"Michael Black" wrote in message
...

But when building with
an IC, you will have to actually build something around it in order to
get something useful.
SNIP
thirty or so years ago, when
people would write to the magazines and complain about so many ICs
being used, and about how the internal diagram of the IC was not shown.
A lot of that could be discounted as a transitional reaction, that
since ICs were new people were reacting to the newness rather than
an absolute reaction to ICs being "cheating".

Over 30 years ago I homebrewed a PDP-8 work-alike computer. It was based on
the PDP-8 instruction set. I've never seen PDP-8 electrical or detailed
logic diagrams. I used ICs, but none more complex than a 4-bit adder. The
7400-series was then too expensive for me, so I used a cheaper compatible
Signetic series in most cases. My choice to use ICs was based on a desire to
finish the project within a reasonable time - which I did. There would have
been too many parts going all-discrete. Of course discrete transistors were
used as lamp drivers, to drive the core memory select lines, and in the
voltage regulators.

At least thirty years on, it's hard to imagine that there are people
who haven't adapted.

Even using simple digital ICs, you have to know a little about the internals
of the family to avoid pitfalls - and to interface to other families. Analog
ICs require more understanding.

SNIP

On the other hand, there is validity in constantly thinking through
whether
something should be done with transistors or ICs.

Or with a $2 microcomputer. IMO, evaluating the trade-off between hardware
and software is just as important. Where should one draw the line?

My hobby RF experience has mostly been limited to VHF frequency converters.

OTOH I assembled the first FM-stereo broadcast station in the Washington DC
area, WHFS 102.3 MHz. The "components" were rather large: an HH Scott stereo
generator, an RCA "iron fireman" FM exciter, and a 1 kW power power
amplifier that had seen service a number of other places. I built a
frequency-multiplier / IPA between the exciter and the 4-400 finals, and the
power supplies including that for the finals. I built the stereo audio
console for the station; my memory is a little hazy after 40 years, but I
think the console used some audio ICs.

SNIP

But these are design decisions, not some rhetoric about how everything
must be made from scratch. Any time something is designed, it's important
not just to look at the way to do it, but at other alternatives, because
people often do get blocked by looking down only one path.

As someone else said, engineering is making what you want from the parts
that are available.

73 de bob w3otc

In , (Michael
Black) wrote:

Frank Gilliland ) writes:

Let me ask you a simple question: Suppose someone buys an SP-600, mounts some
chrome knobs, spray-paints his name on the front panel, then posts on the
newsgroup saying, "Hey, look what I built!" Would you call that "homebrew"?

I think there's a vast difference between that scenario, and building with
ICs. In your example, they are mere cosmetic work. But when building with
an IC, you will have to actually build something around it in order to
get something useful.

I am a bit surprised that you hold this opinion this late in the game.
Clearly, it was not an uncommon opinon thirty or so years ago, when
people would write to the magazines and complain about so many ICs
being used, and about how the internal diagram of the IC was not shown.
A lot of that could be discounted as a transitional reaction, that
since ICs were new people were reacting to the newness rather than
an absolute reaction to ICs being "cheating".

At least thirty years on, it's hard to imagine that there are people
who haven't adapted.

Adapted? Yes. I have built countless devices around IC's of just about every
shape and size. But I didn't design or build the -circuits- (i.e, the amps, the
oscillators, the comparators, the negative impedance converters -- the network
of active and passive components that make the device do what it does), I just
followed the instructions provided with the chip and connected the dots.

As others have pointed out, one can go down through a spiral to an
absolute level of "homebrew", but everything would be pretty bulky then.
Of course, early hams built their capacitors and all that, but it
was more necessity than some hard core belief. Once you could get
commercially available components, then they were used unless
a) someone was curious about making a capacitor or b) what was
exactly needed wasn't available.

The "level" of construction is the issue. It's one thing to homebrew the
components, but another to homebrew the circuits. I understand what you and
everyone else is saying, that "homebrew" can include the use of pre-packaged
circuits as components, that it's just a different "level" of construction. Some
might even think that building something from a kit is homebrew. I don't.
Somebody else "brewed" the circuit -- the kit-builder simply assembles the
components (connects the dots).

There are some borderline parts. It hardly makes sense to buy
a commercially made coil if you can wind one yourself, but that's
not because everyone should be making everything, but because if
someone isn't winding, they may not realize it is a simple thing,
and winding will save money.

What ICs have done is allow for a level of complexity that wasn't
available before them. Sure, there were PLLs described in the ham
magazines using tubes, but they were as complicated as a simple superhet
receiver. I can remember seeing tube based synthesizers, using multiple
crystals mixed together, and they were more complicated than a full
blown transmitter.

Superhets aren't that complicated, and neither is crystal mixing. Regardless,
crystal mixing can get expensive.

If you want to build up a whole synthesizer from transistors, it's
going to be terribly bulky. I suspect few will go to that trouble,
and instead making something simple but which won't give the performance
of a synthesizer.

Not true. Try linearizing a VCO and using a stepped voltage divider, then
beating the output against an OCXO for drift correction. It's an old method, but
it still works great. And it's a lot less complicated and expensive than using
multi-bit comparators, parallel ripple counters, a parallel-to-serial converter
(because there are very few parallel PLL chips anymore), BCD rotory switches or
a decimal-to-binary converter, phase detectors, prescalers, etc. And notice that
you still need that pesky reference oscillator!

There is so much that can be built nowadays that virtually
nobody would consider building in the tube era.

I agree. But I didn't say that every homebrew project must be built with tubes.

So I dismiss your hardcore view on this.

On the other hand, there is validty in constantly thinking through whether
something should be done with transistors or ICs. One shouldn't build
with ICs for the sake of building with them; if two transistors out of
a scrap VCR and some other components from it flash an LED perfectly
well, then what's the point of using an expensive and hard to get
IC that exists only to flash LEDs?

You're getting close....

If you don't lose anything in performance,
and only a little space, then you might as well use readily available scrap
transistors to build an IF strip, than spend money and time buying an
IC via mail order. If two transistors will supply a suitable prescaler
for Harry's project, then it likely is a good choice, because it's
easier to find transistors than prescaler ICs.

That was my point initially.

But these are design decisions, not some rhetoric about how everything
must be made from scratch. Any time something is designed, it's important
not just to look at the way to do it, but at other alternatives, because
people often do get blocked by looking down only one path.

And that, too, is a very good point. Notice that it works both ways -- I see a
lot of homebrewers getting stuck in an 'IC rut'.

For instance, as I write this it occured to me that it might be
easier for Harry to mix the VCO signal down to a frequency where
the average logic IC can work. You don't have to find a prescaler,
and the design's frequency steps won't be limited by the division of
that prescaler. There are various mixer schemes that will result
in the needed frequency. There may be reasons for not doing it this
way, but it may not even be explored because Harry hasn't given this
alternative any thought.

And the synth will be more accurate than using a prescaler, even a dual-modulus
prescaler. But I made the mistake of assuming that he knew the difference
between the two methods and had chosen the prescaler over down-conversion for
reasons unmentioned.





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In , (Michael
Black) wrote:

Frank Gilliland ) writes:

Let me ask you a simple question: Suppose someone buys an SP-600, mounts some
chrome knobs, spray-paints his name on the front panel, then posts on the
newsgroup saying, "Hey, look what I built!" Would you call that "homebrew"?

I think there's a vast difference between that scenario, and building with
ICs. In your example, they are mere cosmetic work. But when building with
an IC, you will have to actually build something around it in order to
get something useful.

I am a bit surprised that you hold this opinion this late in the game.
Clearly, it was not an uncommon opinon thirty or so years ago, when
people would write to the magazines and complain about so many ICs
being used, and about how the internal diagram of the IC was not shown.
A lot of that could be discounted as a transitional reaction, that
since ICs were new people were reacting to the newness rather than
an absolute reaction to ICs being "cheating".

At least thirty years on, it's hard to imagine that there are people
who haven't adapted.

Adapted? Yes. I have built countless devices around IC's of just about every
shape and size. But I didn't design or build the -circuits- (i.e, the amps, the
oscillators, the comparators, the negative impedance converters -- the network
of active and passive components that make the device do what it does), I just
followed the instructions provided with the chip and connected the dots.

As others have pointed out, one can go down through a spiral to an
absolute level of "homebrew", but everything would be pretty bulky then.
Of course, early hams built their capacitors and all that, but it
was more necessity than some hard core belief. Once you could get
commercially available components, then they were used unless
a) someone was curious about making a capacitor or b) what was
exactly needed wasn't available.

The "level" of construction is the issue. It's one thing to homebrew the
components, but another to homebrew the circuits. I understand what you and
everyone else is saying, that "homebrew" can include the use of pre-packaged
circuits as components, that it's just a different "level" of construction. Some
might even think that building something from a kit is homebrew. I don't.
Somebody else "brewed" the circuit -- the kit-builder simply assembles the
components (connects the dots).

There are some borderline parts. It hardly makes sense to buy
a commercially made coil if you can wind one yourself, but that's
not because everyone should be making everything, but because if
someone isn't winding, they may not realize it is a simple thing,
and winding will save money.

What ICs have done is allow for a level of complexity that wasn't
available before them. Sure, there were PLLs described in the ham
magazines using tubes, but they were as complicated as a simple superhet
receiver. I can remember seeing tube based synthesizers, using multiple
crystals mixed together, and they were more complicated than a full
blown transmitter.

Superhets aren't that complicated, and neither is crystal mixing. Regardless,
crystal mixing can get expensive.

If you want to build up a whole synthesizer from transistors, it's
going to be terribly bulky. I suspect few will go to that trouble,
and instead making something simple but which won't give the performance
of a synthesizer.

Not true. Try linearizing a VCO and using a stepped voltage divider, then
beating the output against an OCXO for drift correction. It's an old method, but
it still works great. And it's a lot less complicated and expensive than using
multi-bit comparators, parallel ripple counters, a parallel-to-serial converter
(because there are very few parallel PLL chips anymore), BCD rotory switches or
a decimal-to-binary converter, phase detectors, prescalers, etc. And notice that
you still need that pesky reference oscillator!

There is so much that can be built nowadays that virtually
nobody would consider building in the tube era.

I agree. But I didn't say that every homebrew project must be built with tubes.

So I dismiss your hardcore view on this.

On the other hand, there is validty in constantly thinking through whether
something should be done with transistors or ICs. One shouldn't build
with ICs for the sake of building with them; if two transistors out of
a scrap VCR and some other components from it flash an LED perfectly
well, then what's the point of using an expensive and hard to get
IC that exists only to flash LEDs?

You're getting close....

If you don't lose anything in performance,
and only a little space, then you might as well use readily available scrap
transistors to build an IF strip, than spend money and time buying an
IC via mail order. If two transistors will supply a suitable prescaler
for Harry's project, then it likely is a good choice, because it's
easier to find transistors than prescaler ICs.

That was my point initially.

But these are design decisions, not some rhetoric about how everything
must be made from scratch. Any time something is designed, it's important
not just to look at the way to do it, but at other alternatives, because
people often do get blocked by looking down only one path.

And that, too, is a very good point. Notice that it works both ways -- I see a
lot of homebrewers getting stuck in an 'IC rut'.

For instance, as I write this it occured to me that it might be
easier for Harry to mix the VCO signal down to a frequency where
the average logic IC can work. You don't have to find a prescaler,
and the design's frequency steps won't be limited by the division of
that prescaler. There are various mixer schemes that will result
in the needed frequency. There may be reasons for not doing it this
way, but it may not even be explored because Harry hasn't given this
alternative any thought.

And the synth will be more accurate than using a prescaler, even a dual-modulus
prescaler. But I made the mistake of assuming that he knew the difference
between the two methods and had chosen the prescaler over down-conversion for
reasons unmentioned.





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In , "Michael A. Terrell"
wrote:

snip
... Homebrewing should be used to learn something,

I couldn't agree more.

and if you want to
remain at the lowest level, enjoy yourself, but don't ridicule others
who want to learn newer methods.

Which is the 'lower' level:

a) connecting the dots

b) learning and using the circuit concepts of a high-frequency bi-stable
multivibrator to build a flip-flop suitable for use as a prescaler

....?




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In , "Michael A. Terrell"
wrote:

snip
... Homebrewing should be used to learn something,

I couldn't agree more.

and if you want to
remain at the lowest level, enjoy yourself, but don't ridicule others
who want to learn newer methods.

Which is the 'lower' level:

a) connecting the dots

b) learning and using the circuit concepts of a high-frequency bi-stable
multivibrator to build a flip-flop suitable for use as a prescaler

....?




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Frank Gilliland wrote:

....snipped....


Must be the latitude. For the sake of this discussion, I put whipped up a
flip-flop that can do 240 MHz using 2N4401's. It took me about half an hour. You
don't need to saturate those puppies, you just need a little gain.


....snipped...

OK Frank, I'm interested to see a picture and a schematic of your circuit. Do
you have web pages like Harry's?

I can't help but think that you have been more than a little rough on Harry,
someone who obviously does "homebrew" his stuff. I wish I had the time
patience and ability to construct more stuff that actually worked myself ;-).
Perhaps I'm lazy but I'll choose a suitable IC over a descrete solution 9
times out of ten. I'm not sure why you have a downer on using IC's.

I sympathise with Harry's difficulty in getting hold of parts in Sweden as it
is getting difficult to find (hobbiest) RF parts in the UK.

The hobby of radio and electronics construction is dying in the UK, so we
should be happy if some people build only kits, otherwise the kit suppliers
will go out of business too.

regards...

--Gary

Frank Gilliland wrote:

....snipped....


Must be the latitude. For the sake of this discussion, I put whipped up a
flip-flop that can do 240 MHz using 2N4401's. It took me about half an hour. You
don't need to saturate those puppies, you just need a little gain.


....snipped...

OK Frank, I'm interested to see a picture and a schematic of your circuit. Do
you have web pages like Harry's?

I can't help but think that you have been more than a little rough on Harry,
someone who obviously does "homebrew" his stuff. I wish I had the time
patience and ability to construct more stuff that actually worked myself ;-).
Perhaps I'm lazy but I'll choose a suitable IC over a descrete solution 9
times out of ten. I'm not sure why you have a downer on using IC's.

I sympathise with Harry's difficulty in getting hold of parts in Sweden as it
is getting difficult to find (hobbiest) RF parts in the UK.

The hobby of radio and electronics construction is dying in the UK, so we
should be happy if some people build only kits, otherwise the kit suppliers
will go out of business too.

regards...

--Gary

"Harry - SM0VPO" ) writes:
By the
way, the TDA7000 is also obsolete and is soon to be joining the
ZN414/5/6
and TCM3105 chips in the depths of obscurity.

BR Harry - SM0VPO

Do they have really cheap FM broadcast band only pocket radios over there,
that tune with one button (and have a second button to reset to the bottom
of
the band)?

They're everywhere here, and I've seen them for as low as $1.99 Canadian.
Curious, I bought one at that price. No cermic filter, so it's using
an oddball scheme.

Michael VE2BVW

Hi Michael,

Yes, we do have those wireless sets. The cheapest I have found is 69 crowns
(US$9) which is still quite expensive. But then again, the TDA70xx ICs are
also quite expensive, or obsolete. I am seeking a source of the chip outside
Europe for my kits.

BR Harry

"Harry - SM0VPO" ) writes:
By the
way, the TDA7000 is also obsolete and is soon to be joining the
ZN414/5/6
and TCM3105 chips in the depths of obscurity.

BR Harry - SM0VPO

Do they have really cheap FM broadcast band only pocket radios over there,
that tune with one button (and have a second button to reset to the bottom
of
the band)?

They're everywhere here, and I've seen them for as low as $1.99 Canadian.
Curious, I bought one at that price. No cermic filter, so it's using
an oddball scheme.

Michael VE2BVW

Hi Michael,

Yes, we do have those wireless sets. The cheapest I have found is 69 crowns
(US$9) which is still quite expensive. But then again, the TDA70xx ICs are
also quite expensive, or obsolete. I am seeking a source of the chip outside
Europe for my kits.

BR Harry

Frank Gilliland ) writes:

... as I write this it occured to me that it might be
easier for Harry to mix the VCO signal down to a frequency where
the average logic IC can work. You don't have to find a prescaler,
and the design's frequency steps won't be limited by the division of
that prescaler. There are various mixer schemes that will result
in the needed frequency. There may be reasons for not doing it this
way, but it may not even be explored because Harry hasn't given this
alternative any thought.

Michael VE2BVW

Hello Michael. Down-conversion has been considered, but quickly dismissed.
The sysnthesiser I need is a tool to be used for a wide variety of projects:
projects that include modulation.

Down conversion of frequency preserves any applied modulation. The prescaler
and subsequent dividers filter out modulation so that a true phase lock may
be achieved. This is especially true with WBFM where the total divide rate
must be greater than 10000 to achieve a phase lock. NBFM, with a minimum
modulating freq of, say, 250Hz, still needs a divider to divide by more than
60.

Down conversion could make a simple synth if modulation were never to be
used. I intend the project area to be both TX + RX, and to become a
"building block" for a variety of circuits.

Anyway, I have received a lot of response. My original question was "is
there a good cheap source of prescalers" (but in a long-winded way) and this
I have received. Many thanks to you and all who have given me positive
suggestions. Unfortunately I will not be melting down horses hooves to make
the glue to bond the home-beaten copper to a board to make the PCB. The only
thin board available would be ready-made plywood, and that would not be
"homebrew" ;-)

BR Harry

Frank Gilliland ) writes:

... as I write this it occured to me that it might be
easier for Harry to mix the VCO signal down to a frequency where
the average logic IC can work. You don't have to find a prescaler,
and the design's frequency steps won't be limited by the division of
that prescaler. There are various mixer schemes that will result
in the needed frequency. There may be reasons for not doing it this
way, but it may not even be explored because Harry hasn't given this
alternative any thought.

Michael VE2BVW

Hello Michael. Down-conversion has been considered, but quickly dismissed.
The sysnthesiser I need is a tool to be used for a wide variety of projects:
projects that include modulation.

Down conversion of frequency preserves any applied modulation. The prescaler
and subsequent dividers filter out modulation so that a true phase lock may
be achieved. This is especially true with WBFM where the total divide rate
must be greater than 10000 to achieve a phase lock. NBFM, with a minimum
modulating freq of, say, 250Hz, still needs a divider to divide by more than
60.

Down conversion could make a simple synth if modulation were never to be
used. I intend the project area to be both TX + RX, and to become a
"building block" for a variety of circuits.

Anyway, I have received a lot of response. My original question was "is
there a good cheap source of prescalers" (but in a long-winded way) and this
I have received. Many thanks to you and all who have given me positive
suggestions. Unfortunately I will not be melting down horses hooves to make
the glue to bond the home-beaten copper to a board to make the PCB. The only
thin board available would be ready-made plywood, and that would not be
"homebrew" ;-)

BR Harry

Frank Gilliland wrote:

The lower level is trying to force someone to do it your way.

I can think of a lower level -- saying that I'm trying to "force" anybody to do
anything simply by expressing my opinions.

You are deeply mistaken if you believe that "simply expressing my
opinions" exerts no force on other people.

Earlier, you mentioned someone who was proud of having repainted the
front panel of an old communications receiver. That person may not yet
have the knowledge or the confidence to tinker much inside the case...
but with help and encouragement, they will.

Now what kind of encouragement is it, if someone more experienced comes
along and dismisses their beginning efforts as "not homebrew"? Certainly
you will have a private opinion - but will opening your mouth make them
more likely to stay with electronics and learn something... or less?

More than 40 years ago, I actually *was* that beginner who started
"electronics" with a paintbrush. I've only just realised how lucky I was
to have escaped a put-down, right when it could have done the most
damage.


--
73 from Ian G3SEK 'In Practice' columnist for RadCom (RSGB)
Editor, 'The VHF/UHF DX Book'
http://www.ifwtech.co.uk/g3sek

Frank Gilliland wrote:

The lower level is trying to force someone to do it your way.

I can think of a lower level -- saying that I'm trying to "force" anybody to do
anything simply by expressing my opinions.

You are deeply mistaken if you believe that "simply expressing my
opinions" exerts no force on other people.

Earlier, you mentioned someone who was proud of having repainted the
front panel of an old communications receiver. That person may not yet
have the knowledge or the confidence to tinker much inside the case...
but with help and encouragement, they will.

Now what kind of encouragement is it, if someone more experienced comes
along and dismisses their beginning efforts as "not homebrew"? Certainly
you will have a private opinion - but will opening your mouth make them
more likely to stay with electronics and learn something... or less?

More than 40 years ago, I actually *was* that beginner who started
"electronics" with a paintbrush. I've only just realised how lucky I was
to have escaped a put-down, right when it could have done the most
damage.


--
73 from Ian G3SEK 'In Practice' columnist for RadCom (RSGB)
Editor, 'The VHF/UHF DX Book'
http://www.ifwtech.co.uk/g3sek

Well you've managed to hit my kill file. Good riddance
to your anti-social pap.

Bruce Raymond



"Frank Gilliland" wrote in message
...
In , "Harry - SM0VPO"
wrote:

Frank Gilliland ) writes:

... as I write this it occured to me that it might be
easier for Harry to mix the VCO signal down to a frequency where
the average logic IC can work. You don't have to find a prescaler,
and the design's frequency steps won't be limited by the division of
that prescaler. There are various mixer schemes that will result
in the needed frequency. There may be reasons for not doing it this
way, but it may not even be explored because Harry hasn't given this
alternative any thought.

Michael VE2BVW

Hello Michael. Down-conversion has been considered, but quickly
dismissed.
The sysnthesiser I need is a tool to be used for a wide variety of
projects:
projects that include modulation.

Down conversion of frequency preserves any applied modulation. The
prescaler
and subsequent dividers filter out modulation so that a true phase lock
may
be achieved.

WHAT? Even -with- modulation all you need is a low-pass filter on the
output of
the phase detector, which is what you have to do anyway. The phase lock is
"true" whether you have modulation or not, it just takes a couple extra
milliseconds to lock. If the VCO drifts faster than that then you have
some
other problems that have a higher priority than a prescaler.

BTW, if you don't have any transistors in Sweden that will work at 100
MHz, what
are you using for your VCO?

This is especially true with WBFM where the total divide rate
must be greater than 10000 to achieve a phase lock. NBFM, with a minimum
modulating freq of, say, 250Hz, still needs a divider to divide by more
than
60.

Down conversion could make a simple synth if modulation were never to be
used.

It makes a simple synth even -with- modulation.

I intend the project area to be both TX + RX, and to become a
"building block" for a variety of circuits.

Anyway, I have received a lot of response. My original question was "is
there a good cheap source of prescalers" (but in a long-winded way) and
this
I have received. Many thanks to you and all who have given me positive
suggestions. Unfortunately I will not be melting down horses hooves to
make
the glue to bond the home-beaten copper to a board to make the PCB. The
only
thin board available would be ready-made plywood, and that would not be
"homebrew" ;-)

From what you say about the availability of materials in Sweden, do you
need any
help finding some quality plywood (not obsolete, of course), and maybe an
inexpensive source? You might try posting in alt.plywood.pirate.....





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Well you've managed to hit my kill file. Good riddance
to your anti-social pap.

Bruce Raymond



"Frank Gilliland" wrote in message
...
In , "Harry - SM0VPO"
wrote:

Frank Gilliland ) writes:

... as I write this it occured to me that it might be
easier for Harry to mix the VCO signal down to a frequency where
the average logic IC can work. You don't have to find a prescaler,
and the design's frequency steps won't be limited by the division of
that prescaler. There are various mixer schemes that will result
in the needed frequency. There may be reasons for not doing it this
way, but it may not even be explored because Harry hasn't given this
alternative any thought.

Michael VE2BVW

Hello Michael. Down-conversion has been considered, but quickly
dismissed.
The sysnthesiser I need is a tool to be used for a wide variety of
projects:
projects that include modulation.

Down conversion of frequency preserves any applied modulation. The
prescaler
and subsequent dividers filter out modulation so that a true phase lock
may
be achieved.

WHAT? Even -with- modulation all you need is a low-pass filter on the
output of
the phase detector, which is what you have to do anyway. The phase lock is
"true" whether you have modulation or not, it just takes a couple extra
milliseconds to lock. If the VCO drifts faster than that then you have
some
other problems that have a higher priority than a prescaler.

BTW, if you don't have any transistors in Sweden that will work at 100
MHz, what
are you using for your VCO?

This is especially true with WBFM where the total divide rate
must be greater than 10000 to achieve a phase lock. NBFM, with a minimum
modulating freq of, say, 250Hz, still needs a divider to divide by more
than
60.

Down conversion could make a simple synth if modulation were never to be
used.

It makes a simple synth even -with- modulation.

I intend the project area to be both TX + RX, and to become a
"building block" for a variety of circuits.

Anyway, I have received a lot of response. My original question was "is
there a good cheap source of prescalers" (but in a long-winded way) and
this
I have received. Many thanks to you and all who have given me positive
suggestions. Unfortunately I will not be melting down horses hooves to
make
the glue to bond the home-beaten copper to a board to make the PCB. The
only
thin board available would be ready-made plywood, and that would not be
"homebrew" ;-)

From what you say about the availability of materials in Sweden, do you
need any
help finding some quality plywood (not obsolete, of course), and maybe an
inexpensive source? You might try posting in alt.plywood.pirate.....





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In , "Ian White, G3SEK"
wrote:

Frank Gilliland wrote:

The lower level is trying to force someone to do it your way.

I can think of a lower level -- saying that I'm trying to "force" anybody to do
anything simply by expressing my opinions.

You are deeply mistaken if you believe that "simply expressing my
opinions" exerts no force on other people.

Let me clue you in he I can't force you to read my posts. I can't prevent you
from tossing me in your killfile. And while I -can- write a post that offers a
different perspective on an issue, I -can't- make up your mind for you. And in
case you didn't notice, a newsgroup is a temporal medium -- i.e, if anyone feels
that I am forcing them to do anything it's because they have a very weak mind.

Earlier, you mentioned someone who was proud of having repainted the
front panel of an old communications receiver. That person may not yet
have the knowledge or the confidence to tinker much inside the case...
but with help and encouragement, they will.

Now what kind of encouragement is it, if someone more experienced comes
along and dismisses their beginning efforts as "not homebrew"? Certainly
you will have a private opinion - but will opening your mouth make them
more likely to stay with electronics and learn something... or less?

More than 40 years ago, I actually *was* that beginner who started
"electronics" with a paintbrush. I've only just realised how lucky I was
to have escaped a put-down, right when it could have done the most
damage.

I'm glad to hear that your fragile ego has not been disturbed by people like me
who are not afraid to tell it like it is. I may take an in-your-face approach,
but that happens to be my personality -- I don't walk on eggshells, I don't play
pop-psychology, and I don't coddle someone for doing mediocre work when I know
they can do better. If painting was all you could accomplish 40 years ago,
consider yourself proud to have learned something more about electronics since
then. But now that you have more knowledge and experience, do you still think
that homebrew electronics includes doing nothing more than painting the front
panel of a radio built by someone else? If so, then we have widely different
perspectives on the subject.

I think that Harry is selling himself and his readers short by not even
considering the use of discrete transistors (claiming that he can't find any
that are fast enough but still hasn't said what he plans to use for a VCO). I
know that he is certainly capable of making a high-speed flip-flop that will
work for his application, and probably better than any prescaler chip he can
find. Whatever he chooses, it's his choice to make. But it's also MY choice to
speak up if I think that he is ignoring a better alternative. And also to point
out that for a very public ham such as him to ask for help in a pirate newsgroup
probably isn't the best way to further the legitimate radio hobbies.

Now, how am I "forcing" anyone to do anything?





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In , "Ian White, G3SEK"
wrote:

Frank Gilliland wrote:

The lower level is trying to force someone to do it your way.

I can think of a lower level -- saying that I'm trying to "force" anybody to do
anything simply by expressing my opinions.

You are deeply mistaken if you believe that "simply expressing my
opinions" exerts no force on other people.

Let me clue you in he I can't force you to read my posts. I can't prevent you
from tossing me in your killfile. And while I -can- write a post that offers a
different perspective on an issue, I -can't- make up your mind for you. And in
case you didn't notice, a newsgroup is a temporal medium -- i.e, if anyone feels
that I am forcing them to do anything it's because they have a very weak mind.

Earlier, you mentioned someone who was proud of having repainted the
front panel of an old communications receiver. That person may not yet
have the knowledge or the confidence to tinker much inside the case...
but with help and encouragement, they will.

Now what kind of encouragement is it, if someone more experienced comes
along and dismisses their beginning efforts as "not homebrew"? Certainly
you will have a private opinion - but will opening your mouth make them
more likely to stay with electronics and learn something... or less?

More than 40 years ago, I actually *was* that beginner who started
"electronics" with a paintbrush. I've only just realised how lucky I was
to have escaped a put-down, right when it could have done the most
damage.

I'm glad to hear that your fragile ego has not been disturbed by people like me
who are not afraid to tell it like it is. I may take an in-your-face approach,
but that happens to be my personality -- I don't walk on eggshells, I don't play
pop-psychology, and I don't coddle someone for doing mediocre work when I know
they can do better. If painting was all you could accomplish 40 years ago,
consider yourself proud to have learned something more about electronics since
then. But now that you have more knowledge and experience, do you still think
that homebrew electronics includes doing nothing more than painting the front
panel of a radio built by someone else? If so, then we have widely different
perspectives on the subject.

I think that Harry is selling himself and his readers short by not even
considering the use of discrete transistors (claiming that he can't find any
that are fast enough but still hasn't said what he plans to use for a VCO). I
know that he is certainly capable of making a high-speed flip-flop that will
work for his application, and probably better than any prescaler chip he can
find. Whatever he chooses, it's his choice to make. But it's also MY choice to
speak up if I think that he is ignoring a better alternative. And also to point
out that for a very public ham such as him to ask for help in a pirate newsgroup
probably isn't the best way to further the legitimate radio hobbies.

Now, how am I "forcing" anyone to do anything?





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In , (Nick
Kennedy) wrote:

Geez, brilliant response Frank. A guy needs help finding a prescaler
and you tell him he just needs a bucket full of transistors.

That's all a chip is anyway. It's just a really small bucket.

Why not
vacuum tubes or mechanical counters?

The vacuum tube flip-flop is a neat idea, and I have that on the list for this
winter. I don't think a mechanical counter will work at 100 MHz.

But maybe -you- can help Harry out in another way: He says that he can't find
any transistors that will work above 100 MHz, yet he is building a synth to work
at least that high. So what should he use for the VCO? A vacuum tube? Or a
really, really small tuning fork?

Here's some help for your next project Frank. Just get a bunch of
wire and solder and electronic parts and stuff and hook it all
together. Like freshman lab, remember? But from your communications
style, I suspect you're still in high school.

Well, when EWU handed me my diploma I assumed they had checked my high school
records.... but hey, you never know, do ya?





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In , (Nick
Kennedy) wrote:

Geez, brilliant response Frank. A guy needs help finding a prescaler
and you tell him he just needs a bucket full of transistors.

That's all a chip is anyway. It's just a really small bucket.

Why not
vacuum tubes or mechanical counters?

The vacuum tube flip-flop is a neat idea, and I have that on the list for this
winter. I don't think a mechanical counter will work at 100 MHz.

But maybe -you- can help Harry out in another way: He says that he can't find
any transistors that will work above 100 MHz, yet he is building a synth to work
at least that high. So what should he use for the VCO? A vacuum tube? Or a
really, really small tuning fork?

Here's some help for your next project Frank. Just get a bunch of
wire and solder and electronic parts and stuff and hook it all
together. Like freshman lab, remember? But from your communications
style, I suspect you're still in high school.

Well, when EWU handed me my diploma I assumed they had checked my high school
records.... but hey, you never know, do ya?





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In om, "Bruce Raymond"
wrote:

Well you've managed to hit my kill file. Good riddance
to your anti-social pap.

Gee, I'm hurt. Maybe someday in the future, when you sift through the archives
and read this thread again, you might do so with an open technical mind. Oh, and
maybe a behavioral therapist holding your hand and to provide counseling for the
trauma of learning that not everyone behaves according to the edicts of some
middle-aged newspaper columnist.





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In om, "Bruce Raymond"
wrote:

Well you've managed to hit my kill file. Good riddance
to your anti-social pap.

Gee, I'm hurt. Maybe someday in the future, when you sift through the archives
and read this thread again, you might do so with an open technical mind. Oh, and
maybe a behavioral therapist holding your hand and to provide counseling for the
trauma of learning that not everyone behaves according to the edicts of some
middle-aged newspaper columnist.





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Frank Gilliland wrote:

In , "Harry \(SM0VPO\)"
wrote:

Hi all,
I am having a spot of bother with prescaler chips. Basically I need to find
one at the right price and availability. US$5 each is reasonable, but where
from? Is there one available that is not obsolete?

I live in Sweden and my local component shop is ELFA (Swedens answer to RS).
They don't sell ANY digital divider that operates above 50MHz, except for
the 74F163 and I cannot come up with a reliable interface circuit to couple
an oscillator into it at over 100MHz.

I found the MB501 (MC12022, SP8704) but it is obsolete and cannot find a
reliable source. I bought a couple, but that source dried up. All I need is
a divider chip that will accept a small signal up to 150MHz, is available,
cheap(ish) and will divide down to under 10MHz so that I can use CMOS to
process a synthesiser. A parallel-load synthesiser chip with in-built 150MHz
prescaler would do.

I have used "Teleport" to download over 50,000 pdf datasheets without any
luck. I have gone through most of them, but it takes a fair bit of time. If
anyone has a helpful suggestion I would appreciate it.

BR from Harry - SM0VPO

http://w1.859.telia.com/~u85920178/
harryvpo (at) hotmail (dot) com


Man, if THIS ain't a trip -- a well-known, over-rated internet homebrew tech
asking for help for a simple prescaler.

Over-rated?? Well, Harry's homebrew website is infinitely
better than yours ...

Frank Gilliland wrote:

In , "Harry \(SM0VPO\)"
wrote:

Hi all,
I am having a spot of bother with prescaler chips. Basically I need to find
one at the right price and availability. US$5 each is reasonable, but where
from? Is there one available that is not obsolete?

I live in Sweden and my local component shop is ELFA (Swedens answer to RS).
They don't sell ANY digital divider that operates above 50MHz, except for
the 74F163 and I cannot come up with a reliable interface circuit to couple
an oscillator into it at over 100MHz.

I found the MB501 (MC12022, SP8704) but it is obsolete and cannot find a
reliable source. I bought a couple, but that source dried up. All I need is
a divider chip that will accept a small signal up to 150MHz, is available,
cheap(ish) and will divide down to under 10MHz so that I can use CMOS to
process a synthesiser. A parallel-load synthesiser chip with in-built 150MHz
prescaler would do.

I have used "Teleport" to download over 50,000 pdf datasheets without any
luck. I have gone through most of them, but it takes a fair bit of time. If
anyone has a helpful suggestion I would appreciate it.

BR from Harry - SM0VPO

http://w1.859.telia.com/~u85920178/
harryvpo (at) hotmail (dot) com


Man, if THIS ain't a trip -- a well-known, over-rated internet homebrew tech
asking for help for a simple prescaler.

Over-rated?? Well, Harry's homebrew website is infinitely
better than yours ...