audio recording on IC -help wanted

[Dave Platt]

In article <7b467360.0502091300.3761ec14@posting.google.com>,
Dave <blaildyors@quassouwko.mailexpire.com> wrote:

Could anybody with a copy of towers etc. give me an equivalent for a 2N3904

That part can probably be accurately described as a "jellybean" - it's
an NPN switching transistor, Ft 300 MHz, good up to an absolute limit
of 40 volts and 200 mA.

They're quite common and easy to come by, I believe. If you can't
find one, then unless there's something exotic about your application
you can probably substitute a PN2222A. 2N4401 might also work (Ft is
a bit lower), and I have no doubt that there are a zillion other
substitutes which would work OK in many circuit applications.

--
Dave Platt <dplatt@radagast.org> 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!

 

[James Sweet]

"dave" <tool_box@weirdstuffcox.net> wrote in message
news:KBsOd.106215$Jk5.93313@lakeread01...

Jerry G. wrote:
Take a look inside, and see!

I would, but first I'd have to travel and hour and a half ONE way just
to find out - still hope someone here might know what's inside 'em
"generally"....before I make a long trip...

do you know, jerry?

thanks,

box :-\

Aside from the batteries, usually a MASSIVE 60Hz transformer, a bunch of big
MOSFETs or bipolar power transistors, and some assorted logic.

 

[Michael Black]

Hal Murray (hmurray@suespammers.org) writes:

Most special order crystal oscillator packages now have a
PLL in them. When you order a special frequency, they take
an unprogrammed unit off the shelf and program in the PLL
parameters. Delivery in a few days.

The problem is that you get the jitter specs of the PLL rather than
the crystal. The jitter turns out to be important for high speed A/D
applications. It's probably important in most RF work too.

Anybody know a good place to get real crystal oscillators made to order
in small volumes? I need 10 or 20 but the first try came up with
a min order of 250. I'm expecting 10-12 week delivery. I can live
with that.

Many crystal/oscillator companies used to be in the business
of making small runs to a specified frequency. How many are
left?


You're complicating matters by insisting on an actual oscillator.

An oscillator is really simple, so there's not a lot of advantage to
buying an oscillator module, certainly not if they are giving you problems.

You aren't likely to get custom frequency oscillator modules, because
they will be too costly to manufacture unless you are buying large quantities.
The modules you've seen are a tradeoff, allowing a wide range of frequencies
without the manufacturing cost. But they have to use a synthesizer, because
otherwise they are dealing with crystal grinding, and that's where the cost
lies.

Just order crystals. Newcomers don't realize that up till thirty or
so years ago, except for a handful of frequencies, crystals were not a
commodity. They were ground on demand, and of course you paid for them.
The only mass-produced crystals were for frequencies that were used
a lot.

That hasn't really changed, the crystals you see in the catalogs are
mass produced because they are commonly used frequencies. But those
common frequencies are more numerous now, since digital devices caused
a rise in the use of crystals in electronic equipment.

So if the frequency you want isn't a common frequency, you send the specs
to a crystal manufacturer, and they grind a crystal for you.

Michael

Anybody familiar with the details of the PLL setup? I assume
somebody did the math and figured out what frequencies they
have to stock in order to cover all the target frequencies they
might want to produce. How many different frequencies do they
have to stock? What sort of ratios are they using in the PLL?

When did everybody switch to PLLs?

--
The suespammers.org mail server is located in California. So are all my
other mailboxes. Please do not send unsolicited bulk e-mail or unsolicited
commercial e-mail to my suespammers.org address or any of my other addresses.
These are my opinions, not necessarily my employer's. I hate spam.

 

[Watson A.Name - \"Watt Su]

"dave" <tool_box@weirdstuffcox.net> wrote in message
news:8hMOd.106427$Jk5.58877@lakeread01...
[snip]

thanks for educating me

box

ps-some of the threads below gave me this hairbrained idea ;-).

BTW, it's harebrained.

 

[carl mciver]

"Watson A.Name - "Watt Sun, the Dark Remover"" <NOSPAM@dslextreme.com> wrote
in message news:110ol5rp4f2fi27@corp.supernews.com...
|
| "dave" <tool_box@weirdstuffcox.net> wrote in message
| news:8hMOd.106427$Jk5.58877@lakeread01...
| [snip]
|
| > thanks for educating me
| >
| > box
| >
| > ps-some of the threads below gave me this hairbrained idea ;-).
|
| BTW, it's harebrained.

Are you sure? The meds I've been taking lately...... Definitely fuzzy
in there!

 

dave wrote:
<snipped>
There is no bridge rectifier visible. Nice caps - you'll find
the specs written on the side.

I'm puzzled as to how you're going to build the thing.
Can you follow the threads you cited to put the thing
together?

Ed

 

[Watson A.Name - \"Watt Su]

"Watson A.Name - "Watt Sun, the Dark Remover"" <NOSPAM@dslextreme.com>
wrote in message news:110sfjjoj3k8aeb@corp.supernews.com...

Weird transistor. Its lowest beta starts at where most others max out
on a really hot day. Its max is up there with the Darlingtons. Its
Vce(sat) is measured at Ic:Ib of 100:1.

http://www.ee.nec.de/_pdf/D16197EJ1V0DS00.PDF

Oh, yeah, I forgot to mention that it's used in MORTARS.

Or did they mean motors..

 

[R.Lewis]

"Watson A.Name - "Watt Sun, the Dark Remover"" <NOSPAM@dslextreme.com> wrote
in message news:110sfjjoj3k8aeb@corp.supernews.com...

Weird transistor. Its lowest beta starts at where most others max out
on a really hot day. Its max is up there with the Darlingtons. Its
Vce(sat) is measured at Ic:Ib of 100:1.

http://www.ee.nec.de/_pdf/D16197EJ1V0DS00.PDF

Sounds almost too good to be true.
Anyone out there have user experience of these?

How much do they cost (in 1k lots) ?

 

[James T. White]

"R.Lewis" <h.lewis@connect-2.co.uk> wrote in message
news:3779t7F57k4aqU1@individual.net...

"Watson A.Name - "Watt Sun, the Dark Remover"" <NOSPAM@dslextreme.com> wrote
in message news:110sfjjoj3k8aeb@corp.supernews.com...

Weird transistor. Its lowest beta starts at where most others max out
on a really hot day. Its max is up there with the Darlingtons. Its
Vce(sat) is measured at Ic:Ib of 100:1.

http://www.ee.nec.de/_pdf/D16197EJ1V0DS00.PDF



Sounds almost too good to be true.
Anyone out there have user experience of these?

How much do they cost (in 1k lots) ?


Only supplier reference I could find for this was Mouser and they show it as

"Discontinued/Replaced" with none in stock.

--
James T. White

 

[Watson A.Name - \"Watt Su]

"R.Lewis" <h.lewis@connect-2.co.uk> wrote in message
news:3779t7F57k4aqU1@individual.net...

"Watson A.Name - "Watt Sun, the Dark Remover"" <NOSPAM@dslextreme.com
wrote
in message news:110sfjjoj3k8aeb@corp.supernews.com...

Weird transistor. Its lowest beta starts at where most others max
out
on a really hot day. Its max is up there with the Darlingtons. Its
Vce(sat) is measured at Ic:Ib of 100:1.

http://www.ee.nec.de/_pdf/D16197EJ1V0DS00.PDF

Sounds almost too good to be true.
Anyone out there have user experience of these?

How much do they cost (in 1k lots) ?

Here's another one that's almost as high, but rated at higher power, 40W
in the TO-220 package. 2SD1273, 2SD1273A - compl is 2SB1299.

Here's another one almost as high a beta that comes in a smaller
package, lower voltage. 2SD1458

Both are from Matsushita AKA Panasonic.

 

[Frank Moe]

I think it will be difficult to find a manufacturer for only 10 crystals.
Maybe Quarz Technik (www.quarz-technik.de) still makes single custom crystals.
KVG (www.kvg-gmbh.com) also used to accept small quantity orders.
Do you need 10 forever or 10 for first series and 100 later?
Of cause you can have a single one but what would you want to pay?
What frequency are you looking for? Maybe it is not as uncustom as you think...
Frank

 

[Mike Harrison]

On Fri, 18 Feb 2005 09:42:01 -0500, Brian Lyons <Nospam@nowhere.com> wrote:

I need data sheet for Motorola 16K*4 static RAM chip

part number is MCM6290

I have pin out, but need more details. Google search unsuccessful for
DS.

Thanks,

Brian

http://www.alldatasheet.com/datasheet-pdf/pdf/MOTOROLA/MCM62963A.html

 

[Brian Lyons]

On Fri, 18 Feb 2005 16:53:05 GMT, Mike Harrison <mike@whitewing.co.uk>
wrote:

On Fri, 18 Feb 2005 09:42:01 -0500, Brian Lyons <Nospam@nowhere.com> wrote:

I need data sheet for Motorola 16K*4 static RAM chip

part number is MCM6290

I have pin out, but need more details. Google search unsuccessful for
DS.

Thanks,

Brian

http://www.alldatasheet.com/datasheet-pdf/pdf/MOTOROLA/MCM62963A.html

Thanks, but the link takes me to a 44 pin PLCC 4K*10 bit RAM and is
synchronous with external clock (K)

MCM6290 is 24 pin DIP 16K*4 bit RAM and does not use external
clocking.

The MCM6290 is a 1990-1992 era chip, now considered obsolete.

A couple of weeks ago, It seemed like a good idea to use these spare
parts from my junk box, for video memory in a CRT controller that I am
building. Now, I not quite so sure.

Thanks anyway,

Brian

 

[David DiGiacomo]

I have it, but I have no way to mail it to you... oh well...

 

[NSM]

"Beeper" <Beeper@echoes.net> wrote in message
news:cvfuko0cnl@enews1.newsguy.com...

Wrong again! Many times a sub panel is introduced into the picture and you
run an isolated neutral. by Isolated I mean it is not bonded to the ground
strip. This is done because the Ground is not suppose to have current on
it. It is as Terry said a safety device. If you were to bond the neutral
and
ground bars in the sub panel, then the ground would share the current load
back to the main panel.

Where it is grounded.

N

 

[Ross Herbert]

On Fri, 28 Jan 2005 18:01:54 -0800, "aurgathor" <spam-me@if-you.com>
wrote:

"Kim Clay" <kimclay@myrealbox.com> wrote in message
news:c4jjv0hc94hi6mamo3ui5pomt1qr85s298@4ax.com...
On Thu, 27 Jan 2005 11:41:56 -0800, "aurgathor" <spam-me@if-you.com
wrote:

Yesterday I started to charge a car battery that was sitting unused
for quite a while with a 1A charger. (my other one is broke)
Initially, the battery was around 6V,
Three discharged (but not completely) cells = 6V, the other three cells
are at 0.0V each due to internal shorts.

That is not correct. A discharged battery can go down that much,
or even more without the cells having internal shorts. Case in point,
a couple daysbefore this one I had a battery that measured 1.7V!
(in car, with a light left ON). In a couple of days, that battery was
measuring 14V, and worked just fine. I just checked it today --
12.85V.

The most likely scenario is that 3 of the cells were shorted and the
remaining 3 were not shorted BEFORE you commenced charging. The 3
un-shorted cells would however have been high resistance thus causing
the initial voltage reading to be high because the charging current
low. As the 3 un-shorted cells commenced to absorb charge their
internal resistance reduced thus the charging current increased. As
the charge on these cells reached 6.6V (approx) they would still have
taken nearly the maximum available current from your 1A charger and
this item would have been very hot.

Based on the voltage measurements after a few hours of charging
(10.40V -> 8.40V -> 6.40V) some cells must've become shorted
during the charging process. Alas, I no longer remember the voltage
after the first 10 - 15 mins of charging -- that may have been close to 12V.

No... these cells were already shorted before charging commenced.

Because (from your first sentence) "battery that was sitting unused
for quite a while". Car batteries self discharge just sitting on the
shelf. A discharged battery that sits is quickly self destructing
internally, as you have found out.

I expected sulfation, and while that's no good either, it's less
deadly, and it's easier to reverse than an internal short.

Not true. A fully sulfated battery is almost impossible to rectify
even partially.

I guess material fell from the plates, created a highly conductive
sludge in the bottom, and that's what shorted the cells out.

One of my friend got a 100A or so charger, so I wonder if
I can blow the shorts with that. ;-) Of course, I'd need to
find a good enough container first incase the whole battery
blows.

Stupid idea. You just can't BLOW away a build up of sludge at the
bottom of the cells by pumping in excessively high current. For a
start it would destroy any good cells in the process even if we
disregard the hazardous nature of such an action. Even assuming that
you could disturb the sludge and get it to distribute itself
throughout the electrolyte where it no longer shorted the cells, it
would still have to settle somewhere eventually. Guess where it would
settle?

 

et me know how many you need by email. I have them in stock.

My email is removethishs1948@yahoo.com
Remove the "removethis prior to emailing me



Please contact me at this email. I have them in stock


Prior to emailing me remove the "removethis"

removethishs1948@yahoo.com


On Fri, 31 Dec 2004 17:46:03 GMT, Michael <NoSpam@att.net> wrote:

Looking for specs. on HY51C4256S-10 This is an old DIP RAM chip.
I tried the usual suspects including DataSheetArchive.com but no joy.

If I can't find this particular chip, is there a newer, compatible
chip? I have an old printer that would benefit from a few more megs of
RAM.

Tnx,
Michael

 

[Tom Bruhns]

Tim, would a 100MHz oscillator module do for you? See DigiKey
CTX318LVCT-ND, for example.

Cheers,
Tom

 

[Jeroen]

"Don Bruder" <dakidd@sonic.net> schreef in bericht
news:l6KUd.8645$m31.106117@typhoon.sonic.net...

Hiya folks...

Looking for information on a chip out of a radio-controlled car. This
looks to be the receiver/decoder chip. The transmitter contains a
simliar chip, with "RX replaced by "TX" - Obviously, the two chips make
up the heart of the encode-TX/RX-decode circuitry.


Here's everything I've got on the beast

It's a 16 pin SMT DIP
-----------------
| RX6C |
| [logo] A9112 |
| o 1CA |
-----------------

The [logo] makes me think "reindeer with a moustache" - As close as I
can get with ASCII art, it looks something like this:

U U
\_ U _/
\ /
/// RMC \\\

The letters "RMC" are literals - the groups of "///" and "\\\" are more
curved, looking a lot like the ends of a rainbow sticking out from
behind the "RMC".

Anybody know where I can find information about this chip and its pinout?

Google is coming up empty for me on all variations on the
letters/numbers that I try putting in, and RMC returns so many hits I
don't even know where to start - suffice it to say that the first 2
pages worth of results for RMC had nothing that looked even slightly
related to electronics... Metals, casting, plastic model kits,
bearings... But nothing like radio control electronics.

Anybody got any advice?

FWIW: It comes out of a 49 MHz Radio Shack RC car, the so-called
"Dynamos Wicked Wing". (Catalog number 60-4395)

I'm also looking for some assistance in changing the board it's on from
a "car" controller to a digital logic level signal source - IE, If I lay
on the "forward" button, I want "pin 1" to be a logic high, and pin 2 to
be a logic low, and if I hit the "reverse" button, I want "pin 1" to be
low, while "pin 2" goes high. ("pin"s in this case being the final
outputs after any massaging by circuitry I may need to add.)

Probably the chipset is from UMC, but it could be an obscure chinese brand
as well. I think it's impossible to find info on it.

I have dismantled a cheap China made R/C car, which contained a RX7/TX7
chipset in THM. The board contained discrete transistors to drive the motor
and steering solenoid, so the outputs can be found on the chip; a little
scope probing should tell which pin does what.

I wouldn't use this kind of circuit for secure things, e.g. no door openers
or something. Data format is very likely to be very simple, something like
PWM modulation to differentiate between states, e.g. 25% is left, 50% is
right etc.

Jeroen

 

makes me think "reindeer with a moustache" - As close as I

can get with ASCII art, it looks something like this:

U U
\_ U _/
\ /
/// RMC \\\

The logo is meant to represent a crab rendered in vectors, and the
company is Realtek. They used to have the datasheets for this chipset
up in the public areas on their site, but last time I checked it wasn't
findable. You might have better luck. www.realtek.com.tw.

I'm also looking for some assistance in changing the board it's on
from
a "car" controller to a digital logic level signal source - IE, If I
lay
on the "forward" button, I want "pin 1" to be a logic high, and pin 2
to

The output of that chip is practically what you want already. It's a
2-channel non-proportional controller.