I bought 3 old cell phones at a yard cell the other day to tinker
with. These are GPS equipped. I was wondering it would be possible to
take a signal off of these I could use as a time reference. At work we
have such a reference that supplies 10Mhz, 1Mhz 1 Hz and I think there
are other frequencies. I opened one up and dont have a clue to what
any of the chips do. Any help would be appreciated.

Jimmie

In
JIMMIE wrote:

I bought 3 old cell phones at a yard cell the other day to tinker
with. These are GPS equipped. I was wondering it would be possible to
take a signal off of these I could use as a time reference. At work we
have such a reference that supplies 10Mhz, 1Mhz 1 Hz and I think there
are other frequencies. I opened one up and dont have a clue to what
any of the chips do. Any help would be appreciated.

Rather than beating your head against a wall trying to figure that out, why
not look into a GPS module? You can get a Garmin GPS15 for less than $50.

https://buy.garmin.com/shop/shop.do?cID=157

I'm sure there are similar products from other makers.


--
Bert Hyman St. Paul, MN

Bert Hyman wrote:
In

JIMMIE wrote:

I bought 3 old cell phones at a yard cell the other day to tinker
with. These are GPS equipped. I was wondering it would be possible to
take a signal off of these I could use as a time reference. At work
we have such a reference that supplies 10Mhz, 1Mhz 1 Hz and I think
there are other frequencies. I opened one up and dont have a clue to
what any of the chips do. Any help would be appreciated.

Rather than beating your head against a wall trying to figure that
out, why not look into a GPS module? You can get a Garmin GPS15 for
less than $50.

https://buy.garmin.com/shop/shop.do?cID=157

I'm sure there are similar products from other makers.

Bert,
My take on your plan is that it's a losing battle. Cell phones are not
really designed with frequency standard capabilities in mind, and it's
rather far-fetched to think that you could easily find a 10.000000 MHz
frequency inside a cell phone. Even if you could find a stable reference
frequency inside a cell phone, you would likely need to build a good bit of
circuitry to get it back to 10 MHz.

I suggest that you search for Thunderbolt GPS on Ebay. Made by Trimble, the
units are GPS-based frequency standards that output 10 MHz and 1PPS signals.
They were built for the cellular industry, but unlike the cell phone, their
lot in life was to be a real frequency standard.
You can find them for approx. $100-$150 USD on Ebay. They are quite
reliable and are ready to run. You only need a GPS antenna and a PC with a
serial port to run them. After getting them set up with your PC, you can
disconnect the PC and it will run unattended. The software is free.
--
David
dgminala at mediacombb dot net

On May 10, 10:49*am, "Dave M" wrote:
Bert Hyman wrote:
In

JIMMIE wrote:

I bought 3 old cell phones at a yard cell the other day to tinker
with. These are GPS equipped. I was wondering it would be possible to
take a signal off of these I could use as a time reference. At work
we have such a reference that supplies 10Mhz, 1Mhz 1 Hz and I think
there are other frequencies. I opened one up and dont have a clue to
what any of the chips do. Any help would be appreciated.

Rather than beating your head against a wall trying to figure that
out, why not look into a GPS module? You can get a Garmin GPS15 for
less than $50.

https://buy.garmin.com/shop/shop.do?cID=157

I'm sure there are similar products from other makers.

Bert,
My take on your plan is that it's a losing battle. *Cell phones are not
really designed with frequency standard capabilities in mind, and it's
rather far-fetched to think that you could easily find a 10.000000 MHz
frequency inside a cell phone. *Even if you could find a stable reference
frequency inside a cell phone, you would likely need to build a good bit of
circuitry to get it back to 10 MHz.

I suggest that you search for Thunderbolt GPS on Ebay. *Made by Trimble, the
units are GPS-based frequency standards that output 10 MHz and 1PPS signals.
They were built for the cellular industry, but unlike the cell phone, their
lot in life was to be a real frequency standard.
You can find them for approx. $100-$150 USD on Ebay. *They are quite
reliable and are ready to run. *You only need a GPS antenna and a PC with a
serial port to run them. *After getting them set up with your PC, you can
disconnect the PC and it will run unattended. *The software is free.
--
David
dgminala at mediacombb dot net

I was hoping whether frequency standard or cell phone I was hoping
they all used the same chips. No such luck I guess.

Jimmie

On May 10, 5:22*pm, JIMMIE wrote:
On May 10, 10:49*am, "Dave M" wrote:





Bert Hyman wrote:
In

JIMMIE wrote:

I bought 3 old cell phones at a yard cell the other day to tinker
with. These are GPS equipped. I was wondering it would be possible to
take a signal off of these I could use as a time reference. At work
we have such a reference that supplies 10Mhz, 1Mhz 1 Hz and I think
there are other frequencies. I opened one up and dont have a clue to
what any of the chips do. Any help would be appreciated.

Rather than beating your head against a wall trying to figure that
out, why not look into a GPS module? You can get a Garmin GPS15 for
less than $50.

https://buy.garmin.com/shop/shop.do?cID=157

I'm sure there are similar products from other makers.

Bert,
My take on your plan is that it's a losing battle. *Cell phones are not
really designed with frequency standard capabilities in mind, and it's
rather far-fetched to think that you could easily find a 10.000000 MHz
frequency inside a cell phone. *Even if you could find a stable reference
frequency inside a cell phone, you would likely need to build a good bit of
circuitry to get it back to 10 MHz.

I suggest that you search for Thunderbolt GPS on Ebay. *Made by Trimble, the
units are GPS-based frequency standards that output 10 MHz and 1PPS signals.
They were built for the cellular industry, but unlike the cell phone, their
lot in life was to be a real frequency standard.
You can find them for approx. $100-$150 USD on Ebay. *They are quite
reliable and are ready to run. *You only need a GPS antenna and a PC with a
serial port to run them. *After getting them set up with your PC, you can
disconnect the PC and it will run unattended. *The software is free.
--
David
dgminala at mediacombb dot net

I was hoping whether frequency standard or cell phone I was hoping
they all used the same chips. No such luck I guess.

Jimmie- Hide quoted text -

- Show quoted text -

http://www.youtube.com/watch?v=0SOva4dqZbc

JIMMIE wrote:
I was hoping whether frequency standard or cell phone I was hoping
they all used the same chips. No such luck I guess.

Cell phones have a very high level of integration. In many
phones, there's one RF chip and one for everything else,
and in some, it's all on one chip. Basically there's nothing
except perhaps the display that you can hack.

On Tue, 11 May 2010, Clifford Heath wrote:

JIMMIE wrote:
I was hoping whether frequency standard or cell phone I was hoping
they all used the same chips. No such luck I guess.

Cell phones have a very high level of integration. In many
phones, there's one RF chip and one for everything else,
and in some, it's all on one chip. Basically there's nothing
except perhaps the display that you can hack.

That contrasts with the early ones, that were a great source of
parts. Even a decade ago, I was still finding the early cellphones,
in big clunky cases, and pretty much all the parts were recognizable
and thus reusable. NE560 compander ICs, 8bit CPUs that could be reused,
IF strips that were often on a small board that could be easily extracted.
TCXOs, crystal filters suitable for use as roofing filters, just lots
of good parts.

I'm not sure where the cutoff point was, but the smaller things got
the less they had parts that were recognizable. Any recent cellphone
has virtually no components, and none are really recognizable and
certainly aren't useful for other purposes.

Even cordless phones seem to have gone that way, a decade ago when
they were still down at the 49MHz range, there were plenty of good
parts, but when they migrated to higher frequencies they got more
integration and fewer useful parts.

Michael VE2BVW

On May 9, 8:50 pm, JIMMIE wrote:
I bought 3 old cell phones at a yard cell the other day to tinker
with. These are GPS equipped. I was wondering it would be possible to
take a signal off of these I could use as a time reference. At work we
have such a reference that supplies 10Mhz, 1Mhz 1 Hz and I think there
are other frequencies. I opened one up and dont have a clue to what
any of the chips do. Any help would be appreciated.

Jimmie10

hey OM:
There sure are alot of nay sayers here for sure.

Back in the day I used to repair TV's,.Now back then, in sum TV's they
took the NTSC color burst frequency off the IF via a filter, now true
it was a quartz crystal filter.
Wouldn't take much to use a pick up loop and a 10 MHz broadband filter
to pull off the frequency standard in a cell phone.

73 OM
n8zu