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Telephone parts?

I

Ivan Vegvary

One of the discounters in Portland is selling "slim-line" phones (land line, brand new) for $ 2.50 each.
Is this a bargain for parts? Anything fun and usable inside?
Thanks
Ivan Vegvary
 
J

Jasen Betts

One of the discounters in Portland is selling "slim-line" phones (land line, brand new) for $ 2.50 each.
Is this a bargain for parts? Anything fun and usable inside?

typical telephone parts include:
microphone, loudspeaker, ringer, DTMF circuit, keypad, cable, modular jack, case
 
P

passerby

responding to
http://www.electrondepot.com/electronics/telephone-parts-123871-.htm ,
passerby said:
ivanvegvary wrote:

"slim-line" phones for $ 2.50 each.
Is this a bargain for parts? Anything fun and usable inside?

A 3x4 keyboard, if you need one, may be worth more than that but the one in
the phone may be integrated into the PCB too much to be usable outside of the
phone's body and its PCB. The entire phone is pretty much on one big IC these
days so hard to tell if you can harvest many usable parts beyond the obvious
cables and perhaps that keyboard. Do you need an electret mic? There's one in
there as well as a (really bad quality) loudspeaker. There's probably a reed
switch in there.

It's been more than 10 years since I've been inside an analog land line
telephone set but I think it's safe to assume that the never ending
miniaturization made the amount of re-usable parts in those phones pretty
minimal by now.
--
 
M

Michael Black

One of the discounters in Portland is selling "slim-line" phones (land
line, brand new) for $ 2.50 each. Is this a bargain for parts?
Anything fun and usable inside? Thanks Ivan Vegvary
The likely value of the parts goes up if you actually have need of
something phone related. So if you needed a touchtone pad, you might be
able to get that function out of it (once upon a time, that sort of thing
was common, by now with most phones doing touchtone, there's a lot less
need). It won't even be good as an interface to the phone line, since it
likely has no isolation (counting on the circuit being used without
external conenctions and just as the IC manufacturer lays out the cicuit).

SOmething current is a lot less likely to be useful, as others have
pointed out, because the integration is high.

If you're buying new things, then something like those 99cent FM radios
would have a descendent of the TDA7000 FM receiver IC that had some use if
you were building FM receivers. I've yet to see them, but legend has it
that some low end AM radios use a descendent of the ZN414 TRF AM receiver
IC that used to see a lot of projects. That sort of thing doesn't offer
much by building it yourself, but it's a cheap and handy way to get the
ICs.

If you're just looking for parts, go to garage and rummage sales, and buy
used electronics that nobody wants and is thus cheap. Older cordless
phones offer up way more parts than some cheap solid state phone,
especially if you're interested in radio. VCRs will offer motors and
endless small signal transistors and if it's old enough, transformers with
multiple windings. Satellite boxes are common, the parts are limited but
if the price is right. They often provide a nice cabinet. Anything
that's cheap (and the older the better because it won't be so highly
integrated) is likely to be better than buying something cheap and new off
the shelf.

Or look for these things in the garbage. I brought home another cassette
deck last week, I don't think it's any better than what I've found in the
garbage before, so I'll likely strip it. It will offer up a power
transformer (something that often costs real money when building
something), some DC motors, endless small signal transistors, and if
noth8ing else, an LED VU meter. I once needed an ac adapter for a
Powerbook 1400C I got at a rumamge sale, and remembering for some reason
that inkjet printers tend to have higher voltage supplies (I needed
24vdc), I opened one I'd brought home, and extracted a nice module to
provide the needed power. Inkjets are also common, lots of mechanical
parts (though not as many as dot-matrix printers) and likely enough parts
if they are found in the garbage (and thus free) though with an IC
controller they tend to be a tad too specific. They tend to have some
power transistors.

That's the thing, some items are better than others for certain parts.

Michael
 
B

BeeJ

Ivan Vegvary was thinking very hard :
One of the discounters in Portland is selling "slim-line" phones (land line,
brand new) for $ 2.50 each. Is this a bargain for parts? Anything fun and
usable inside? Thanks
Ivan Vegvary

Plug it in and use it. Emergency use when cell towers go down or power
goes out.
Send me a couple.

I just bought a Panasonic DECT wireless phone with a standard phone
base station so I have phone access when the power goes out.
 
I

Ivan Vegvary

One of the discounters in Portland is selling "slim-line" phones (land line, brand new) for $ 2.50 each.

Is this a bargain for parts? Anything fun and usable inside?

Thanks

Ivan Vegvary

Thanks everyone for the great insight. I guess I'll be buying one of these phones just to see what's inside. All the comments about integration are excellent points that I had not considered.

Ivan Vegvary
 
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