" rather than a "discussion", are indications that the original
poster isn't really interested in an honest discussion. Typical signs:

- Poster shows up with a big dose of attitude on his/her shoulder.
Phrases like "You people are all laughable idiots" (fairly common
among spammers posting in the anti-spam newsgroups), or "Obviously,
anybody who has a brain will agree that xxxx is true" are red flags.

- Posters who respond to criticisms of their proposal by ignoring the
technical validity of the criticisms, or by attacking the critic
rather than the criticism (ad hominem responses), or by glossing
over the criticisms without a serious response (hand-waving).

- Posters who seem to fail to "think through" the consequences, and
costs, of their own proposals and ideas.

Is the only discussion without a
"troll" one where no one has made a statement to open it--and therefore--it
is really a "silent discussion?"

Is a "troll'less discussion" one where everyone agrees with you?

No. A troll-less discussion is where everyone involved engages in an
intellectually honest debate about the merits, disadvantages, and
costs of the suggested ideas(s). There are plenty of such troll-less
discussions, on USENET and elsewhere, where the debaters disagree
quite strongly!

Your accusing me of being a "troll" is, in my opinion, really "character
assassination" on your part--although you cloak this knife in velvet, the
gleem of its' blade is still seen...

Well, here's a third-party opinion. It's free, take it for what it's
worth to you.

From where I sit, it seems to me that your style of proposal and
debate are somewhere in the middle. They are not blatantly
"troll-ish" (in the sense of someone who is posting purely for the joy
of stirring up a fracas), but neither do they seem to be a completely
serious attempt to discuss the actual merits of your ideas (as
compared to the alternatives).

The somewhat troll-flavored signs I observe: well, there's the rather
inflammatory and biased declaration you made in the subject of "No
progress in decades." I call this trollish, because it *presumes* the
validity of the very idea that you are proposing (i.e. that a modular,
card-based radio architecture is the best one) and because it
ignores all of the progress that radio systems have made in other
areas of implementation. It seemed more inflammatory than
communicative.

I also see your response to some of the criticisms posted (including
my own) as somewhat trollish, because you seem to have responded to
serious counters by either handwaving around them, or by condemning
the poster's effort to respond to you (e.g. your comment that you
"aren't looking for people who'll tell [you] why it won't work, you're
looking for people who'll tell [you] why it will.")

One of the essentials in any scientist (and, I think, in any good
researcher or proponent) is intellectual honesty, including the
ability and willingness to figure out the weaknesses and limitations
of any theory or proposal, as well as the strengths. I think you'd
find your proposals received rather better, if you showed more clearly
that you were willing to think them out to this degree in advance of
posting them, and were open to receiving honest criticism.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

Dave:


Surprisingly, we agree on most of ALL of this!!!



However, do not consider myself a troll if my methods are simply different
than others are accustomed to either; neither do I think I am a troll if I
do not wish to the “standard operating procedure” which some newsgroup of
“good ole buddies” has adopted—secret handshakes, phrases, etc. I have
outgrown…



Although common decency and respect for the right of another to hold an
opinion, belief or view contrary to ones own is necessary—I don’t see these
exchanges—when composed of overly narrow methods of exchange and interaction
as being beneficial to any…



Warmest regards,

John

--
When Viagra fails to work--you are DOOMED!!!

"Dave Platt" wrote in message
...
| In article ,
| John Smith wrote:
|
| Do you feel anyone opening a discussion is a troll? Is there always a
| "troll" at the center of every discussion?
|
| No, not all discussions are trolls.
|
| Some of the things which tend to make me consider a posting to be a
| "troll" rather than a "discussion", are indications that the original
| poster isn't really interested in an honest discussion. Typical signs:
|
| - Poster shows up with a big dose of attitude on his/her shoulder.
| Phrases like "You people are all laughable idiots" (fairly common
| among spammers posting in the anti-spam newsgroups), or "Obviously,
| anybody who has a brain will agree that xxxx is true" are red flags.
|
| - Posters who respond to criticisms of their proposal by ignoring the
| technical validity of the criticisms, or by attacking the critic
| rather than the criticism (ad hominem responses), or by glossing
| over the criticisms without a serious response (hand-waving).
|
| - Posters who seem to fail to "think through" the consequences, and
| costs, of their own proposals and ideas.
|
| Is the only discussion without a
| "troll" one where no one has made a statement to open it--and
therefore--it
| is really a "silent discussion?"
|
| Is a "troll'less discussion" one where everyone agrees with you?
|
| No. A troll-less discussion is where everyone involved engages in an
| intellectually honest debate about the merits, disadvantages, and
| costs of the suggested ideas(s). There are plenty of such troll-less
| discussions, on USENET and elsewhere, where the debaters disagree
| quite strongly!
|
| Your accusing me of being a "troll" is, in my opinion, really "character
| assassination" on your part--although you cloak this knife in velvet, the
| gleem of its' blade is still seen...
|
| Well, here's a third-party opinion. It's free, take it for what it's
| worth to you.
|
| From where I sit, it seems to me that your style of proposal and
| debate are somewhere in the middle. They are not blatantly
| "troll-ish" (in the sense of someone who is posting purely for the joy
| of stirring up a fracas), but neither do they seem to be a completely
| serious attempt to discuss the actual merits of your ideas (as
| compared to the alternatives).
|
| The somewhat troll-flavored signs I observe: well, there's the rather
| inflammatory and biased declaration you made in the subject of "No
| progress in decades." I call this trollish, because it *presumes* the
| validity of the very idea that you are proposing (i.e. that a modular,
| card-based radio architecture is the best one) and because it
| ignores all of the progress that radio systems have made in other
| areas of implementation. It seemed more inflammatory than
| communicative.
|
| I also see your response to some of the criticisms posted (including
| my own) as somewhat trollish, because you seem to have responded to
| serious counters by either handwaving around them, or by condemning
| the poster's effort to respond to you (e.g. your comment that you
| "aren't looking for people who'll tell [you] why it won't work, you're
| looking for people who'll tell [you] why it will.")
|
| One of the essentials in any scientist (and, I think, in any good
| researcher or proponent) is intellectual honesty, including the
| ability and willingness to figure out the weaknesses and limitations
| of any theory or proposal, as well as the strengths. I think you'd
| find your proposals received rather better, if you showed more clearly
| that you were willing to think them out to this degree in advance of
| posting them, and were open to receiving honest criticism.
|
| --
| Dave Platt AE6EO
| Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
| I do _not_ wish to receive unsolicited commercial email, and I will
| boycott any company which has the gall to send me such ads!

From: Paul Keinanen on Sun,May 8 2005 11:54 pm

On Sun, 08 May 2005 10:44:27 -0700, Tim Wescott
wrote:

The basic difference is that with a digital system you either end up
with a clean signal or a useless signal. In an analog system the
character and purity of the signal must be carefully guarded, at
least
until you manage to digitize it. This means that there will be a
much
greater chance that adding a new card to the radio will degrade not
only
the function of the new card, but the function of all the other
cards.

Second, the PC market is a huge one, with great advantages to be
derived
from common equipment and software, and much smaller advantages to be

derived from commonality. This is the exact obverse of the radio
market, including homebrew radios. To make a "card" radio would be
to
define a basic radio architecture, probably down to the IF frequency
(or
at least to the point of forcing you to match your IF and front end).

While improvements could be made within this structure an independent

experimenter couldn't play around with such things as
direct-conversion,
different IF schemes, etc., without extensive modification.

I agree that it would be quite hard to make a good quality radio with
some common backplane structure. However, connecting various
functional modules with 50 ohm input and output impedance could be
used to make quite different radios with good specifications.

That's already been done in the RF industry for a half
century.

As one example, take the U.S.' AN/PRC-8, -9, -10 series
of manpack transceivers covering high-HF into low-VHF.
Still in the vacuum tube era, all of the IF modules
included the IF tuned circuits as well as the subminiature
tube. If the tube filament burned out, the entire module
was replaced. NO alignment tweaking was required. Design
was done back around 1950.

As for standards on control...start with the ATLAS (for
USAF test equipment) and continue on to the IEEE-488
interface. Those standards worked with "modular"
components capable of testing receiver sensitivity down
to noise level with KNOWN signal levels. By the way,
test equipment for RF has been standardized at 50 Ohms
since WW2 days.

For
instance Mini-Circuits also makes various diode ring mixers,
amplifiers and apparently also VCOs that are boxed and have BNC or SMA
connectors. With each functional module in a metallic enclosure,
controlling the spurious radiation between modules is much easier. I
don't know that anyone would make filter modules, which would be
required to build a complete radio. Also SSB-Electronics sold separate
amplifier, mixer, frequency multiplier and crystal oscillator modules
mainly intended for a 10 GHz transverter.

Unfortunately the cost of these modules is quite high, apparently due
to low production volumes and large amount of manual labour needed to
assemble them. If there would be a large demand for such modules, it
would make sense to design them to require less manual labour to
assemble them and hence get the price to more affordable levels.

Define "more affordable." :-)

"Filter modules" have and are built to order by dozens
(if not hundreds worldwide) of companies. The costs
ARE high because they are built TO specifications and
such have to be TESTED to meet those specifications.
Is there comparable KNOWN/calibrated test equipment
in the average homebrewer's hobby workshop that is
comparable...even at "low" frequencies of HF? Actually,
Kaylie's Mini-circuits DOES use calibrated, automatic
test equipment to check out each module, small
quantities to large quantities. Mini-Circuits doesn't
have the market demand to do production runs in the
10,000-lot quantities.

The mystique on L-C filters is largely that...mystique.
Without some good, calibrated test equipment, it is
very difficult to determine what a "filter module"
has for performance. Synthesis (design) of the values
for a particular filter type was arduous until folks
came out with computer-aided design. I have a working
freeware program for PCs on that...send a message in
private e-mail if you want one transmitted to you.

As to cost, just look at a cellular telephone handset.
Those can cost around US$ 50 each, new. They work in
a band roughly centered at 1.0 GHz. Microwaves.
Complete microwave Rx-Tx with synthesized tuning.
For half a hundred US dollars here. A mere 30 years
ago that would be almost inconceivable. Three years
ago the U.S. Census Bureau said that one in three
Americans have a cell phone subscription. That's
roughly 100 MILLION units either out there or waiting
to be used. Market quantity and competition in that
market are the key to bringing down costs. Radio
hobbyists just cannot possibly get close to such
market quantities.

While a backplane would not be suitable for running the RF signals, it
would be a good idea to have a common control interface standard. This
might be some sort of serial interface or perhaps a CANbus interface
as used on some AMSAT satellites.

Who says a "backplane would not be suitable?" :-)
Those PC backplanes carry terribly broad spectra of
RF...from (literally) DC on up to the low microwaves.
No "perhaps" about it. Thing is, the layout can NOT
be done as if it were wire-wrap; i.e., in random
order of wire placement. With broadbanding anything,
every single adjacent trace becomes a COUPLER and
unwitting layouts can produce remarkable crosstalk
effects. Designers have known that for decades and
handle it...all kinds of Application Notes and info
out in public access available for anyone...just too
specialized for the "weekender" small-project
assembler hobbyist.

The IEEE-488 is a mature standard for control and
interface for computer-controlled, interconnected
systems. Would be a bit TOO all-inclusive for a
special-purpose new design. The "interface" does
NOT have to be some kind of "new" thing used on the
latest whatever out in space. It's just a control-
and-response avenue carrying signals of a standardized
kind...a few wires/traces perhaps...laid out properly
if required to be broadbanded or broad in dynamic
signal range. Not a big thing, but needs some
THOUGHT before becoming hardware.