I have a precor EFX 546 http://www.precor.com/cpr_efx_546.php . I
would like to mount a monitor and PC to it. This I can do no problem.

Where the tricky part comes in is. I would like to hook the PC up to
the Precor, so if I stop exercising the pc hibernates or something
along those lines. My ultimate goal is to tie the speed of pedaling to
curtain key strokes. I am pretty machanically inclined, just not sure
where to start.

I find myself playing online games about 4 hours a week. If I spent
those four hour on my lovely Precor, those last ten pounds everyone
talks about would be sure to come off.

---

Request for Question Clarification by aht-ga on 18 Dec 2003 11:51 PST

afreestyle-ga:

There do not seem to be any ready-made accessories that can solve this
problem for you, but there are definitely possible solutions depending
on how much work you are willing to do, and whether a violation of the
manufacturer's warranty would be a problem for you. As long as you are
the only person using this exercise machine, the only real issue
behind violating the warranty is whether or not you can get the
machine repaired should it fail. As for the amount of work, it depends
on how much experience you have in working with electronics, switches,
and circuitry. Depending on the final solution, it may also require
some custom programming. Are you willing to invest the time and effort
to make this automated exercise buddy a reality, or do you think that
you have the discipline to just use the elliptical trainer and the PC
at the same time without requiring them to be linked?

Regards,

aht-ga
Google Answers Researcher

---

Clarification of Question by afreestyle-ga on 18 Dec 2003 13:28 PST

The Precor is in my garage and is otherwise out of warrenty. I am also
good friends with the Fitness Warehouse manager, were I purchased it.
So that said. I am just looking for some extra motivation to get on
the thing and also kill two bird with one stone.

Just hooking up the PC is no fun. I want that fear or thought in my
head that if I do not keep up the pace I will be kicked off. Plus I
love learning new things.

I can do it, if just pointed in the right direction. My Dad has been
in the electrical feld for 30 years, so I am sure I could get help
from him. I ran this by him and he felt it could be done but wasn't
sure were to start.

My thought was to somehow translating the speed sensor on the Precor.
Maybe to a small bread board connected to a serial cable. Then run a
small program on Windows to cuase hibernation or network disconect,
when speed gets to low or stops. Or like I said earlier to just
trigger certian keys on the keyboard.

---

Request for Question Clarification by aht-ga on 18 Dec 2003 15:32 PST

There are several options to 'hack' this solution together. Not having
access to an EFX 546 myself to investigate further with, all I can do
is point you in the right direction.

First, National Gym Supply ( http://www.gympart.com ) advertises that
they have complete electronics repair services for the EFX 546. I
mention this in case you end up needing to buy replacement parts.

The simplest way to link use of the elliptical trainer with the status
of the PC, would be the "brute force" method:

1. Buy an uninterruptible power supply sized to give your system at
least 10 minutes of run time (including monitor), with either USB or
serial monitoring for the PC and Windows Advanced Power Management

2. Buy a power relay rated to handle the maximum in-rush and constant
current required by the UPS (120VAC side), said relay being controlled
by a 12VDC signal

3. With a bit of ingenuity, open up the EFX 546, locate the generator
circuit/assembly that allows the unit to self-power while in use,
locate the regulated low voltage side of that circuit, and tap into it
to power the relay signal.

4. In Windows Power Management, set the first alarm threshold to 90%,
along with a sound warning and a pop-up warning.

5. Set the second alarm threshold to 65 or 70%, with the action being Hibernate.

What this should give you, is a system where, when you are pumping
away on the EFX 546, the relay will allow 120VAC power to flow to the
UPS, and you can start up the computer. As long as you are pumping
away, there will be power applied to the signal side of the power
relay, keeping the 120VAC flowing to the UPS. If you stop pumping, the
generator circuit will eventually cut out, power to the relay is cut,
the relay opens, and the UPS kicks in (usually with an audible
warning). The PC receives the warning over either the USB or serial
connection to the UPS, and begins monitoring the battery power level
remaining in the UPS. It'll pop up the first alarm warning, then when
the power drops to the second alarm level, it will initiate
hibernation. Note that, at this point, the only way to continue is to
start pumping away again, and bring the computer back out of
hibernation.

For those times when you actually want to use the PC without the
elliptical, you can install a two-way switch with the power relay to
allow you to bypass the relay.

Tapping into the speed sensor will be a lot more difficult an
approach; chances are the sensor is simply an encoder wheel or a
magnetic pickup. If it's an encoder wheel, you cannot easily tap into
its output without potentially affecting the actual speed measurement
capabilities of the unit's onboard 'computer'. Same goes for the
magnetic pickup, as in both cases the speed will be measured based on
the number of electrical pulses per second are transmitted. While it
may be possible to carefully tap into the output, and feed it into a
programmable controller like a PIC chip, it's a lot of trouble and
will require a lot of trial and error. If you choose to go this way,
though, then you'll need to get a PIC chip programmer, some manuals, a
logic scope... lots of equipment, actually.

I've posted this as a Clarification, primarily because I'm not sure if
this is the sort of Answer you are looking for. If it is, and if you
think that this information (and optionally further clarification) is
worth the price you've listed, then please let me know and I will post
this as the Answer, and provide any further clarification you seek.

Regards,

aht-ga
Google Answers Researcher

---

Clarification of Question by afreestyle-ga on 19 Dec 2003 09:48 PST

I know were to get a UPS and what type.

If you could get more info on were to pickup the power relay and the
two-way switch, that would be great. I live in the San Diego CA area.
Also a link or two to the PIC-chip stuff, just to read about, it
sounds interesting.

Other then that I would consider my question answered. Thanks for the
great UPS idea that was something that never crossed my mind.

afreestyle-ga:

Thank you for your Question. As requested, here is the Answer based on my 

original Question Clarification post.

---------------------------------

There are several options to 'hack' this solution together. Not having
access to an EFX 546 myself to investigate further with, all I can do
is point you in the right direction.

First, National Gym Supply ( http://www.gympart.com ) advertises that
they have complete electronics repair services for the EFX 546. I
mention this in case you end up needing to buy replacement parts.

The simplest way to link use of the elliptical trainer with the status
of the PC, would be the "brute force" method:

1. Buy an uninterruptible power supply sized to give your system at
least 10 minutes of run time (including monitor), with either USB or
serial monitoring for the PC and Windows Advanced Power Management

2. Buy a power relay rated to handle the maximum in-rush and constant
current required by the UPS (120VAC side), said relay being controlled
by a 12VDC signal

3. With a bit of ingenuity, open up the EFX 546, locate the generator
circuit/assembly that allows the unit to self-power while in use,
locate the regulated low voltage side of that circuit, and tap into it
to power the relay signal.

4. In Windows Power Management, set the first alarm threshold to 90%,
along with a sound warning and a pop-up warning.

5. Set the second alarm threshold to 65 or 70%, with the action being Hibernate.

What this should give you, is a system where, when you are pumping
away on the EFX 546, the relay will allow 120VAC power to flow to the
UPS, and you can start up the computer. As long as you are pumping
away, there will be power applied to the signal side of the power
relay, keeping the 120VAC flowing to the UPS. If you stop pumping, the
generator circuit will eventually cut out, power to the relay is cut,
the relay opens, and the UPS kicks in (usually with an audible
warning). The PC receives the warning over either the USB or serial
connection to the UPS, and begins monitoring the battery power level
remaining in the UPS. It'll pop up the first alarm warning, then when
the power drops to the second alarm level, it will initiate
hibernation. Note that, at this point, the only way to continue is to
start pumping away again, and bring the computer back out of
hibernation.

For those times when you actually want to use the PC without the
elliptical, you can install a two-way switch with the power relay to
allow you to bypass the relay.

Tapping into the speed sensor will be a lot more difficult an
approach; chances are the sensor is simply an encoder wheel or a
magnetic pickup. If it's an encoder wheel, you cannot easily tap into
its output without potentially affecting the actual speed measurement
capabilities of the unit's onboard 'computer'. Same goes for the
magnetic pickup, as in both cases the speed will be measured based on
the number of electrical pulses per second are transmitted. While it
may be possible to carefully tap into the output, and feed it into a
programmable controller like a PIC chip, it's a lot of trouble and
will require a lot of trial and error. If you choose to go this way,
though, then you'll need to get a PIC chip programmer, some manuals, a
logic scope... lots of equipment, actually.

-----------------------------------

In addition to this, you wanted some guidance about where to source the two-way 

switch and the power relay. You also wanted some references to PIC chips and 

programming.

For the two-way switch and power relay, your best bet is your local electrical 

supply store. You mentioned that your father is in the electrical field, so 

chances are he is the best person to tell you where the nearest electrical supply 

store is. Such stores carry parts and supplies for electricians and mechanics. 

The parts you are looking for are similar to the following:

1) Double Pole, Double Throw (Center-OFF) Switch (125VAC 15A minimum)

http://www.mcgillelectrical.com/specToggle_multi.htm

Any electrical supply store should be able to sell you something that meets this 

requirement. Again, the important thing is that it is a double-pole, double-throw 

(center-OFF) switch rated for at least 125VAC 15A duty.


2) Single Pole, Double Throw General Purpose Relay (12VDC control, 15A minimum 

for output contacts)

http://oeiwcs.omron.com/webapp/commerce/command/ExecMacro/Omron/macros/itemdisp.d

2w/report?prmenbr=316&prrfnbr=3264

Now, note that I am pointing you to a 12 VDC coil relay. I do not know what the 

generator in the elliptical trainer actually generates (in voltage). You are best 

advised to open up the trainer first, figure out where to tap into the DC output 

of the generator assembly, then find an appropriate relay. If the generator is 

using something other than 12 or 24 VDC as it's output, then the relay will be 

more difficult to obtain from an electrical supply store. However, they should be 

able to point you to someone else in the local area who carries parts for 

electronic hobbyists, if you need something with a 3V, 6V, or 9V coil. The 

challenge will be that these tend to be meant for use on a circuit board, and 

will require some additional work to integrate into this control circuit.

----------------------------------

Information about PIC chips, and programming PIC chips, can best be found at the 

manufacturer's website. Microchip manufactures the PIC chip, and has a faithful 

following among electronic hobbyists, engineering students, and the folks who 

like to hack into Playstations and other gaming consoles. The PIC chip is an 

extremely versatile, extremely basic programmable controller. If you have any 

interest at all in taking up electronics as a hobby, the PIC chip is a good place 

to start.

Microchip Website:

http://www.microchip.com/1010/index.htm

An Excellent article:

http://www.seattlerobotics.org/encoder/may97/picchip.html

Some Fan sites:

http://www.topology.org/hard/pic.html

Programmer retailer:

http://www.didya.com/ChipProgrammers.htm

----------------------------------


I hope you found this information useful, and good luck with this project!

Regards,

aht-ga
Google Answers Researcher