audio recording on IC -help wanted

[DaveM]

<mike_l_rossREMOVE@REMOVEsbcglobal.net> wrote in message
news:X75fg.88483$H71.86022@newssvr13.news.prodigy.com...

I'm trying to use my little AVR to control up to 12 120VAC loads, up to 5
amps. Does anyone know of a cheap (< $5 US) relay (SPST-NO) that only
needs 40 mA or less to activate? My Tyco T77 relays need 90 mA at 5VDC to
pull in the contacts, it turns out, so the processor dies. The lowest I've
found on-line is 60 mA. I don't have a harsh environment, or rapid
switching requirements, just need a simple on-off relay. I'm switching
banks of lights, should look cool if I can get it to work. Thanks for any
advice.

Mike Ross

--

I don't think you need low power relays... your money would be better spent on a
proper interface between the AVR port and the relays. A simple transistor
between the AVR output and the relay would let you use your existing relays and
would amount to a few cents per relay.
You didn't indicate whether the AVR output is high or low when the relay should
turn on, so first, I'll assume that it's low. In that case, use a PNP
transistor (such as a 2N2907). Connect it as such:

Please view in a fixed-width font such as Courier.


+----------+ +5V
| | |
| | |
| AVR | |
| | |
| | |
| | | E
| | 10K /
| | +------+ |/
| +--------+ +------| 2N2907
| | +------+ B |\
| | \
| | |C
| | |
| | |
| | +-+-+
| | | |
| | | |
| | | | Relay coil
| | | |
| | | |
| | +-+-+
| | |
| | |
| | --+--
| | ---
| | -
+----------+



In case the AVR output is high when the relay should be on,
use an NPN transistor (such as a 2N2222) like this:

+5V
|
|
+-+-+
| |
+----------+ | |
| | | | Relay coil
| | | |
| AVR | | |
| | +-+-+
| | |
| | |C
| | 10K /
| | +------+ |/
| +--------+ +------| 2N2222
| | +------+ B |\
| | \
| | |E
| | |
| | |
| | --+--
| | ---
| | -
| |
+----------+

Total cost per output: about $0.50 US

Cheers!!!!

--
Dave M
MasonDG44 at comcast dot net (Just substitute the appropriate characters in the
address)

Some days you're the dog, some days the hydrant.

 

[Brian]

<mike_l_rossREMOVE@REMOVEsbcglobal.net> wrote in message
news:X75fg.88483$H71.86022@newssvr13.news.prodigy.com...

I'm trying to use my little AVR to control up to 12 120VAC loads, up to 5
amps. Does anyone know of a cheap (< $5 US) relay (SPST-NO) that only
needs 40 mA or less to activate? My Tyco T77 relays need 90 mA at 5VDC to
pull in the contacts, it turns out, so the processor dies. The lowest I've
found on-line is 60 mA. I don't have a harsh environment, or rapid
switching requirements, just need a simple on-off relay. I'm switching
banks of lights, should look cool if I can get it to work. Thanks for any
advice.

Mike Ross

--

You might want to use a MOSFET (like a 2N7000) to drive the relays. Or maybe
a Darlington array, something like the ULN-2803A. This would be easier on
the AVR and also make the relay selection less fussy.
Brian

 

[Brian]

<mike_l_rossREMOVE@REMOVEsbcglobal.net> wrote in message
news:X75fg.88483$H71.86022@newssvr13.news.prodigy.com...

I'm trying to use my little AVR to control up to 12 120VAC loads, up to 5
amps. Does anyone know of a cheap (< $5 US) relay (SPST-NO) that only
needs 40 mA or less to activate? My Tyco T77 relays need 90 mA at 5VDC to
pull in the contacts, it turns out, so the processor dies. The lowest I've
found on-line is 60 mA. I don't have a harsh environment, or rapid
switching requirements, just need a simple on-off relay. I'm switching
banks of lights, should look cool if I can get it to work. Thanks for any
advice.

Mike Ross

--

You might be better off using transistors, mosfets (like a 2N7000) or a
Darlington array (like a ULN-2803A) to drive the relays. It would be easier
on the AVR and it would probably be easier to find lower priced relays.
Brian

 

[Richard The Dreaded Liber]

On Sat, 17 Jun 2006 18:56:19 +0000, John B wrote:

ian field scrobe on the papyrus:
"Richard The Dreaded Libertarian" <null@example.net> wrote in message
On Fri, 16 Jun 2006 07:02:24 +0000, Michael A. Terrell wrote:
Richard The Dreaded Libertarian wrote:

My platform is a little radical:
1. Fire the IRS, and make ALL taxes voluntary.
2. End the USA's insane crusades, and find something to do with
all of
that military crap.
3. Reinstate the Constitution as written.

But, what the hey, it might get attention!

If you got any media coverage you'd soon be in an insane asylum.
;(

Well, John F and Michael A T hate me - anybody else want to
reinforce this impeccable endorsement? :-D

Thanks!
Rich


............................even your rubber chicken hates you!

Hey, I'll hate you too if you like. I only charge 10 bucks an hour for
hating, consultancy costs a bit more.

Well, I'm certainly not going to _pay_ you! (until I win the lottery, when
I'll have a whole bunch for kickbacks to campaign workers. ;-) )

It's just that, being the radical libertarianoid that I am, it's a strong
endorsement being hated by ultra-right-wing neocon nazi wannabes.

Are you an ultra-right-wing neocon nazi wannabe? If so, then I shouldn't
_have_ to pay you to hate me! ;-D

Cheers!
Rich

 

[Jenalee K.]

Eeyore wrote :

Joel Kolstad wrote:

"Jenalee K." <jenaleek@yahoo.com> wrote in message
news:1151501177.390950.124560@d56g2000cwd.googlegroups.com...
To make a non-volatile software programmable DIP switch. Anyone? Like
those non-volatile digital potentiometers.

How many DIP switches do you need? You can cheat and use those digital pots
if you don't need too many:
http://www.maxim-ic.com/appnotes.cfm/appnote_number/238

If you're looking for something that functions as a switch for routing signals
around even when no power is available, there are some RF SPDT switches
that'll still pass a signal from one input to one output or the other with no
power applied -- they use something like a MOSFET and trap charge to keep the
channel around without power.

How about latching relays ?

Graham

Latching relays (price?) could work but I'd have to add circuitry to
read back the actual position.

Thanks,
Jenalee K.

 

[Tony Williams]

In article <44a8ebdc$0$29125$9b4e6d93@newsread4.arcor-online.net>,
Tilmann Reh <tilmannreh@despammed.com> wrote:

does anyone have a datasheet of the MM5740 keyboard encoder,
formerly made by NSC (around the late 70s)? It was used in early
versions of the Apple II, but later replaced by another encoder
since it became obsolete...

Not a data sheet, but the MM5740 is mentioned and
drawn in a PROM application brief ( 4 pages) in
the NatSemi Memory Applications Handbook (1978).
There is a hint that it is a precis of an app note,
AN-80, "MOS Keyboard Encoding" by Dom Richiuso.

--
Tony Williams.

 

[Tilmann Reh]

Tony Williams schrieb:

does anyone have a datasheet of the MM5740 keyboard encoder,
formerly made by NSC (around the late 70s)? It was used in early
versions of the Apple II, but later replaced by another encoder
since it became obsolete...

Not a data sheet, but the MM5740 is mentioned and
drawn in a PROM application brief ( 4 pages) in
the NatSemi Memory Applications Handbook (1978).
There is a hint that it is a precis of an app note,
AN-80, "MOS Keyboard Encoding" by Dom Richiuso.

I have neither that handbook nor that app note...

Could you provide it (as fax or scan), in case noone else has the data
sheet?

Thanks,

--
Dipl.-Ing. Tilmann Reh
http://www.autometer.de - Elektronik nach Maß.

 

[Lostgallifreyan]

diplome333@hotmail.com wrote:

hi !

I have a problem.... i don't understand...help me please !!!
http://www.animals-superstars.com/photo-109260.html

Tank you

Patate069

Yep. I can safely agree, you have a problem.

 

[Tony Williams]

In article <44a91623$0$26272$9b4e6d93@newsread2.arcor-online.net>,
Tilmann Reh <tilmannreh@despammed.com> wrote:

Could you provide it (as fax or scan), in case noone else has the
data sheet?

Email your snailmail address.

I'll just slice the pages out and post them.

--
Tony Williams.

 

[David L. Jones]

gitproinc@yahoo.com wrote:

Quality Manager needed on Full Time basis near south of Los Angeles -
CA

A. Must have a Bachelor in Engineering and experience in hard floor
production management
B. Degree or diploma in Statistical quality control
C. Must have idea of some these regulations :-

ISO9002, CSA, ATEX, EC Directives, FDA regulations

Our client is one of the world's most reputed instrumentation company
with $1B+ global revenue. Their US division is in Anaheim, California.
Occasional international and national travel is required.

reply to recruiter@gitpro.com

or contact

Sree

GITPRO INC.
Cell : (901) 339-9838
Fax : (413) 725-3576

You forgot another requirement:
- Must be willing to work for someone stupid enough to post to the
wrong newsgroups.

Dave

 

[GB]

"David L. Jones" <altzone@gmail.com> wrote in news:1152156272.553938.238250
@j8g2000cwa.googlegroups.com:

gitproinc@yahoo.com wrote:
Quality Manager needed on Full Time basis near south of Los Angeles -
CA
[...]
Our client is one of the world's most reputed instrumentation company
with $1B+ global revenue. Their US division is in Anaheim, California.
Occasional international and national travel is required.
You forgot another requirement:
- Must be willing to work for someone stupid enough to post to the
wrong newsgroups.

Er, must be wiling to work for someone stupid enough to hire someone
from a pimp who's stupid enough to post to the wrong newsgroup.


GB, my bullshit detector tells me that the post is from a pimp, not
an actual employer. Truth be known the job doesn't even exist.
--
"Men will never be free until the last king is strangled with the
entrails of the last priest." (Diderot, paraphrasing Meslier)

 

[David L. Jones]

GB wrote:

"David L. Jones" <altzone@gmail.com> wrote in news:1152156272.553938.238250
@j8g2000cwa.googlegroups.com:
gitproinc@yahoo.com wrote:
Quality Manager needed on Full Time basis near south of Los Angeles -
CA
[...]
Our client is one of the world's most reputed instrumentation company
with $1B+ global revenue. Their US division is in Anaheim, California.
Occasional international and national travel is required.
You forgot another requirement:
- Must be willing to work for someone stupid enough to post to the
wrong newsgroups.

Er, must be wiling to work for someone stupid enough to hire someone
from a pimp who's stupid enough to post to the wrong newsgroup.

Doh, of course!

GB, my bullshit detector tells me that the post is from a pimp, not
an actual employer. Truth be known the job doesn't even exist.

It is indeed from a pimp. Good to see they are at least trying to do
something for their measly 25% of your first years salary commission. I
live in eternal hope that one day I'll actually meet a "recruitment
consultant" that actually has a clue. I'll settle for half a clue, but
alas I just don't think it's obtainable.

Dave

 

[JeffM]

was: Cell Phone Information Site

Chris wrote:
>[SPAM[

 

[Ross Herbert]

On Mon, 17 Jul 2006 22:16:50 -0500, "Eric Schmitt"
<erics.pinball@gmail.com> wrote:

are there a difference between the two?

2n222
2n222a

can they be interchanged?

please send me a direct e mail,

thanks for reading!!

--Eric

I think you mean 2N2222...

From memory the 2N2222 (TO18) has Vceo=30V and the A version has
Vceo=40V. Therefore, you can use the A version in place of the 2222
but not necessarily the other way round. If Vce supply voltage is less
than 30V then either will do.

 

[JeffM]

was: Great website - Too bad no one sees it G2OG

rfyxuecn @email.adr wrote:
Did I say "SPAMmer"? I meant MEGA-SPAMMER.
http://groups.google.com/groups/search?filter=0&q=tinyurl.com/pzkxe&scoring=d

X-Complaints-To: http://www.ntlworld.com/netreport

 

x-no-archive: yes

These have been relisted for half off.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=190017902392

FA: 20 Motorola MDA1591-3 solid state rectifiers (plus 2 MDA1591-2
rectifiers as a bonus).

See auction listing for photo & diagram

I was told the MDA1591-3 is rated at 200V 4 amps with a 100uS recovery
time.

New old stock (from about 1969-1972) solid state replacements for
tube-type rectifiers used in guitar amplifiers, tube audio amps,
shortwave radios, ham radios, etc.

Non-US buyers must pay by PayPal and include additional amont for
postage.

NOTE: I don't have the data sheet for this, but I did verify the
diagram. If you happen to have an old Motorola Master Index or Master
Selction Guide that has the data for this, I would appreciate a scan or

a link. Any data is helpful.

Please e-mail with any questions. Thanks very much!

other keywords: octal base diode Moto n.o.s. solid-state

 

[Jim]

Did you warn buyers about increased B+, need to rebias, and possible
over voltage on electrolytics?

prototech@usa.net wrote:

x-no-archive: yes

These have been relisted for half off.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=190017902392


FA: 20 Motorola MDA1591-3 solid state rectifiers (plus 2 MDA1591-2
rectifiers as a bonus).

See auction listing for photo & diagram

I was told the MDA1591-3 is rated at 200V 4 amps with a 100uS recovery
time.

New old stock (from about 1969-1972) solid state replacements for
tube-type rectifiers used in guitar amplifiers, tube audio amps,
shortwave radios, ham radios, etc.

Non-US buyers must pay by PayPal and include additional amont for
postage.

NOTE: I don't have the data sheet for this, but I did verify the
diagram. If you happen to have an old Motorola Master Index or Master
Selction Guide that has the data for this, I would appreciate a scan or

a link. Any data is helpful.

Please e-mail with any questions. Thanks very much!

other keywords: octal base diode Moto n.o.s. solid-state

 

[Mark Fortune]

ian field wrote:

You can't beat a microwave oven transformer with a secondary transplant!

And I see plenty of old microwaves just laying out on the street
destined for the scrap heap around here. thanks for the idea.


Mark

 

[Ross Herbert]

On Tue, 08 Aug 2006 19:20:01 +0100, Mark Fortune <mark@fortrex.co.uk>
wrote:

Greetings to the collective.

For my next project I want to build a bench power supply and do away
with this old switch mode AT computer PSU that i'm currently using.

The design I have in mind will be pretty beefy, giving a wide range of
fixed and variable output voltages (i'm thinking from -50v up to +50)
and deliver up to 5amps of current. if my estimates are right i'll need
a 600va+ (100v * 5a + overhead) transformer to do the job well. Now i've
had a look at some transformers in this range, and they're a little out
of my price range. so now i'm considering building my own.

The specifications I need are as follows:

primary: 0-230v @ 50Hz
Secondary: 60v-0-60v
secondary output current max: 5A

I have an intermediate understanding of transformers, but have never
actually built one, hence I am seeking advice from those with experience
in this field.
So where do I start? what type of core is best for this application? - I
have a friend who's blasting off that toroids are best, but i'd like a
second opinion, and what kind of wire to use for the primary and
secondaries? what are good safety practices regarding insulation? Is
this even a feasable project to undertake (moreso on the money side than
timewise). Any other advice also greatly appreciated.

regards,
Mark

I admire your desire to have a go at such a large project, although I
have to ask if you are really all that keen to learn transformer
design.

An old (now deceased) engineer friend of mine was gun at designing
transformers and even he required about 3 iterations to get the design
right for maximum efficiency. And he wasn't designing anything quite
as big as you are after. A 350VA transformer isn't all that small
especially if you are using other than a toroidal core, and those are
a bugger to wind by hand.

Quite frankly, I don't think the exercise is all that worthwhile
unless you plan to use the expertise gained in the future. Transformer
design and building is somewhat a "black art" and you can easily get
bogged down. If you really only want to design and build a bench PSU
then this exercise in itself would be an achievemnt to be proud of.
But you don't want to spend 6 months building transformers before you
get to the rest of the design.

 

[Phil S.]

"Jim" <askme@beforeyousend.com> wrote in message
news:12dffe69fon0idb@corp.supernews.com...

Did you warn buyers about increased B+, need to rebias, and possible over
voltage on electrolytics?

Jim, I think these things on going to blow on most amps we know. They are
rated at 200V. Even the FrankenVox thing I just built has B+ in the upper
200's. These are probably useless for our crowd. Nifty lookin', though.

prototech@usa.net wrote:

x-no-archive: yes

These have been relisted for half off.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=190017902392


FA: 20 Motorola MDA1591-3 solid state rectifiers (plus 2 MDA1591-2
rectifiers as a bonus).

See auction listing for photo & diagram

I was told the MDA1591-3 is rated at 200V 4 amps with a 100uS recovery
time.

New old stock (from about 1969-1972) solid state replacements for
tube-type rectifiers used in guitar amplifiers, tube audio amps,
shortwave radios, ham radios, etc.

Non-US buyers must pay by PayPal and include additional amont for
postage.

NOTE: I don't have the data sheet for this, but I did verify the
diagram. If you happen to have an old Motorola Master Index or Master
Selction Guide that has the data for this, I would appreciate a scan or

a link. Any data is helpful.

Please e-mail with any questions. Thanks very much!

other keywords: octal base diode Moto n.o.s. solid-state