Do you think splicing 100' of wire onto a GTO exit wand woul

[Elmo]

I bought too short of a driveway-gate exit wand (GTO FM139 = 50 feet); I
need 150 feet.

Nobody told me (so I'm saying it here), one really needs about 150 feet if
they want the driveway gate to be open by the time the moving mass of metal
(i.e., automobile) reaches the gate. Lesson learned.

Researching the web, it appears GTO sells three wands:
http://www.gtopro.com/access_controls.htm
- FM139 = 50 feet wired (about $180)
- FM140 = 100 feet wired (about $200)
- FM141 = 150 feet wired (about $225)

The instructions say you can not splice additional lengths
(http://www.gtopro.com/PDF/Flyers/Gate-Opener-Access-Control-FM139-vehicle-sensor.pdf
)

Calling www.gtopro.com technical support at 800-543-4283, they say there is
no difference between the wands or the wire other than the length BUT if I
splice in a wire, it won't work.

The technical support guy was very helpful. He said the reason it won't
work is that the "sensitivity of the magnetic field" changes with the
splice.

I don't understand why (if I make a good splice) but maybe there is
something about magnetic fields I don't understand that you can elucidate
for me? The wire is 5 conductor 16awg multi-strand shielded.

What is it about a splice that destroys the magnetic field?

 

[Bill]

One thing is shielding of the splice...
http://en.wikipedia.org/wiki/Faraday_cage

Then other than that, the wire length might have a certain *total*
resistance or *total* capacitance and this is adjusted for at the wand or at
the adjustment for the wand.

This principal might be along the lines of adjusting a CB antenna like it
says here (length of the antenna matters)...
http://www.wearecb.com/support/setcbantenna.htm




"Elmo" wrote in message

I bought too short of a driveway-gate exit wand (GTO FM139 = 50 feet); I
need 150 feet.

Nobody told me (so I'm saying it here), one really needs about 150 feet if
they want the driveway gate to be open by the time the moving mass of
metal
(i.e., automobile) reaches the gate. Lesson learned.

Researching the web, it appears GTO sells three wands:
http://www.gtopro.com/access_controls.htm
- FM139 = 50 feet wired (about $180)
- FM140 = 100 feet wired (about $200)
- FM141 = 150 feet wired (about $225)

The instructions say you can not splice additional lengths
(http://www.gtopro.com/PDF/Flyers/Gate-Opener-Access-Control-FM139-vehicle-sensor.pdf
)

Calling www.gtopro.com technical support at 800-543-4283, they say there
is
no difference between the wands or the wire other than the length BUT if I
splice in a wire, it won't work.

The technical support guy was very helpful. He said the reason it won't
work is that the "sensitivity of the magnetic field" changes with the
splice.

I don't understand why (if I make a good splice) but maybe there is
something about magnetic fields I don't understand that you can elucidate
for me? The wire is 5 conductor 16awg multi-strand shielded.

What is it about a splice that destroys the magnetic field?

 

[William Sommerwerck]

The technical support guy was very helpful. He said the
reason it won't work is that the "sensitivity of the magnetic
field" changes with the splice.

On the face of it, this is a pile of manure.

It's possible (as someone else said) that the system might be calibrated for
specific cable lengths, and it might be difficult to splice the wire in such
a way as to maintain the desired electrical characteristics. But an amateur
antenna system has at least two "splices" in it -- one at the transmitter,
the other at the antenna -- and it works fine.

If the folks running the company are "nice" people, they should take back
the too-short cable -- even though it's been used -- and give you full
credit towards a cable of the right length.

 

[GregS]

In article <ce74f791840c3849697fd11b070dd0af@tioat.net>, Elmo <dcdraftworks@Use-Author-Supplied-Address.invalid> wrote:

I bought too short of a driveway-gate exit wand (GTO FM139 = 50 feet); I
need 150 feet.

Nobody told me (so I'm saying it here), one really needs about 150 feet if
they want the driveway gate to be open by the time the moving mass of metal
(i.e., automobile) reaches the gate. Lesson learned.

Researching the web, it appears GTO sells three wands:
http://www.gtopro.com/access_controls.htm
- FM139 = 50 feet wired (about $180)
- FM140 = 100 feet wired (about $200)
- FM141 = 150 feet wired (about $225)

The instructions say you can not splice additional lengths
(http://www.gtopro.com/PDF/Flyers/Gate-Opener-Access-Control-FM139-vehicle-sens
or.pdf
)

Calling www.gtopro.com technical support at 800-543-4283, they say there is
no difference between the wands or the wire other than the length BUT if I
splice in a wire, it won't work.

The technical support guy was very helpful. He said the reason it won't
work is that the "sensitivity of the magnetic field" changes with the
splice.

I don't understand why (if I make a good splice) but maybe there is
something about magnetic fields I don't understand that you can elucidate
for me? The wire is 5 conductor 16awg multi-strand shielded.

What is it about a splice that destroys the magnetic field?

First thing, how do you get IN ????

Second thing, try an additional 5-10 feet and see if there
is something other than ??

Whats the connector look like ??

greg

 

[George]

On 2/1/2010 12:53 PM, GregS wrote:

In article<ce74f791840c3849697fd11b070dd0af@tioat.net>, Elmo<dcdraftworks@Use-Author-Supplied-Address.invalid> wrote:
I bought too short of a driveway-gate exit wand (GTO FM139 = 50 feet); I
need 150 feet.

Nobody told me (so I'm saying it here), one really needs about 150 feet if
they want the driveway gate to be open by the time the moving mass of metal
(i.e., automobile) reaches the gate. Lesson learned.

Researching the web, it appears GTO sells three wands:
http://www.gtopro.com/access_controls.htm
- FM139 = 50 feet wired (about $180)
- FM140 = 100 feet wired (about $200)
- FM141 = 150 feet wired (about $225)

The instructions say you can not splice additional lengths
(http://www.gtopro.com/PDF/Flyers/Gate-Opener-Access-Control-FM139-vehicle-sens
or.pdf
)

Calling www.gtopro.com technical support at 800-543-4283, they say there is
no difference between the wands or the wire other than the length BUT if I
splice in a wire, it won't work.

The technical support guy was very helpful. He said the reason it won't
work is that the "sensitivity of the magnetic field" changes with the
splice.

I don't understand why (if I make a good splice) but maybe there is
something about magnetic fields I don't understand that you can elucidate
for me? The wire is 5 conductor 16awg multi-strand shielded.

What is it about a splice that destroys the magnetic field?


First thing, how do you get IN ????

They didn't say they couldn't get any but that the gate didn't open fast
enough for the speed they were driving. Obviously one solution might be
to go a little slower.

Second thing, try an additional 5-10 feet and see if there
is something other than ??

Whats the connector look like ??

greg

 

[DerbyDad03]

On Feb 1, 10:15 am, Elmo <dcdraftwo...@Use-Author-Supplied-
Address.invalid> wrote:

I bought too short of a driveway-gate exit wand (GTO FM139 = 50 feet); I
need 150 feet.

Nobody told me (so I'm saying it here), one really needs about 150 feet if
they want the driveway gate to be open by the time the moving mass of metal
(i.e., automobile) reaches the gate. Lesson learned.

Researching the web, it appears GTO sells three wands:http://www.gtopro.com/access_controls.htm
- FM139 = 50 feet wired (about $180)
- FM140 = 100 feet wired (about $200)
- FM141 = 150 feet wired (about $225)

The instructions say you can not splice additional lengths
(http://www.gtopro.com/PDF/Flyers/Gate-Opener-Access-Control-FM139-veh...
)

Callingwww.gtopro.comtechnical support at 800-543-4283, they say there is
no difference between the wands or the wire other than the length BUT if I
splice in a wire, it won't work.

The technical support guy was very helpful. He said the reason it won't
work is that the "sensitivity of the magnetic field" changes with the
splice.

I don't understand why (if I make a good splice) but maybe there is
something about magnetic fields I don't understand that you can elucidate
for me? The wire is 5 conductor 16awg multi-strand shielded.

What is it about a splice that destroys the magnetic field?

Add the required number/severity of speed bumps to force the drivers
to slow down to whatever speed works for the 50 foot wand.

 

[GregS]

In article <hk76tf$7o5$1@news.eternal-september.org>, George <george@nospam.invalid> wrote:

On 2/1/2010 12:53 PM, GregS wrote:
In article<ce74f791840c3849697fd11b070dd0af@tioat.net>,
Elmo<dcdraftworks@Use-Author-Supplied-Address.invalid> wrote:
I bought too short of a driveway-gate exit wand (GTO FM139 = 50 feet); I
need 150 feet.

Nobody told me (so I'm saying it here), one really needs about 150 feet if
they want the driveway gate to be open by the time the moving mass of metal
(i.e., automobile) reaches the gate. Lesson learned.

Researching the web, it appears GTO sells three wands:
http://www.gtopro.com/access_controls.htm
- FM139 = 50 feet wired (about $180)
- FM140 = 100 feet wired (about $200)
- FM141 = 150 feet wired (about $225)

The instructions say you can not splice additional lengths

(http://www.gtopro.com/PDF/Flyers/Gate-Opener-Access-Control-FM139-vehicle-sen
s
or.pdf
)

Calling www.gtopro.com technical support at 800-543-4283, they say there is
no difference between the wands or the wire other than the length BUT if I
splice in a wire, it won't work.

The technical support guy was very helpful. He said the reason it won't
work is that the "sensitivity of the magnetic field" changes with the
splice.

I don't understand why (if I make a good splice) but maybe there is
something about magnetic fields I don't understand that you can elucidate
for me? The wire is 5 conductor 16awg multi-strand shielded.

What is it about a splice that destroys the magnetic field?


First thing, how do you get IN ????

They didn't say they couldn't get any but that the gate didn't open fast
enough for the speed they were driving. Obviously one solution might be
to go a little slower.

This is for exit only. I asked how do they get in, thinking any decent gate
will have a remote control. Go through same procedure as to get
in, push button. !!!! That RF is a usefull thing !!! Remote control !!!
A magnetic sensor is usefull to prevent closing the gate and hitting car.


greg

Second thing, try an additional 5-10 feet and see if there
is something other than ??

Whats the connector look like ??

greg

 

[mm]

On Mon, 1 Feb 2010 15:15:51 +0000 (UTC), Elmo
<dcdraftworks@Use-Author-Supplied-Address.invalid> wrote:

What is it about a splice that destroys the magnetic field?

I know that when my girlfriend got spliced, it destroyed our magnetic
field.

Seriously, I'm a 3 or 4 out of 10 on electronics knowledge, not even a
skilled amateur, but this reminds me of "No user-serviceable parts
inside". It depends on who the user is. I even saw that on a Black &
Decker tire pump, on the plug for the cigarette lighter. I drilled
out the rivets, replaced a burned-out fuse, and it's worked fine for
10 years now.

The product you write about seems intended for corporations and rich
people. I'll bet it's a way to squeeze another 150 dollars out of
you.

(They won't exchange what you bought for the longer one because you
buried yours already and it's dirty?)

Oh, yeah, the technician might even believe what he told you even if
I'm right.

It would be easier to do a nice splice if you offset the individual
splices an inch or so from each other.

To the other people here, any reason he can't use one sheet of
alimumim foil to shield everything all at once.

If you're burying it when you're done, silicone tape, I think it's
called, is even better than heat-shrink tubing and doesn't slip on, it
wraps on. Stretch it to 2 or 3 times its length, then wrap while
streched and within a few days it merges into one big probably
waterproof blob. Hard to find though.

 

On Mon, 01 Feb 2010 19:47:16 GMT, zekfrivo@zekfrivolous.com (GregS)
wrote:

In article <hk76tf$7o5$1@news.eternal-september.org>, George <george@nospam.invalid> wrote:


This is for exit only. I asked how do they get in, thinking any decent gate
will have a remote control. Go through same procedure as to get
in, push button. !!!! That RF is a usefull thing !!! Remote control !!!
A magnetic sensor is usefull to prevent closing the gate and hitting car.


greg

Could be like the gate at a corporate site I occasionally visit - for
entry, you speak to a guard and show ID via a TV camera and the guard
opens the gate. A device like the one in this thread is used to allow
people to exit the gate.

John

 

[Elmo]

On Mon, 01 Feb 2010 17:53:54 GMT, GregS wrote:

First thing, how do you get IN ????
Whats the connector look like ??

There is a keypad to get in, and a remote.
Both work fine for the owner of the house, but not for guests.
Guests enter via the outside-the-gate intercom keypad.
But the gate closes 25 seconds after being opened.
When guests leave, the exit wand triggers the gate to open.

 

[Elmo]

On Mon, 01 Feb 2010 17:53:54 GMT, GregS wrote:

Whats the connector look like ??

There is no connector. Each of the four 16 AWG multi-stranded wires arrives
from the factory stripped of about 1/4 inch at the ends and tinned solid.

We just screw those four wires plus the shield into connections on the gate
opener motherboard.

 

[Elmo]

On Mon, 01 Feb 2010 19:47:16 GMT, GregS wrote:

That RF is a usefull thing !!! Remote control !!!

Guests won't have a remote control nor will they have the keypad
combination.

 

[Elmo]

On Mon, 01 Feb 2010 20:16:20 -0500, news@jecarter.us wrote:

Could be like the gate at a corporate site I occasionally visit - for
entry, you speak to a guard and show ID via a TV camera and the guard
opens the gate. A device like the one in this thread is used to allow
people to exit the gate.

Yes. The "typical" gate setup is:

1a. Owner approaches gate and flips remote control to get in.
1b. Utility truck approaches gate and pushed their logged 4-digit combo on
the digital keypad to get in (whether or not someone is home)
1c. Guest arrives and has to press the intercom button and can only be let
in if someone inside the house provides them access. Guest then pushes a
button on the keypad to open the gate.

2. In all cases above, the gate closes 25 seconds after it was opened.

3. In all cases above, when the owner/utility/guest leaves, the gate
automatically opens for them via the exit want magnetic field disturbance
sensor.

At least that's how my gate is set up. Some are set up to open via
cellphone but mine isn't fancy.

 

[Jeff Liebermann]

On Mon, 1 Feb 2010 15:15:51 +0000 (UTC), Elmo
<dcdraftworks@Use-Author-Supplied-Address.invalid> wrote:

I bought too short of a driveway-gate exit wand (GTO FM139 = 50 feet); I
need 150 feet.

Nobody told me (so I'm saying it here), one really needs about 150 feet if
they want the driveway gate to be open by the time the moving mass of metal
(i.e., automobile) reaches the gate. Lesson learned.

I suppose it's too late to exchange the exit wand.

Researching the web, it appears GTO sells three wands:
http://www.gtopro.com/access_controls.htm
- FM139 = 50 feet wired (about $180)
- FM140 = 100 feet wired (about $200)
- FM141 = 150 feet wired (about $225)

The instructions say you can not splice additional lengths
(http://www.gtopro.com/PDF/Flyers/Gate-Opener-Access-Control-FM139-vehicle-sensor.pdf

Yep. For good reason. The contraption belches RF somewhere between
20Khz and 150Khz and is similar to the vehicle detectors used for
traffic signal control. The mass of the vehicle detunes the coil
resulting in an increase in oscillator gate(?) current. In other
words, the whole mess, including the cable, is part of a resonant
circuit.

If you were able to rip apart the tube, you'll probably find an iron
core, with a zillion turns of wires wrapped around it. There will
also be a tuning capacitor, which is the key problem. Each length of
cable will have a different tuning capacitor, where the difference in
lengths is roughly equal to the difference in capacitance. These
differences are compensated by the internal tuning cap. If you're
lucky, they may have jumpers inside to select different cable lengths.
If the designer is really cool, the capacitor might be inside the
controller.

You might be able to get some clues if there are any patent numbers of
FCC ID numbers on the devices. I couldn't find anything registered to
"Gates That Open".

Calling www.gtopro.com technical support at 800-543-4283, they say there is
no difference between the wands or the wire other than the length BUT if I
splice in a wire, it won't work.

They may be right. 100ft of untwisted parallel cheezy wire is good
for about 500pf or so. That's quite a bit and will seriously affect
the resonant frequency of the wand. However, if the support droid is
telling the truth, then there should be a jumper or adjustment inside
the controller box for different lengths of cable. The manuals are
useless. So, you get to rip it open. Learn By Destroying(tm).

The technical support guy was very helpful. He said the reason it won't
work is that the "sensitivity of the magnetic field" changes with the
splice.

Baloney. Well, maybe 50% baloney. The resonant frequency will
change, and therefore, so will the sensitivity.

I don't understand why (if I make a good splice) but maybe there is
something about magnetic fields I don't understand that you can elucidate
for me? The wire is 5 conductor 16awg multi-strand shielded.

It's not the splice. It's the added capacitance wrecking the
resonance.

What is it about a splice that destroys the magnetic field?

Nope.

--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558
# http://802.11junk.com jeffl@cruzio.com
# http://www.LearnByDestroying.com AE6KS

 

[Jeff Liebermann]

On Mon, 01 Feb 2010 23:08:04 -0800, Jeff Liebermann <jeffl@cruzio.com>
wrote:

The instructions say you can not splice additional lengths
(http://www.gtopro.com/PDF/Flyers/Gate-Opener-Access-Control-FM139-vehicle-sensor.pdf

Yep. For good reason. The contraption belches RF somewhere between
20Khz and 150Khz and is similar to the vehicle detectors used for
traffic signal control. The mass of the vehicle detunes the coil
resulting in an increase in oscillator gate(?) current. In other
words, the whole mess, including the cable, is part of a resonant
circuit.

Ok, I lied. It's not the added capacitance. It's the added
inductance of the 100ft of feed cable. The destructions for a
different type of loop at:
<http://www.hooverfence.com/gtopro/manual/loopdt1-manual.pdf>
show an inductance of 0.22 microhenries per foot for the connecting
cable (presumably the same cable for both types of loops). That's
quite a bit of added inductance. I'm guessing, but it looks like the
target value for the loop and cable feed is about 100 microhenries.

Either way, adding the 100ft of cable is not going to work.

--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558
# http://802.11junk.com jeffl@cruzio.com
# http://www.LearnByDestroying.com AE6KS

 

[Jeff Liebermann]

On Mon, 01 Feb 2010 23:21:31 -0800, Jeff Liebermann <jeffl@cruzio.com>
wrote:

Ok, I lied. It's not the added capacitance. It's the added
inductance of the 100ft of feed cable. The destructions for a
different type of loop at:
http://www.hooverfence.com/gtopro/manual/loopdt1-manual.pdf
show an inductance of 0.22 microhenries per foot for the connecting
cable (presumably the same cable for both types of loops). That's
quite a bit of added inductance. I'm guessing, but it looks like the
target value for the loop and cable feed is about 100 microhenries.

Looks like the oscillation frequency is dependent on the loop
inductance. I (wrongly) assumed it was a fixed frequency (to make the
FCC happy). That means you could probably extend the cable feed and
all that will happen is that the oscillation frequency will be
drastically lowered. I don't know if that's going to cause a problem
with whatever they use for a detector, but it just might work.
However, if the new lower frequency causes airplanes to fall out of
sky, I suggest you instead purchase the correct exit sensor.

--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558
# http://802.11junk.com jeffl@cruzio.com
# http://www.LearnByDestroying.com AE6KS

 

[PeterD]

On Tue, 2 Feb 2010 05:56:54 +0000 (UTC), Elmo
<dcdraftworks@Use-Author-Supplied-Address.invalid> wrote:

On Mon, 01 Feb 2010 17:53:54 GMT, GregS wrote:

Whats the connector look like ??

There is no connector. Each of the four 16 AWG multi-stranded wires arrives
from the factory stripped of about 1/4 inch at the ends and tinned solid.

We just screw those four wires plus the shield into connections on the gate
opener motherboard.

The simple answer is just try it! What do you loose, a few minutes of
time?

That said, just make sure your splice is absolutely waterproof. 3M
makes underground splice kits that may work (used primarily for telco
work).

 

[William Sommerwerck]

Why has no one paid attention to my suggestion?

Get the manufacturer to give you full credit towards a longer cable.

 

[Elmo]

On Tue, 02 Feb 2010 08:39:31 -0500, PeterD wrote:

just make sure your splice is absolutely waterproof.
3M makes underground splice kits that may work

I have to find the 4-wire multi-stranded shielded cable first ... but I
will try the splice kit at the same time if I can find that also.

This morning I called GTO technical support again at 800-543-1236 and spoke
this time with a woman with a southern accent who told me a splice could be
done, but she said the problem is that it will eventually break. And, since
it will be underground, I won't know where it is and I'll be calling
technical support who won't know that it was spliced while they
troubleshoot.

When I asked "but CAN it be spliced?", she confirmed there is no difference
in the wand itself between the longer lengths of wire as the sensitivity
adjustments are done on the gate control board itself.

I'll look for that 3M waterproof splice kit. I think I'll need a
low-voltage splice kit. According to this web site, the voltage is 8 to 32
VAC or 8 to 26 VDC with a miniscule current of 1.5ma.
http://www.allsecurityequipment.com/proddetail.asp?prod=GTO-FM141

 

[Elmo]

On Mon, 01 Feb 2010 23:08:04 -0800, Jeff Liebermann wrote:

I suppose it's too late to exchange the exit wand.

I'm checking up on this right now.