[sci.electronics] Radio Shack parts, quality of

jbn@glacier.STANFORD.EDU (John B. Nagle) (06/16/88)

     With the decline of northern Silicon Valley as a R&D area in electronics,
it has become more difficult to buy electronic parts in the area.  Within
the past few months, the local branches of Zack's and Dick Smith have
closed.  Hamilton/Avnet moved out a few years back.  We have a surfeit of
yuppie-based businesses; there are at least two major design firms,
three desktop publishing shops, and four computer stores in downtown
Palo Alto.  (The high-end audio store and the BMW dealership are a bit
further away, and the fashion mall with the Neiman-Marcus and the Bullocks
is a few blocks away on the Stanford campus.)  While mail order is useful, 
occasionally one needs to run out and buy some wire, or a power supply.  
One would think that Radio Shack could meet these needs.  One would be wrong.

     I recently purchased some 12v 500ma DC power supplies, of the wall-
transformer type, from Radio Shack.  I discovered, though, that while the
supplies could deliver 12v, or 500ma, obtaining both at the same time was
too much to ask.  Output voltage dropped to 10.5v at 250ma.  This seemed
rather tacky, even for Radio Shack.

     So, while taking these back, I decided to purchase some wire,
ordinary 20ga stranded wire, three different colors in one blister pack,
and so marked.  What could go wrong?  Two spools held stranded wire.  One 
held solid 20ga wire.

     So, if anyone out there works for an electronic parts retailer
interested in locating in a new area, consider Palo Alto, Redwood City, 
or Mountain View.  There is no competition.  
     
					John Nagle

     
      

larry@kitty.UUCP (Larry Lippman) (06/18/88)

In article <17492@glacier.STANFORD.EDU>, jbn@glacier.STANFORD.EDU (John B. Nagle) writes:
>      I recently purchased some 12v 500ma DC power supplies, of the wall-
> transformer type, from Radio Shack.  I discovered, though, that while the
> supplies could deliver 12v, or 500ma, obtaining both at the same time was
> too much to ask.  Output voltage dropped to 10.5v at 250ma.  This seemed
> rather tacky, even for Radio Shack.

	You have to learn how to interpret Radio Shack specifications.  In
the case of power supplies, just think of EITHER/OR, as in auto warranties.
The transformer is obviously rated at 12 volts or 500 mA, whichever comes
first.

	:-)

<>  Larry Lippman @ Recognition Research Corp., Clarence, New York
<>  UUCP:  {allegra|ames|boulder|decvax|rutgers|watmath}!sunybcs!kitty!larry
<>  VOICE: 716/688-1231        {hplabs|ihnp4|mtune|utzoo|uunet}!/
<>  FAX:   716/741-9635 {G1,G2,G3 modes}   "Have you hugged your cat today?" 

matthew@ucscb.UCSC.EDU (73550000) (06/18/88)

In article <17492@glacier.STANFORD.EDU> jbn@glacier.STANFORD.EDU (John B. Nagle) writes:
>
>     With the decline of northern Silicon Valley as a R&D area in electronics,
>it has become more difficult to buy electronic parts in the area.  ...
> [much deleted]
>
>     So, if anyone out there works for an electronic parts retailer
>interested in locating in a new area, consider Palo Alto, Redwood City, 
>or Mountain View.  There is no competition.  
>     
>					John Nagle
>
except Fry's Electronics in Sunnyvale/Santa Clara (just
a short hop down 101 from Palo Alto/Mountain View)
If you haven't been there, you MUST go, just to see what happens
when you combine a components retail shop and a grocery store.
Really.

Matthew Kaufman
matthew@ucscb.ucsc.edu
...!ucbvax!ucscc!ucscb!matthew
.

phd@speech1.cs.cmu.edu (Paul Dietz) (06/18/88)

In article <17492@glacier.STANFORD.EDU> jbn@glacier.STANFORD.EDU (John B. Nagle) writes:
>     So, if anyone out there works for an electronic parts retailer
>interested in locating in a new area, consider Palo Alto, Redwood City, 
>or Mountain View.  There is no competition.  

No competition?! Try Pittsburgh! You'll be competing with TV repair
shops that only sell those "hard to find tubes." Of course, there aren't
any customers to speak of (except me!) ...

Paul H. Dietz                                        ____          ____
Dept. of Electrical and Computer Engineering        / oo \        <_<\\\
Carnegie Mellon University                        /|  \/  |\        \\ \\
--------------------------------------------     | | (  ) | |       | ||\\
"If God had meant for penguins to fly,             -->--<--        / / |\\\  /
he would have given them wings."            _________^__^_________/ / / \\\\-

jbn@glacier.STANFORD.EDU (John B. Nagle) (06/19/88)

     The Radio Shack 273-1653 supply (12v, 1a) produces about .2v of
ripple when delivering 250ma into a resistive load.  This increases to
.3v at 500ma.  The output voltage also drops.  

     I had just assumed that these little supplies had 7812s in them.
No.  Fortunately, Stancor has some real wall-transformer type power supplies.

					John Nagle

rkarlqu@hpscdc.HP.COM (Rick Karlquist) (06/21/88)

>     I recently purchased some 12v 500ma DC power supplies, of the wall-
>transformer type, from Radio Shack.  I discovered, though, that while the
>supplies could deliver 12v, or 500ma, obtaining both at the same time was
>too much to ask.  Output voltage dropped to 10.5v at 250ma.  This seemed
>rather tacky, even for Radio Shack.

>     So, while taking these back, I decided to purchase some wire,
>ordinary 20ga stranded wire, three different colors in one blister pack,
>and so marked.  What could go wrong?  Two spools held stranded wire.  One 
>held solid 20ga wire.

Halted Specialties in Sunnyvale always has lots of wall transformers
at reasonable prices.  They have a test bench at the store where you 
can characterize them before buying.  They also sell 1000 foot spools
of hook up wire.  While you're in the neighborhood, you can also
go to Fry's electronics, up Lawrence expressway about a mile.

rona@videovax.Tek.COM (Ronald K. Anderson) (06/22/88)

I'll never forget the first time I designed and built a circuit using
transistors ( a pack of 2N2222A's purchased from RS). I had never examined
a working transistor to that point, so it took a little longer to discover 
that their parts were the culprit. Replacing them with equivalents from an 
electronic junk store fixed my circuit and forever biased my skepticism of 
that outfit. If it wasn't the first time, and if I wasn't trying to learn
something, I don't think it would have bothered me so much.

I still buy stuff from them, but usually when I have no other alternative.

keithl@vice.TEK.COM (Keith Lofstrom) (06/22/88)

This is probably out of line, but:

We had a marketing manager who told us we could sell our rejects to Radio
Shack (he did at his previous job).   We fired the son-of-a-bitch.  He told
us a story about the kits that "a certain nationally-known consumer electronics
retailer" sells:

------ The following story is second hand.  Don't sue me, please --------

The kits are put together out of rejects.  Half the kits stay on the shelves
at the store and never sell.  The ones that do are bought as educational gifts
for teenagers.  90 percent of the teenagers never open the kits, and throw
them away.  90 percent of those that open the kits can't manage to put them
together, and throw them away.  Of the one percent that do complete the kits
- which probably don't work - 90 percent assume that they didn't do it right,
and throw them away.  

The last 0.1% take the kits back to the store and ask for working parts.
So, the company ships a complete new kit (with working parts) for every 
one in 2000 kits they make.  It's cheaper that way.

Just think, if you had gotten your kits elsewhere, you'd now be an EE
instead of a CS person...

------------------------------------------------------------------------------
I'd better put a disclaimer on this.  None of my managers want me to write bad
things about big companies that buy equipment and employ lawyers, so I wrote
this without approval.  As a matter of fact, this is actually being written by
a 14 year old kid who broke into my account.  Yah, that's the ticket!
------------------------------------------------------------------------------

-- 
Keith Lofstrom   ...!tektronix!vice!keithl   keithl@vice.TEK.COM
MS 59-316, Tektronix, PO 500, Beaverton OR 97077  (503)-627-4052

aboulang@bbn.com (Albert Boulanger) (06/25/88)

  Halted Specialties in Sunnyvale always has lots of wall transformers
  at reasonable prices.  They have a test bench at the store where you 
  can characterize them before buying.  They also sell 1000 foot spools
  of hook up wire.  While you're in the neighborhood, you can also
  go to Fry's electronics, up Lawrence expressway about a mile.


Or ACE Electronics just down the block! Or Haltek Electronics.... God,
I wish we New Englander's had as many surplus places as you all in
Silicon Valley. Now, who was complaining about no being able to find electronic
part stores around Redwood city?

If you can, get a copy of Nuts and Volts magazine

Albert Boulanger
aboulanger@bbn.com
Albert Boulanger
BBN Labs Inc.
ABoulanger@bbn.com (arpa)
Phone: (617)873-3891