"Joerg" wrote in message
m...
Hello John,

Or you can just bend all but the ground pins outward from the base
of
the chip (e.g., www.speakeasy.net/
~jmiles1/ke5fx/492ap/large/close1.jpg). The pins won't break if you
don't flex them more than once or twice.

But then I won't have an excuse to eat another Haagen Dasz bar :-(

You don't need an excuse. We give you permission. ;-)

BTW, you can go to Michaels or other hobby/crafts store and buy a whole
handful of ice scream sticks for a couple bucks. You don't have to wash
'em, then. :-P

Every year the Engineering Club has a model bridge building contest.
They make them out of ice scream sticks. They support the ends of the
bridge on some bricks and suspend a bucket from the middle. Then fill
the bucket with sand until CRACK! the bridge crumples. Pretty neat!

You could come on over afterward and get some free slightly used ice
scream sticks. :-)


Regards, Joerg

http://www.analogconsultants.com

beerbarrel wrote:



For what it is worth, as the others say Ebay is good. I picked up 5
24" by 24" double sided sheets for 20 dollars.

Ditto. You got a better deal than I did. I got 5 sheets about 14x14,
single sided, for 10 bucks.

-Bill

wrote in message
oups.com...
[snip]

Cleaning OLD PCB stock the "green" way -

Sprinkle any kind of table salt on the PCB stock, then take
half a lemon and rub it on the salt. Most of the blackened
oxide will disappear!

I've amazed a few people when we go out to eat lunch. I take a
tarnished golden dollar and put it in the lemon from a drink, or catsup
works just as well. Less than a minute later, it's nice and shiny
again. The vinegar or citric acid reduces all that tarnish to
invisible. Some say the carbonic acid in the fizz in cola will do it,
too, but I haven't tried it. Check it out sometime when you're into
impressing your friends.

I tried that late last year on some 4" x 8" double-sided
phenolic substrate PCB stock after seeing all those "green"
site remarks that I didn't really believe. It WORKS! :-)
Those pieces had been sitting in the back of the workshop
for about 35 years.

I did "cheat" a bit. Have a year-round producing lemon
tree and my wife had some coarse salt left over from a
canning experiment. Zero cost trial...lemons at the
markets can run 50 cents each. The residue can easily
wash down the sink, don't need any gloves, nothing toxic.

Just make sure you don't get any of it in a cut on your finger. The
lemon will add a whole 'nother meaning to rubbing salt in your wounds!!

Result is easily solderable although for best appearance,
some cleaning with a bleach-containing kitchen cleanser
will make it shiny and spotless.

Or you can just bend all but the ground pins outward from the base of
the chip (e.g., www.speakeasy.net/
~jmiles1/ke5fx/492ap/large/close1.jpg). The pins won't break if you
don't flex them more than once or twice.

What's the board in? A receiver? What's it do?

It's a PLL that locks a Tek 492AP spectrum analyzer to an external 10
MHz GPS reference. The box contains an x100 prescaler, x10 prescaler, a
phase/frequency detector made from two halves of a 74LS74, and a slow
loop filter made from an LF356 opamp. There's also a relay that
switches the correction signal in and out of the circuit based on
whether the GPS reference is connected.

The 494 and 494A had the reflock assembly built in, but the 492A didn't.
So I added it, along with a few other tweaks that bring it up to 494A-
level functionality.

Lots of stuff in a very small box, without much room for component
standoffs or other prototyping aids. I've built a ton of stuff that
way, at frequencies up to and including 2 GHz. Wouldn't even consider
any other assembly techniques for RF work at this point.

-- jm

------------------------------------------------------
http://www.qsl.net/ke5fx
Note: My E-mail address has been altered to avoid spam
------------------------------------------------------

Hello Watson,

Why is that? Lead? I thought that paint with lead in it was a lot
worse.

I believe yes, plus other additives.

Regards, Joerg

http://www.analogconsultants.com

Hello Watson,

BTW, you can go to Michaels or other hobby/crafts store and buy a whole
handful of ice scream sticks for a couple bucks. You don't have to wash
'em, then. :-P

HD and Lowes have suitable hardwood strips, too. That is what I use when
it is a client's breadboard.

But these still don't come with vanilla almond chocolate crunch.
However, there is a trailer in front where they sell jumbo cajun links...

Regards, Joerg

http://www.analogconsultants.com

Hello Watson,

Back in the early '70s I got some prototype boards from a company that
made aircraft receivers. They used four push-in pins, one for each lead
of the four corners of the IC. Two of these are usually power and
ground, pins 7 or 8 and 14 or 16. These four hold the chip up off the
board, and the other pins are wired spaghetti style, which I presume is
the same as your sauerkraut style.

Neat. Yes, sauerkraut style is similar to spaghetti style. No meat sauce
though ;-)

Speaking of this.. Last Sunday at our monthly compouter club meeting
someone donated a homemade S-100 system to the consignment table, but no
one bought it, so it ended up on the freebies table later, probably then
into the trash later. It had a chassis and box pop riveted together,
and the S-100 bus was all wire wrapped. A lotta love and time went into
building that way back in the late '70s.

Oh, wire wrap. Most older computers were that way in the 70's when I was
at university. It caused a lot of grief but then I found out an upside.
As a student you are always short of money, looking for an opportunity
to make a buck. These old wire wrap graves still would have some life in
them but not enough for the institutes to warrant the huge service
contract expenses or $200/hour repairs. So they just sat there, dead.
Then I offered to repair them provided I could do it my way. Brought the
big solder iron and soldered the whole backplane which brought them back
to life. They actually ran more reliably then ever, some told me. Often
the pay wasn't money but a keg and pizza which was then immediately
consumed by me and some staff on the lawn in front of the place.

Regards, Joerg

http://www.analogconsultants.com

See if there is a PCB manufacturer within resonable driving distance and
ask for scraps. That's how I got a huge stash decades ago. Single and
double sided, the good stuff (FR4). But it has to be picked up, in my case
they wouldn't have gone through the trouble of packaging and mailing it.
Basically it had to be no more effort on their part than a walk to the
dumpster would have been.

Mine weren't tinned though. Also, I am not sure if constantly touching a
pre-tinned board during experiments would be too healthy.
===============================
Printed circuit board scraps up to large pieces ,be it usually double sided
, are always available at ham radio flea markets in the various european
countries. I think I have stocked up for life ! From the larger bits you
can make neat enclosures.

Frank GM0CSZ / KN6WH

"Watson A.Name - "Watt Sun, the Dark Remover"" wrote
in message ...

wrote in message
oups.com...
[snip]

Cleaning OLD PCB stock the "green" way -

Sprinkle any kind of table salt on the PCB stock, then take
half a lemon and rub it on the salt. Most of the blackened
oxide will disappear!

I've amazed a few people when we go out to eat lunch. I take a
tarnished golden dollar and put it in the lemon from a drink, or catsup
works just as well. Less than a minute later, it's nice and shiny
again. The vinegar or citric acid reduces all that tarnish to
invisible. Some say the carbonic acid in the fizz in cola will do it,
too, but I haven't tried it. Check it out sometime when you're into
impressing your friends.

I tried that late last year on some 4" x 8" double-sided
phenolic substrate PCB stock after seeing all those "green"
site remarks that I didn't really believe. It WORKS! :-)
Those pieces had been sitting in the back of the workshop
for about 35 years.

I did "cheat" a bit. Have a year-round producing lemon
tree and my wife had some coarse salt left over from a
canning experiment. Zero cost trial...lemons at the
markets can run 50 cents each. The residue can easily
wash down the sink, don't need any gloves, nothing toxic.

Just make sure you don't get any of it in a cut on your finger. The
lemon will add a whole 'nother meaning to rubbing salt in your wounds!!

Result is easily solderable although for best appearance,
some cleaning with a bleach-containing kitchen cleanser
will make it shiny and spotless.

"Pipex News Server" ) writes:
See if there is a PCB manufacturer within resonable driving distance and
ask for scraps. That's how I got a huge stash decades ago. Single and
double sided, the good stuff (FR4). But it has to be picked up, in my case
they wouldn't have gone through the trouble of packaging and mailing it.
Basically it had to be no more effort on their part than a walk to the
dumpster would have been.

Mine weren't tinned though. Also, I am not sure if constantly touching a
pre-tinned board during experiments would be too healthy.
===============================
Printed circuit board scraps up to large pieces ,be it usually double sided
, are always available at ham radio flea markets in the various european
countries. I think I have stocked up for life ! From the larger bits you
can make neat enclosures.

Frank GM0CSZ / KN6WH


Yes, I've been able to get it at the local "surplus" outlet for
thirty years, though I suppose at this point many a location no
longer has such a store.

They often have board that has been drilled, or shaped in a certain
design, clearly overrun or projects that got scrapped. If you
aren't actually etching the board, or if you only need small pieces,
these work fine and cost even less.

Because it's cheap, I've done things like use it for panels on projects.
Circuit board is a easier to work with than metal, yet the copper
provides shielding.

I've even pulled the copper off boards when I need it gone, though
that tends to be tedious. If it's just a small piece, I grind it
off.

Michael VE2BVW