3.58U
I don't remember seeing a "Y" designation before. What is it?
Thanks,
--
Dave C.
dave-us...@mailblocks.com
Tom Woodrow
www.dacworks.com
"Tom Woodrow" <tomwo...@comcast.net> wrote in message
news:xpi%a.153222$Ho3.18533@sccrnsc03...
This makes me wonder: Where did some of these letter designations come
from? Why are most IC's labeled U1, U2, etc..? I'm guessing Y is from
crYstal? How about L (or sometimes E) for inductors? Q for transistors?
--
If there is a no_junk in my address, please REMOVE it before replying!
All junk mail senders will be prosecuted to the fullest extent of the
law!!
http://home.att.net/~andyross
> it is a crystal or ceramic resenator, possibly 3.58mHz
Thanks.
Is 3.58 MHz common? It looks familiar, like a common TV oscillator frequency,
IIRC. Should be able to easily find a replacement?
--
Dave C.
dave-us...@mailblocks.com
> On Fri, 15 Aug 2003 21:28:13 -0700, Tom Woodrow wrote
> (in message <xpi%a.153222$Ho3.18533@sccrnsc03>):
>
>
>>it is a crystal or ceramic resenator, possibly 3.58mHz
>
>
> Thanks.
>
> Is 3.58 MHz common? It looks familiar, like a common TV oscillator frequency,
> IIRC. Should be able to easily find a replacement?
It's the color burst reference (at least for NTSC, I don't know about PAL).
Every TV has one.
--
+--------------------------------+----------------------------------+
| George H. Patrick, III | Resources for PCB Designers on |
| geo...@pcb-designer.com | the Web - The Designer's Den |
| George.H...@tektronix.com | http://www.pcb-designer.com |
+--------------------------------+----------------------------------+
| Take what you like and leave the rest... My opinion ONLY. |
+-------------------------------------------------------------------+
I don't thing the Y prefix is for a crystal. Like was stated I thought
it was for a resonnant filter, i.e ceramic or other type. These tend to
have 3 legs instead of a crystal's 2.
These resonnators are often used to replace a tuned coil because they
are a lot smaller, have a high Q, and can be more accurate without
requiring any tuning adjustment.
AR> From: Andrew Rossmann <andysnewsreply@no_junk.comcast.net>
AR> In article <xpi%a.153222$Ho3.18533@sccrnsc03>, tomwo...@comcast.net
AR> says...
> it is a crystal or ceramic resenator, possibly 3.58mHz
AR> This makes me wonder: Where did some of these letter designations
AR> come from? Why are most IC's labeled U1, U2, etc..? I'm guessing Y is
AR> from crYstal? How about L (or sometimes E) for inductors? Q for
AR> transistors?
AR> --
AR> If there is a no_junk in my address, please REMOVE it before replying!
AR> All junk mail senders will be prosecuted to the fullest extent of the
AR> law!!
AR> http://home.att.net/~andyross
... Dunno if we'll get that past the CSA und UL 'owever.
> "Andrew Rossmann" bravely wrote to "All" (16 Aug 03 07:52:40)
> --- on the topic of "Re: "Y1" component designation?"
>
> I don't thing the Y prefix is for a crystal. Like was stated I thought
> it was for a resonnant filter, i.e ceramic or other type. These tend to
> have 3 legs instead of a crystal's 2.
>
> These resonnators are often used to replace a tuned coil because they
> are a lot smaller, have a high Q, and can be more accurate without
> requiring any tuning adjustment.
Now I (OP) am confused. It's not a crystal. I thought a ceramic resonator has
only 2 leads, while a filter has more(?)
But you say (I think you did...) that it is a filter.
Can you clarify a little?
--
Dave C.
dave-us...@mailblocks.com
> The color burst frequencies are 3.579545 MHz (NTSC) and 4.433619 MHz (PAL).
> Since yours is rounded to 3.58 it is most likely a ceramic resonator rather
> than a crystal.
If I have a difficult time finding a replacement ceramic resonator, can I
replace it in this circuit with a crystal? Are they directly compatible?
<http://www.jameco.com/cgi-
bin/ncommerce3/ExecMacro/jameco/searchResult.d2w/report?sort=BPA&search=137816
cd>
Can I replace a ceramic resonator with this xtal? Do I need to add anything
else to the circuit?
I'm pretty sure I've seen Y1 to denote crystals, but for the life of
me I can't be certain. Of course! If nowhere else, the ARRL used Y1
to denote a crystal. Bill Orr's Radio Handbook used the same prefix.
Now, I'm not sure the circuit board designator would differentiate
between a crystal and a ceramic resonator. But since I just scrapped
a bunch of boards last week, I don't have anything handy to check.
So I think a manufacturer might use X or Y for the crystal, but
whatever they used, they'd use it for ceramic resonators.
Now for the issue of "filter". A lot of these oscillators use a pair
of capacitors from each side of the crystal (or ceramic resonator)
to ground:
------|Y1|---------
| |
C1 C2
|________|
ground
Not all oscillators, just the type you often see in digital equipment.
You'd need them whether Y1 was a crystal or a ceramic resonator.
Now, since that's the case, and ceramic resonators can include them,
you can get ceramic resonators with those two capacitors built in.
I would not call it a filter, but it would have three leads (the middle
one being ground). If you put one of those in where the capacitors
were already in place, you might not get good oscillation.
There are of course little ceramic things with three leads that are
indeed filters, as in IF filters. You can use those in oscillators,
I've seen circuits that sort of amount to novelty, but they are not
the same thing as the ceramic filters with the built in capacitors.
Now, if I remember your original post, it sure sounds like a ceramic
resonator. I'd say they are interchangeable with crystals (or vice
versa), given the issue of those external capacitors. If the
circuit expects a resonator with the capacitors, the crystal will
require external capacitors (because they will not be built in).
Ceramic resonators are cheaper to manufacture than crystals, and
not as good in performance as crystals. But for many applications,
the ceramic resonator is fine. Putting a crystal should be fine,
though the reverse situation might not be suitable (depending on
the specific application). There might be a few places where
the design requires the ceramic resonator, because I gather they
can be varied in frequency by changing load capacitors, more than
the average crystal. But that would be a specific exception.
If the thing has two leads only, then the issue of the extra
capacitors doesn't exist. Pull a crystal of the correct frequency
out of something, and there you go.
Michael
> Now, if I remember your original post, it sure sounds like a ceramic
> resonator. I'd say they are interchangeable with crystals (or vice
> versa), given the issue of those external capacitors.
There are no caps in this oscillator circuit. The resonator has a 33 ohm (or
22; I can't tell if those are red or orange stripes) resistor connecting each
of its 2 pins to ground. One end of the resonator also connects directly to a
pin of the microcontroller. The other end connects via a 1M ohm resistor to
another pin of the microcontroller.
Given this circuit, can I replace the resonator with a crystal? Such as:
<http://www.jameco.com/cgi-
bin/ncommerce3/ExecMacro/jameco/searchResult.d2w/report?sort=BPA&search=137816
cd>
That really really really sounds like 33 pF caps to me. Are those "resistors"
the same color as the other resistors on the PCB?
--
All relevant people are pertinent.
All rude people are impertinent.
Therefore, no rude people are relevant.
-- Solomon W. Golomb
>In article <xpi%a.153222$Ho3.18533@sccrnsc03>, tomwo...@comcast.net
>says...
>> it is a crystal or ceramic resenator, possibly 3.58mHz
>
> This makes me wonder: Where did some of these letter designations come
>from? Why are most IC's labeled U1, U2, etc..? I'm guessing Y is from
>crYstal? How about L (or sometimes E) for inductors? Q for transistors?
There was, probably still is, a MIL spec that defines standard
reference designators. It's mostly familiar, with some quaint usages,
such as D for dynamotor, DS for lamp, and CR (crystal rectifier) for
diode. I think there's an ANSI standard, too. Nowadays, everybody
seems to make up their own weird designators, like CON for connector,
TR for transistor, and IC for, well, an IC.
Anybody got horrible examples?
John
I just scrapped an IBM aptiva board and wouldn't you know it the
crystals are labelled with the "Y" prefix!
BUT!!!
A scrapped cell phone I opened here uses the "X" prefix for crystals!!!
Thanks a lot! I hope you're all confused now...
A ceramic resonnator tends to have 3 pins though some only have 2. A
resonnator behaves differently from a crystal in that it tends to
exhibit a broader frequency bandpass characteristic than a crystal.
Ceramic resonnators are also much more sensitive to temperature.
Ceramic resonnators are sometimes used in oscillators to set the
frequency when it isn't too critical, for example in a remote control.
The ceramic resonnator costs much less than a similar crystal. Generally
when a resonnator is not used in an oscillator the wide bandpass is
often desirable and thus substituting a crystal may adversely affect the
circuit because its Q is so much greater. It depends on the circuit.
MB> From: et...@FreeNet.Carleton.CA (Michael Black)
MB> DaveC (dave-us...@mailblocks.com) writes:
> On Sat, 16 Aug 2003 15:15:02 -0700, Asimov wrote
> (in message <MSGID_1=3a167=2f133.0_...@fidonet.org>):
>
>> "Andrew Rossmann" bravely wrote to "All" (16 Aug 03 07:52:40)
>> --- on the topic of "Re: "Y1" component designation?"
>>
>> I don't thing the Y prefix is for a crystal. >>
>
> Now I (OP) am confused. It's not a crystal. I thought a ceramic resonator has
> only 2 leads, while a filter has more(?)
>
> But you say (I think you did...) that it is a filter.
>
> Can you clarify a little?
MB> I'm pretty sure I've seen Y1 to denote crystals, but for the life of
MB> me I can't be certain. Of course! If nowhere else, the ARRL used Y1
MB> to denote a crystal. Bill Orr's Radio Handbook used the same prefix.
MB> Now, I'm not sure the circuit board designator would differentiate
MB> between a crystal and a ceramic resonator. But since I just scrapped
MB> a bunch of boards last week, I don't have anything handy to check.
MB> So I think a manufacturer might use X or Y for the crystal, but
MB> whatever they used, they'd use it for ceramic resonators.
MB> Now for the issue of "filter". A lot of these oscillators use a pair
MB> of capacitors from each side of the crystal (or ceramic resonator)
MB> to ground:
MB> ------|Y1|---------
MB> | |
MB> C1 C2
MB> |________|
MB> ground
MB> Not all oscillators, just the type you often see in digital equipment.
MB> You'd need them whether Y1 was a crystal or a ceramic resonator.
MB> Now, since that's the case, and ceramic resonators can include them,
MB> you can get ceramic resonators with those two capacitors built in.
MB> I would not call it a filter, but it would have three leads (the
MB> middle one being ground). If you put one of those in where the
MB> capacitors were already in place, you might not get good oscillation.
MB> There are of course little ceramic things with three leads that are
MB> indeed filters, as in IF filters. You can use those in oscillators,
MB> I've seen circuits that sort of amount to novelty, but they are not
MB> the same thing as the ceramic filters with the built in capacitors.
MB> Now, if I remember your original post, it sure sounds like a ceramic
MB> resonator. I'd say they are interchangeable with crystals (or vice
MB> versa), given the issue of those external capacitors. If the
MB> circuit expects a resonator with the capacitors, the crystal will
MB> require external capacitors (because they will not be built in).
MB> Ceramic resonators are cheaper to manufacture than crystals, and
MB> not as good in performance as crystals. But for many applications,
MB> the ceramic resonator is fine. Putting a crystal should be fine,
MB> though the reverse situation might not be suitable (depending on
MB> the specific application). There might be a few places where
MB> the design requires the ceramic resonator, because I gather they
MB> can be varied in frequency by changing load capacitors, more than
MB> the average crystal. But that would be a specific exception.
MB> If the thing has two leads only, then the issue of the extra
MB> capacitors doesn't exist. Pull a crystal of the correct frequency
MB> out of something, and there you go.
MB> Michael
... Is reactance then illusory? No, it just appears that way...
That particular resonator is a favorite among radio amateurs for its low
price and its ability to be pulled from 3.50 - 3.58 MHz, i.e. covering all
of the morse part of the 80 meter amateur band.
Sverre
Oslo Norway
www.qsl.net/la3za
>In article <xpi%a.153222$Ho3.18533@sccrnsc03>, tomwo...@comcast.net
>says...
>> it is a crystal or ceramic resenator, possibly 3.58mHz
>
> This makes me wonder: Where did some of these letter designations come
>from? Why are most IC's labeled U1, U2, etc..? I'm guessing Y is from
>crYstal? How about L (or sometimes E) for inductors? Q for transistors?
I seem to recall the letter U was used to denote an unrepairable, replacement
only circuit.
Alan Harriman
What you must mean to say is "3.58 megacycles per second". Without
the additional bit, it technically means nothing, because it does not
specify the period during which all those cycles are counted.
When Megahertz were introduced, it was defined as including the "per second"
bit, making it unnecessary to spell it out.
Michael
And then there's K vs. RY for relays... U vs. IC for integrated circuits...
> A ceramic resonnator tends to have 3 pins though some only have 2.
I could be wrong, but I was led to believe that resonators have two, and
ceramic filters have three.
Back when they introduced it, it seemed very pedantic to a lot of us.
We said "cycles" but we knew we were referring to "cycles per second".
CTSJ> From: "Clifton T. Sharp Jr." <cli...@clifto.com>
CTSJ> Asimov wrote:
> A ceramic resonnator tends to have 3 pins though some only have 2.
CTSJ> I could be wrong, but I was led to believe that resonators have two,
CTSJ> and ceramic filters have three.
Thanks, you are right there, I mixed the 2 a bit, though I think the
main difference between them is that a ceramic filter simply gets an
extra pin attached to it. I experimented with this and found a filter
will work as a resonnator if the middle pin is just left floating.
However, I don't recall if the design frequency was affected. Does it?
Asimov
******
... I worked hard to attach the electrodes to it.
>> There are no caps in this oscillator circuit. The resonator has a 33 ohm
>> (or 22; I can't tell if those are red or orange stripes) resistor
>> connecting each of its 2 pins to ground.
Clifton T. Sharp Jr.:
> That really really really sounds like 33 pF caps to me. Are those "resistors"
> the same color as the other resistors on the PCB?
No, they're bright green. Are they caps? I presumed because they're the same
size as a 1/4 watt resistor and they use the resistor color code that they
are resistors. Is this "duck" not a duck?
Michael
Definitely not a duck. Those have to be caps.
If they're resistors, then the circuit dosen't work.
"L" was for the magnetic Linkage between the turns of a coil. (I remember
that from an old Navy training film.) I haven't seen 'E'.
I think "U" for ICs came from the fact that when you count the pins on an
IC, you follow the shape of a U.
Q came from the shape of a TO-5 transistor can when viewed from the top. It
was a metal cylinder with a rim on the bottom (sort of like a hat) and a
small tab sticking out close to the emitter lead. Viewed from the top, the
can formed the "O" shape and the emitter tab made it into a "Q".
As someone else noted, lots of variations have appeared over the years for
some of the newer components.
--
Neil Preston
npreston at geocities dot com
"Andrew Rossmann" <andysnewsreply@no_junk.comcast.net> wrote in message
news:MPG.19a7e5167...@news.comcast.giganews.com...
>> If I have a difficult time finding a replacement ceramic resonator, can I
>> replace it in this circuit with a crystal? Are they directly compatible?
Sverre Holm:
> The ceramic resonators are usually cheaper than crystals, see eg.
> <http://www.mouser.com/index.cfm?handler=displayproduct&lstdispproductid=311
> 096&e_categoryid=28&e_pcodeid=6484> $0.45, so there is no need to try to
> replace it [with a crystal].
---
I'm having a tough time finding a ceramic resonator locally. I know I can
find one on-line and mail-order. But I want to fix this *now*.
Can I replace a resonator *directly* with a crystal? Any modifications needed
to the circuit?
I know some microcontrollers can use either a resonnator or a crystal as
reference timing element for generating the internal clock. The
difference perhaps has to do with the gain required to make either
oscillate.
Since a crystal has a much higher Q it will accordingly require much
less gain to make the circuit oscillate. OTOH a circuit that has less
gain might not oscillate with a ceramic resonnator.
I've experimented with BFO oscillators that pulled easily using those
little 455KHz cube ceramic resonnators and they worked just great.
A crystal would have been huge by comparison and very hard to pull.
Da> From: DaveC <dave-us...@mailblocks.com>
Da> I'm having a tough time finding a ceramic resonator locally. I know I
Da> can find one on-line and mail-order. But I want to fix this *now*.
Da> Can I replace a resonator *directly* with a crystal? Any modifications
Da> needed to the circuit?
Da> Thanks,
Da> --
Da> Dave C.
Da> dave-us...@mailblocks.com
... Reactance: your imaginary friend.
Beware the faulty memory, but if I recall right a filter can have more
than one resonator element. I suspect the caps might have a small effect
(there's a cap from each resonator lead to the common IIRC) but it
shouldn't throw things off wildly; if you were going for that much
precision you'd have used crystals. :)
I have a feeling most of your resistors are kinda beige, no? Crystals are
high-impedance gizmos, I suspect they wouldn't be happy with 33 ohms
attached. However, I do see 22 to 33 pF caps in many crystal circuits.
Bet they measure open on an ohmmeter (out of circuit, of course).
> "Andrew Rossmann" bravely wrote to "All" (16 Aug 03 07:52:40)
> --- on the topic of "Re: "Y1" component designation?"
>
> I don't thing the Y prefix is for a crystal. Like was stated I thought
> it was for a resonnant filter, i.e ceramic or other type. These tend to
> have 3 legs instead of a crystal's 2.
>
I have an old 1970 ARRL Handbook and it has crystals listed as Y. I
also have a 2002 handbook and it has crystals and ceramic resonators
listed as Y. To me, anything with a Y designation is a resonant
component that is either a crystal or ceramic resonator.
--
Daniel Rudy
Remove nospam, invalid, and 0123456789 to reply.