audio recording on IC -help wanted

[Donald]

Ian Bell wrote:

I have a few tubes of NOS Z8 micros (40 pin DIP) which are mask ROM types
containing a Tiny Basic. You can just hook them up to a terminal and code
directly. Alternatively you can add external ROM and RAM for bigger
programmes.

Anyone interested in these or should I just bin them?

Ian
Donate them to a community college.

They will have fun with the ancient technology.

 

[P.]

On Fri, 12 May 2006 06:57:22 +0100, Ian Bell <ruffrecords@yahoo.co.uk>
wrote:

I have a few tubes of NOS Z8 micros (40 pin DIP) which are mask ROM types
containing a Tiny Basic. You can just hook them up to a terminal and code
directly. Alternatively you can add external ROM and RAM for bigger
programmes.

Anyone interested in these or should I just bin them?

Ian

How many do you have?

Pietr

 

Ian Bell wrote:

I have a few tubes of NOS Z8 micros (40 pin DIP) which are mask ROM types
containing a Tiny Basic. You can just hook them up to a terminal and code
directly. Alternatively you can add external ROM and RAM for bigger
programmes.

Anyone interested in these or should I just bin them?

Ian

what is it and how much???
will it work on my dell 410 workstation

 

[richard mullens]

Ian Bell wrote:

I have a few tubes of NOS Z8 micros (40 pin DIP) which are mask ROM types
containing a Tiny Basic. You can just hook them up to a terminal and code
directly. Alternatively you can add external ROM and RAM for bigger
programmes.

Anyone interested in these or should I just bin them?

Ian

I have one of those chips - and therefore would appreciate a back up.

I also have one from Micromint programmed with Forth.

I am not sure if the code would easily move to a modern flash programmable Z8, nor if those devices have enough ram to make it a
worthwhile undertaking.

I'm in the UK as you probably know.

Richard

 

[ian field]

"Lostgallifreyan" <no-one@nowhere.net> wrote in message
news:Xns97CBA580A3EDClostgallifreyangmail@140.99.99.130...

Alex Coleman <no@no-email.com> wrote in
news:Xns97CB306DB341B71F3M4@127.0.0.1:

Does the gold plating on various plugs and sockets (jacks, phono, SCART,
etc) make any real difference?

I notice that on my PC the PCI sockets have a gold color (is this gold
or phosphor bronze or something else?)

On the other hand the jack sockets, USB, D sockets, etc all have tinner
contacts.

So is gold significant?

Are othe rmetals more significant?


Gold is significant. While it's not the best conductor, it will maintain a
good connection for a long time if undisturbed. It's not the resistance
that matters, it's the electrical noise of corrosion. That's especially a
problem with low voltage signals from tiny coils where energy output is so
small that you might want the current as well as the voltage to get an
efficient signal from them. When using a 200 ohm input, the resistance of
gold contacts is still insignificant, but the noise of any corrosion won't
be.

On a standard input, greater than 10K or even 100K, a bit of tarnishing
isn't going to matter unless it's so bad that it changes resistance
dramatically in a short time. It's still worth having a very low ground
contact resistance though, to prevent hum loops. It's not only audiophools
who might want to consider this. Ground loops are a royal pain, and a
bit of gold plating is usually a cheaper way to avoid it if you want to
use
the system instead of tweaking it all the time. Just avoid butch-looking
cabkes with go-faster stripes and predatory names.



--
----------------------------------------
http://save.nazanin.googlepages.com/home

Wouldn't a poor earth connection tend to break an earth loop?

 

[Lostgallifreyan]

"ian field" <dai.ode@ntlworld.com> wrote in
news:AYlcg.6938$_04.5102@newsfe1-gui.ntli.net:

"Lostgallifreyan" <no-one@nowhere.net> wrote in message
news:Xns97CBA580A3EDClostgallifreyangmail@140.99.99.130...
Alex Coleman <no@no-email.com> wrote in
news:Xns97CB306DB341B71F3M4@127.0.0.1:

Does the gold plating on various plugs and sockets (jacks, phono,
SCART, etc) make any real difference?

I notice that on my PC the PCI sockets have a gold color (is this
gold or phosphor bronze or something else?)

On the other hand the jack sockets, USB, D sockets, etc all have
tinner contacts.

So is gold significant?

Are othe rmetals more significant?


Gold is significant. While it's not the best conductor, it will
maintain a good connection for a long time if undisturbed. It's not
the resistance that matters, it's the electrical noise of corrosion.
That's especially a problem with low voltage signals from tiny coils
where energy output is so small that you might want the current as
well as the voltage to get an efficient signal from them. When using
a 200 ohm input, the resistance of gold contacts is still
insignificant, but the noise of any corrosion won't be.

On a standard input, greater than 10K or even 100K, a bit of
tarnishing isn't going to matter unless it's so bad that it changes
resistance dramatically in a short time. It's still worth having a
very low ground contact resistance though, to prevent hum loops. It's
not only audiophools who might want to consider this. Ground loops
are a royal pain, and a bit of gold plating is usually a cheaper way
to avoid it if you want to use
the system instead of tweaking it all the time. Just avoid
butch-looking cabkes with go-faster stripes and predatory names.



--
----------------------------------------
http://save.nazanin.googlepages.com/home

Wouldn't a poor earth connection tend to break an earth loop?

Yes. I made an error..

What I was remembering is that if you're using a transducer coil with low
impedance input, and have a less than excellent ground, some of the crap
the ground should be carrying will be put through the input and amplified.

To some extent that's true even with a 10K input, so it's best to make all
grounds as good as possible unless you really want to make a ground-lift
resistance to cure a hum loop. Gold plated contacts don't have to be
expensive, and it is worth buying a bulk set for a discount if you're
setting up a load of connections that you don't want to have to watch.

I normally use standard Neutric jacks where possible, for value and good
results I don't know any way to beat them, but I could use a few with a
good gold plate on them.

--
----------------------------------------
http://save.nazanin.googlepages.com/home

 

[CheapscateDave]

I would get a 1.5 amp wall wort to power the relays and use some NPN
transistors as relay drivers. There are even IC circuits if you don't
want to use transistors. This may be cheaper than buying new relays.
Dave

 

[CheapscateDave]

http://www.google.com/search?hl=en&q=ULM2003&btnG=Google+Search

 

mike_l_rossREMOVE@REMOVEsbcglobal.net wrote:

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

--

Hi, Mike. In order to get that kind of current rating, you need some
distance between the contacts, thus more power to pull them in. I
don't believe the beastie you're looking for exists.

The best solution might be to go with some solid state relays. They'll
require only a few mA to drive the internal opto-triac LED, and many
can be driven directly from the AVR pin.

If you gotta have relays for some reason, and you've got some AVR pins
to spare, you might want to look into magnetically latching relays.
The magnetically latching relay has two coils -- one to set, and one to
reset. Although they'll require more current than you can afford, each
coil only has to be pulsed (100ms. or so) to change the relay state.
You can use a resistor to slowly charge a local cap, which can be used
for the coil power to turn on or off the relay, like this (view in
fixed font or M$ Notepad):
|
|VCC
| +
| | ___ More relays
| '-|___|-o------o--o-----o--o----->
| R | | |RY1A | |RY1B
| +| - C| - C|
| C --- ^ C| ^ C|
| --- | C| | C|
| | | | | |
| | '--o '--o
| === | |
| GND |/ |/
| -| -|
| | |> | |>
| .-. | .-. |
| | | | | | |
| | | === | | ===
| From AVR '-' GND '-' GND
| | |
| >-------------' |
| >----------------------'
|
(created by AACircuit v1.28.5 beta 02/06/05 www.tech-chat.de)

Latching relays are sensitive to vibration, and obviously don't turn
off by themselves at power down, but your description indicates that
might not be too much of a problem.

But still, SSRs seem to be your best bet.

Good luck
Chris

 

[Phil Allison]

<mike_l_rossREMOVE@REMOVEsbcglobal.net

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.

** For heaven's sake - add a darn relay driver IC !




........ Phil

 

[Sal Brisindi]

mike_l_rossREMOVE@REMOVEsbcglobal.net wrote:

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

Hi Mike,
Why don't you use a optoisolator and a triac. Much cheaper than a relay
and will use hardly any current to switch them on/off.

Regards,
Sal Brisindi
http://www.tuberadios.com

 

Mike, at first I believed you were out of luck, but tonight in my
Newark Electronics catalog I ran across this interesting little number:

Siemens RY610005, Coil current 44.0 ma., coil resistance 113-ohms,
contact rating 8A at 250VAC, Price in quantities from 1-99 is $3.15.
Seems perfect for a 5V power relay..

This is likely a 1999 price (Catalog 117), but you can likely check it
out on www.newark.com.(Damn, if this thing existed years back, think of
the lives all all of the 2N2270 relay drives whose lives could have
been saved!

Good luck.

Harry C.

-----------------------------------------------------------------------------------------------------------------------------
mike_l_rossREMOVE@REMOVEsbcglobal.net wrote:

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

--

 

[Sal Brisindi]

mike_l_rossREMOVE@REMOVEsbcglobal.net wrote:

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

Mike,
To get an idea how to connect the optoisolator take a look at this link.

http://users.tkk.fi/~jalapaav/elektroniikka/triac/triac2s.gif

Regards,
Sal

 

[Spehro Pefhany]

On Wed, 31 May 2006 00:08:23 GMT, the renowned
mike_l_rossREMOVE@REMOVEsbcglobal.net wrote:

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

Use a higher voltage relay coil, such as 12V, and get one rated for *a
tungsten load* *at the current you need to operate at*. You will
probably need 1W at least per coil to meet your stated requirements.

Using a low coil current relay on a tungsten load at a rating anywhere
close to the resistive rating is just asking for very short life at
best, and welded contacts at worst.

A typical cheap-ass '30A' (resistive) relay such as the T90 might be
derated to 5A with a tungsten load.

You can easily use triacs, but the disadvantages are severe-- the heat
loss at 10A will be quite large (so big heat sinks to keep the triacs
from failing), and lamps of any size will kill the triac when they
burn out unless you significantly overrate the triac and use a good
fuse.

The only relatively inexpensive one with sufficient ratings that comes
to mind atm is the T92, which has a coil power of around 1.7W for DC
coil units, and costs around $5 US in moderate quantity. Check that
the life is sufficient for your application. Data sheet values for
this item are umm.. 'not necessarily pessimistic'.

Small definite purpose contactors will have longer life, but they are
noisy (acoustically and electrically) and are generally nasty beasts.

 

[K `Sleep]

I do know of really cheap, inexpensive switching transistors that can
drive practically any small relay you will find... called a 2N2222 or
2N3904.

<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

--

 

[Phil Allison]

<mike_l_rossREMOVE@REMOVEsbcglobal.net

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.

** For heaven's sake - add a darn relay driver IC !


AND DO NOT RESTRICT REPLIES LIKE YOU HAVE !!!!


ARRRRRRRRRGGGGGGGGHHHHHHH !!!!





........ Phil

 

[ehsjr]

mike_l_rossREMOVE@REMOVEsbcglobal.net wrote:

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 didn't mention the voltage. An Omron G6RN-1A-12 will carry
up to 8 amps resistive at 250 VAC and needs only 18.3 mA at 12
volts. The 5 volt version of that relay takes 44 mA.
Mouser part # 653-G6B-1114P-DC5 is an Omron 5 V coil, 40 mA
SPST that will carry 5 amps resistive at 250 VAC

Is there a reason you can't use a driver transistor with your
Tyco relays? That's the cheapest solution.
Ed

 

Sal Brisindi wrote:

mike_l_rossREMOVE@REMOVEsbcglobal.net wrote:
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


Hi Mike,
Why don't you use a optoisolator and a triac. Much cheaper than a relay
and will use hardly any current to switch them on/off.

Regards,
Sal Brisindi
http://www.tuberadios.com

Wow, lots of good replies, thanks for all the fine advice. With help from
this group, I found a part at DigiKey, an Omron 10A contactor needing only
40 mA to pull on. This was the easiest solution to implement, not
necessarily the best way to go, but I think it will work. I'm hoping that
derating by half will be sufficient to drive 5A of HPS lighting without
trouble. Thanks to all.

Mike Ross


--

 

Mike, Siemens as a line of PC board mounted relays that draw 44 ma at 5
Volts, and can switch 8 Amps @120V. They're priced in the $3.00 range.
(I found them in the Newark Electronics catalog.

If you would like the model numbers and more specifics, post a
followup.

Harry C.


mike_l_rossREMOVE@REMOVEsbcglobal.net wrote:

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

--

 

[Tim Auton]

mike_l_rossREMOVE@REMOVEsbcglobal.net wrote:

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.

Are you sure about that 40mA spec? That's the limit per pin in the AVR
datasheets I've got to hand, but there are other limits - on total
current on Vcc and GND and for various combinations of ports. For
example, with the ATmega 128, there's total limit of 400mA in or out
(you need 480mA for 12 40mA relays), and further limits depending on
which ports you planned to use. Check the notes in the Electrical
Characteristics section of the datasheet carefully.

I'd go for an IC to drive the relays. You can get your freewheeling
diodes built-in and enough drive for whatever relays you fancy,
without stressing the AVR's outputs. No more soldering or board space
then the diodes alone and it may even pay for itself by allowing you
to choose from a wider range of relays.


Tim
--
Did I really still have that sig?