Above 108MHz with FM radio (or other)?

[Dbowey]

Clarence posted:

Common use or not, the use of "you're" for "your" is *ABSOLUTELY,
TOTALLY, COMPLETELY WRONG*. It's a lovely barometer for how piss-poor
our educational system is here in the US, but it's still *WRONG*.

Don Bruder

Actually your wrong, you just can't admit it!
Pitiful attempted insult aside, you ARE acting childishly!
Stamp foot and cry loudly. No one cares!
Your language skill level is apparently a bit low, so you're screwed-up.

Why do you believe that just because you and others are incapable of using
words correctly (mis-spelling and mis-using), that general usage and defined
spelling will migrate to that low level? I believe that is wishful thinking on
your part, and is indicative of a lazy mind.

 

[Roger Johansson]

I've modified El Cheapo FM receivers by simply removing the caps
parallel to the tuning caps. Takes a bit of tweaking the trimmers and
coils but I've been able to listen in on both aviation and police
bands. Not very sensitive but it works.

Another way is to mix the antenna signal with a frequency which results
in a mix-product frequency you can receive with a normal FM receiver.

Connect a signal generator, or a home built oscillator, to the antenna,
set the oscillator to 30 MHz.

A signal of 130 MHz coming in to the antenna will be mixed with the 30
MHz from the oscillator and produce a 100 MHz signal and a 160 MHz
signal. The 100 MHz signal will be recieved by the radio as if it was a
normal FM station.

When signals of different frequencies are mixed you get two resulting
frequencies, the sum and the difference between the two frequencies.

 

[YD]

greetings all

I was wondering if there is any type of receiver I can find/purchase that would be
capable of tuning above the FM band, like from say 100 to 130 MHz. In this range I
would still want to be able to receive and demodulate FM signals (not the AM signals
of the aircraft band), but not necessarily to go so high as to be in the 2 meter ham
band. I've been looking all over the web but haven't found any receiver like this.
Does such an animal exist, or would I have to retune a standard FM band radio for
this job? Any advice/feedback/comments much appreciated.

MJ

I've modified El Cheapo FM receivers by simply removing the caps
parallel to the tuning caps. Takes a bit of tweaking the trimmers and
coils but I've been able to listen in on both aviation and police
bands. Not very sensitive but it works.

- YD.

 

[Watson A.Name - \Watt Sun, the Dark Remover\]

The english language is still strongly dominated by people who have
english as their native language, but that will soon change.

English will become the international language, and will change in
that process. It will be simplified, and special expressions will not
work in an international environment.

Greece was the dominating world power when chemistry was founded,
and we still see greek terminology in the field of chemistry.

Rome was the dominating world power when medicine was developed,
that is why latin is the language of medicine.

USA/Britain was the dominating world power in the era of electronics,
and in the era when the need for a common international language became
very strong, so english is the language of electronics and the international
language for the future.

The language english will be reformed in this process, simplified and
cleansed from strange expressions which americans use today.

English is no longer the property of americans/brits, it is now the property
of the world, and we will change it to suit our purposes.

You're clueless and don't know what you're talking about.

 

[Clarence]

Not being qualified to speak for anyone but himself,
and doing rather poorly at his attempts to avoid a tantrum,
"Dbowey" contributed nothing of value to the thread.

 

[John Fields]

The native english speaking world has had a strong influence for many
years and still does. But the number of non-english people who use
english is steadily rising, and there are 5.5 billion more people to come.

---
Your "point" being what? That as more and more people embrace English
those of us who are native English speakers will understand them less
and less?
---

I have seen how the situation has evolved over the last decade.
In the beginning I was very alone among loads of americans and a few
brits. Today the non-native english speaking participation in many
newsgroups is around 25 percent, and it is growing.

---
That's because more and more people aroung the world are discovering
newsgroups and are realizing that to participate in most, they'll need
to do as the Romans do. But, regarding your statement, so what? You
may have noticed that most of the posters with English as a second or
third language who post to this group are quite conscious of the fact
that they use the language differently from native English speaking
participants and are not at all adverse to taking instruction in the
proper use of the language.
---

I predict, based on the current tendency, that the situation will be
50/50 within 2 years, and after that the native english-speaking will be
in a quickly shrinking minority. And they will have to think about how
they speak english to be fully understood by the majority of the
participators.

---
No, we won't. Since non-native speakers will approach English from a
position of ignorance, _they_ will be obligated to learn English the
way it's used by English speaking persons, and for clarification of
poorly or misunderstood meaning will _have_ to refer to source
material, such as dictionaries, written by authorities on the matter.
Such being the case, the language will evolve, as it always has, but
its proper use, technically, will remain unquestioned. Somehow, you
seem to think that this great pool of non-native English speakers is
going to rise up, en masse, with an identical set of preconceived
notions about how the language should be used and that those of us who
use the language will be forced to bend to accept those notions as
proper in order to communicate. Get over yourself.
---

The production of movies and tv-shows was totally dominated by americans
between 1945 and now, but now we see how the rest of the world is
producing more and more programs and movies. The american dominance of
the world's media channels is quickly disappearing.

---
It's never been a question of enforced dominance, it's been a question
of the availability of local VS imported programming. What's happened
is that as the third world has become more affluent (largely through
the efforts of the native English-speaking world I might add), time
and talent has become available for the production and broadcasting of
local programming instead of the growing of food. So now, Baywatch is
still on at 8PM, but instead of dead air from 9PM until noon,
"Diverciones Bobosas" has the half hour from 9 'til 9:30...

 

[John Fields]

When signals of different frequencies are mixed you get two resulting
frequencies, the sum and the difference between the two frequencies.

 

[John Fields]

Not being qualified to speak for anyone but himself,
and doing rather poorly at his attempts to avoid a tantrum,
"Dbowey" contributed nothing of value to the thread.

 

[Don Bruder]

Until they activate the killfile...

 

[Clarence]

Not qualified to speak for anyone but himself,
"Don Bruder" contributed nothing of value to the thread.

 

[Steve Evans]

Not being qualified to speak for anyone but himself,
and doing rather poorly at his attempts to avoid a tantrum,
"Dbowey" contributed nothing of value to the thread.

"Dbowey" has never conrtibuted anything of value to _anything_ from
what i can gather.

 

[Steve Evans]

---
Don't you mean the sum _of_ and the difference between the two
frequencies?
yes.


And don't the original signals remain?

not normally, but Roger's proposing something rather _ab_normal!

 

[John Fields]

not normally, but Roger's proposing something rather _ab_normal!

---
If you heterodyne a couple of signals, f1 and f2, what you'll get out
of the mixer will be f1, f2, f1+f2, and f1-f2, so the original signals
_do_ remain; I was chiding Roger for his omission and for his little
grammatical error in the light of his recent native-English
speaker/America-bashing outbreak. Also, his proposal about mixing
with a second local oscillator was far from abnormal, it's done all
the time and it's called double conversion, as I recall.

 

[Dbowey]

Steve Evans displayed his ignorance again, with:

Not being qualified to speak for anyone but himself,
and doing rather poorly at his attempts to avoid a tantrum,
"Dbowey" contributed nothing of value to the thread.

"Dbowey" has never conrtibuted anything of value to _anything_ from
what i can gather.
I recall pointing out, a time or two, that you are an ignorant ass. That is a
big conrtibution, and I think, even a good contribution.

 

[Roger Johansson]

Yes they do, but they are of no significance in this case, the sum- or
difference-signal is what interests us after the mixing.

not normally, but Roger's proposing something rather _ab_normal!

If you look through radio amateur and DX magazines you will find ads for
small converter boxes you connect to the antenna to listen to frequencies
outside the radio's built-in bands. The box only contains a simple, but
stable, oscillator.

Theoretically, someone might say that the mixing of signals have to be
done in a non-linear component, like a diode or a transistor, and there
is no such component in the antenna.

But there usually is a non-linear component in the input stage of the
radio, and that's where the actual mixing takes place.



--
Roger J.

....what is really abnormal in the human society is what needs a lot of
training and violence to be "created", the male mind, for example.
that is what creationism is really about, the "creation" of the eternal
love and the holy matrimony, the holy ghost and the holy wrath, the
institution of the church and the mental training of young girls to
become convincing love machines..
...this leads to a dualistic society, heaven and earth, where a lot of
determinism, based on anger, is needed to have free will in social
life.. it will only cost you your soul and your sound judgement, but
what do you care about the soul, when love feels like a powerful drug.
Anger plus conviction becomes the God state of mind.
Holy cows are very convincing, and anger is what the tv is full of every night..
...sometimes the gods fail in "creating" a man, because he refuses to become
angry, then they crucify him and kill him instead..

 

[Clarence]

Childish retort noted.
Must be trying to set a record!

 

[Dbowey]

Clarence,

I'm glad you enjoyed it.

That's one more happy customer.

 

[Richard The Troll]

---
If you heterodyne a couple of signals, f1 and f2, what you'll get out
of the mixer will be f1, f2, f1+f2, and f1-f2, so the original signals
_do_ remain; I was chiding Roger for his omission and for his little
grammatical error in the light of his recent native-English
speaker/America-bashing outbreak. Also, his proposal about mixing
with a second local oscillator was far from abnormal, it's done all
the time and it's called double conversion, as I recall.

This is "basics," right? I think it's worthwhile to point out the
difference between heterodyning and just plain old ordinary "mixing". If
you just send two signals through a circuit, if the circuit is linear, you
simply get the two input frequencies in the output. There has to be some
sort of nonlinearity to cause them to modulate each other to cause there
to be sum and difference frequencies. I'd think that this kind of spoils
the idea of just setting a 30 MHz oscillator next to your antenna, and
expecting to pick up 160 MHz transmissions at 100 MHz on your FM tuner.

The beat frequencies you hear when you're calibrating your short-wave
receiver actually get produced in the detector, which the tutorials always
show as just a diode.

Plus, you have to have some selectivity at the frequency of interest, in
this case, 160 MHz, and the mixing has to be done in a circuit that's
designed to cause them to heterodyne against each other. Just an
ordinary diode would work, if the 160 MHz signal swamps out everything
else at your location. Or maybe if the 30 MHz drives the RF amp or first
mixer into saturation every half-cycle. That'd be pretty non-linear.

Thanks!
Rich

 

[Jonathan Kirwan]

"Dbowey" has never conrtibuted anything of value to _anything_ from
what i can gather.

I exclude anything from clarence, so I'm luckily never bothered with any of it
except when others follow up. Oh, well. So I missed some of the exchange until
now.

Regarding this exchange, Steve, I can tell you that when I was wrestling with
ideas for a phone indicator that relied on the phone line for power, dbowey was
very well informed on the subject and told me some things I was wrong in
assuming about it. More, he took the time and trouble to drive quite some
distance and meet me personally to help me further by giving me an original of
the appropriate specifications I needed to read. I still have those on my shelf
and I've spent time going though the parts I needed to read.

You don't get help like that, often, and he provided something that really isn't
all that easy to go find, either. He offered without my asking and I think he's
very generous when someone shows even a little effort. And that's as much as
any of us deserve to hope for, really.

Your comment is just malicious.

Jon

 

[John Fields]

This is "basics," right? I think it's worthwhile to point out the
difference between heterodyning and just plain old ordinary "mixing". If
you just send two signals through a circuit, if the circuit is linear, you
simply get the two input frequencies in the output. There has to be some
sort of nonlinearity to cause them to modulate each other to cause there
to be sum and difference frequencies.

---
You seem to have neglected to point out that in the context of _this_
thread, and in generally accepted RF terminology, 'mixing' refers to a
process which results in previously nonesistent sidebands being
generated. Were audio recording being discussed in this thread, then
'mixing' might, in that context, refer to the algebraic summation of
various signals, not to the multiplication required for modulation.
---

I'd think that this kind of spoils
the idea of just setting a 30 MHz oscillator next to your antenna, and
expecting to pick up 160 MHz transmissions at 100 MHz on your FM tuner.

---
Then you'd think wrong, since all that's necessary for the sidebands
to be generated is for the gain of the front end to be made to vary by
the new 30MHz local oscillator.

In addition, it wasn't a 160MHz carrier which was being discussed, it
was 130MHz.

From the OP:

"I was wondering if there is any type of receiver I can find/purchase
that would be
capable of tuning above the FM band, like from say 100 to 130 MHz."

And Roger's reply:

"Connect a signal generator, or a home built oscillator, to the
antenna, set the oscillator to 30 MHz.

A signal of 130 MHz coming in to the antenna will be mixed with the 30
MHz from the oscillator and produce a 100 MHz signal and a 160 MHz
signal. The 100 MHz signal will be recieved by the radio as if it was
a
normal FM station."

which was correct.
---

The beat frequencies you hear when you're calibrating your short-wave
receiver actually get produced in the detector, which the tutorials always
show as just a diode.

---
So what? All that proves is that two carriers separated in frequency
by the frequency of the beat note are being allowed to propagate all
the way the through the RF and IF chain to the detector, where they
mix, or that a signal is being injected somewhere which eventually
yields the beat note. For instance, a CW carrier generating a 455kHz
IF will generate a 1kHz beat note if a 456kHz signal is injected into
the IF.
---

Plus, you have to have some selectivity at the frequency of interest, in
this case, 160 MHz, and the mixing has to be done in a circuit that's
designed to cause them to heterodyne against each other. Just an
ordinary diode would work, if the 160 MHz signal swamps out everything
else at your location. Or maybe if the 30 MHz drives the RF amp or first
mixer into saturation every half-cycle. That'd be pretty non-linear.

---
You need no selectivity, all you need is for the new 30MHz local
oscillator to change the gain of the front end so that it looks like a
mixer and beats the 130MHz carrier down to 100MHz. From that point
on, the RF section of the radio looks like a new IF and the radio
becomes, effectively a double conversion superhet with a wide-open
front end.