On Fri, 09 May 2014 14:11:43 -0700, Jeff Liebermann
wrote:

On Fri, 09 May 2014 13:49:47 -0700, Jim Thompson
wrote:

Genie Model 2024

Can you simply buy a 433MHz receiver that has a relay output?

...Jim Thompson

They're all over eBay in many different configurations.
www.ebay.com/sch/i.html?_nkw=wireless+remote+switch

The problem will be getting one that is compatible with your cars
Homelink remote. That means you'll need to buy both the receiver and
transmitter because the transmitter is needed to program the Homelink
thing. However, if you're not going to use Homelink, then it's not an
issue.

Also, methinks we might be wrong about the frequency. The Genie 2024
runs on 390 MHz or possibly 315 MHz frequency. Genie got into
problems in areas where the military was using 390 MHz for something.
I'm not sure as I couldn't find any specific references. I could
lookup what it does by the FCC ID number, or you could just hang a
frequency counter near the trasmitter and see what frequency the
remote belches.

Looks like this will do it...

http://tinyurl.com/ll3dunj

or this one is cheaper...

http://tinyurl.com/mj7dcg9


...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| San Tan Valley, AZ 85142 Skype: Contacts Only | |
| Voice480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

In article ,
says...

amdx wrote:

On 5/8/2014 1:25 PM, WangoTango wrote:
In article , To-Email-Use-
says...
This new, very well-insulated, foil-backed, house has one drawback...
the garage door opener range with the garage door closed is only about
20'

Any ideas on how I could extend that range?

...Jim Thompson

An external antenna would be the easiest thing.


I'm with you, antenna is the solution.
I'd try cutting a director and reflector to proper lengths
and just hung then in place for a test.
Two pieces of wire could solve his problem.


That will detune the front end since it wasn't designed for a
complex, 50 ohm antenna. Some of the single board controllers have an
etched trace for the antenna. Also, any physical modification voids the
FCC acceptance. Some of these are super regen, and a better antenna will
radiate crap that will cause interference.


That's a lot of speculation and maybes.
How about he look at what he has and goes from there.
I'll bet it is one of the single chip code hopping solutions from any
one of a bunch of manufacturers and I doubt that it will be a super-
regen anything.
And, he didn't say that he cared if the FCC might not like the mod.

On 10/05/14 04:21, Jeff Liebermann wrote:
On Fri, 09 May 2014 20:41:15 +0300, wrote:

Do you believe the numbers it is giving you? 5.19 dB for a 1/4 wave ground
plane antenna? Also, gain is in dB, not dBm. Just a little nit.

It is not that far away, assuming perfect ground, which explains the
lower lobe to reflected upwards, which would explain 3 dB of gain. The
remaining 2.19 dB sounds much like the dipole gain over an isotropic
radiator. So actually, we should talk about 5.19 dBi gain or actually
_directivity_.

Good explanation and you're correct about the directivity. Having
gain in the wrong direction isn't very useful. In the case of the
shortened monopole, the peak gain is in roughly the correct direction
needed to be useful, so it's not an issue. However, other antenna
configurations can cause problems. For example, here's an animated
GIF of a common discone antenna.

Where?

Up to about 400 MHz, the major lobe
(i.e. maximum gain) is roughly horizontal, making the antenna quite
useable. However, between 400 and 1000 MHz, most of the RF goes
straight up. There's little RF left at the horizon, where it's
needed. Such an antenna might be good for listening to airplanes, but
not terrestrial stations.

For electrically small antennas, the efficiency can be
much less than 100 %, thus the _gain_ would be less.

The radiation efficiency and internal losses are included in the gain
calculation. For example, if I made the antenna from lossy material,
it would show up as a loss in gain. However, for a fairly close to
ideal antenna, the radiation efficiency barely changes.

wavelengths gain Efficiency Radiation
(db) Efficiency
0.250 5.19 100% 99.93%
0.125 4.85 100% 99.66%
0.050 4.75 100% 99.09%

Again, the problem is matching the impedance of the shortened antenna.
The losses are not in the antenna. They're in the matching circuit.

wavelengths gain(db) VSWR
(50ohms)
0.250 5.19 1.74:1
0.125 4.85 158:1
0.050 4.75 5954:1

I'm curious how you calculate these values?

The 0.050 wavelength monopole shows a feed impedance of 1.52-j707
which is going to be verrrrrry difficult to match efficiently to 50
ohms. Got a 500:1 transformer handy?

On 10/05/14 08:03, amdx wrote:
On 5/9/2014 3:49 PM, Jim Thompson wrote:
On Fri, 09 May 2014 15:38:43 -0500, amdx wrote:
On 5/9/2014 1:25 PM, Jim Thompson wrote:
Suppose I simply made a dipole half inside and half outside? Would
that improve my reception?
What is the model # of your opener, Let's find out what the output
circuit looks like.
Here's a few,
http://tinyurl.com/mwcbr2o
Genie Model 2024
Can you simply buy a 433MHz receiver that has a relay output?
Looks like about 9 wires to move the control circuit board, includes
the receiver, outside.

Does that leave two wires a crook could short to open the door?
Important not to forget the "other" reason for a door opener...

http://lib.store.yahoo.net/lib/yhst-...ion-manual.pdf

Looks pretty simple to remove, pull it out and inspect, maybe draw a
schematic.

I got that pdf from here
http://www.northshorecommercialdoor....adoop37co.html



I didn't find a schematic.





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On 09/05/2014 17:10, Jeff Liebermann wrote:
On Fri, 09 May 2014 12:02:50 +0100, Mike Perkins
wrote:

http://802.11junk.com/jeffl/antennas/Monopole/index.html

What is the software model you've used here?

4NEC2:
http://www.qsl.net/4nec2/
4NEC2 does not have an easy way to produce presentable web pages, so I
screen grabbed the JPG's using Irfanview and assembled the web page
with jAlbum.

I also use EZNEC:
http://www.eznec.com

Many thanks for the info.

--
Mike Perkins
Video Solutions Ltd
www.videosolutions.ltd.uk

On Sat, 10 May 2014 09:44:44 +1000, Clifford Heath
wrote:

On 10/05/14 04:21, Jeff Liebermann wrote:
Good explanation and you're correct about the directivity. Having
gain in the wrong direction isn't very useful. In the case of the
shortened monopole, the peak gain is in roughly the correct direction
needed to be useful, so it's not an issue. However, other antenna
configurations can cause problems. For example, here's an animated
GIF of a common discone antenna.

Where?

Sorry. Here's the missing link:
http://802.11junk.com/jeffl/antennas/Discone/slides/discone-animated.html
http://802.11junk.com/jeffl/antennas/Discone/index.html

Up to about 400 MHz, the major lobe
(i.e. maximum gain) is roughly horizontal, making the antenna quite
useable. However, between 400 and 1000 MHz, most of the RF goes
straight up. There's little RF left at the horizon, where it's
needed. Such an antenna might be good for listening to airplanes, but
not terrestrial stations.

wavelengths gain Efficiency Radiation
(db) Efficiency
0.250 5.19 100% 99.93%
0.125 4.85 100% 99.66%
0.050 4.75 100% 99.09%

Again, the problem is matching the impedance of the shortened antenna.
The losses are not in the antenna. They're in the matching circuit.

wavelengths gain(db) VSWR
(50ohms)
0.250 5.19 1.74:1
0.125 4.85 158:1
0.050 4.75 5954:1

I'm curious how you calculate these values?

4NEC2 does the number crunching for me. I would hate to do the
calculations by hand or with a calculator. I'm not even sure that I
could do them.

The VSWR and Efficiencies are show in the "Main" page. More on
radiation and power efficiency:
http://www.antennex.com/w4rnl/col0504/amod75.html

0.250 wavelength:
http://802.11junk.com/jeffl/antennas/Monopole/monopole_0_250/index.html
http://802.11junk.com/jeffl/antennas...ole_0_250.html

0.125 wavelength
http://802.11junk.com/jeffl/antennas/Monopole/monopole_0_125/index.html
http://802.11junk.com/jeffl/antennas...ole_0_125.html

0.050 wavelength
http://802.11junk.com/jeffl/antennas/Monopole/monopole_0_050/index.html
http://802.11junk.com/jeffl/antennas/Monopole/monopole_0_050/slides/monopole_0_050.html

Mo
http://802.11junk.com/jeffl/antennas/Monopole/index.html

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

On Fri, 9 May 2014 16:29:53 -0400, "Tom Miller"
wrote:


wrote in message
.. .
On Fri, 09 May 2014 11:21:13 -0700, Jeff Liebermann
wrote:

On Fri, 09 May 2014 20:41:15 +0300, wrote:

Do you believe the numbers it is giving you? 5.19 dB for a 1/4 wave
ground
plane antenna? Also, gain is in dB, not dBm. Just a little nit.

It is not that far away, assuming perfect ground, which explains the
lower lobe to reflected upwards, which would explain 3 dB of gain. The
remaining 2.19 dB sounds much like the dipole gain over an isotropic
radiator. So actually, we should talk about 5.19 dBi gain or actually
_directivity_.

Good explanation and you're correct about the directivity. Having
gain in the wrong direction isn't very useful. In the case of the
shortened monopole, the peak gain is in roughly the correct direction
needed to be useful, so it's not an issue. However, other antenna
configurations can cause problems. For example, here's an animated
GIF of a common discone antenna. Up to about 400 MHz, the major lobe
(i.e. maximum gain) is roughly horizontal, making the antenna quite
useable. However, between 400 and 1000 MHz, most of the RF goes
straight up. There's little RF left at the horizon, where it's
needed. Such an antenna might be good for listening to airplanes, but
not terrestrial stations.

For electrically small antennas, the efficiency can be
much less than 100 %, thus the _gain_ would be less.

The radiation efficiency and internal losses are included in the gain
calculation. For example, if I made the antenna from lossy material,
it would show up as a loss in gain. However, for a fairly close to
ideal antenna, the radiation efficiency barely changes.

wavelengths gain Efficiency Radiation
(db) Efficiency
0.250 5.19 100% 99.93%
0.125 4.85 100% 99.66%
0.050 4.75 100% 99.09%

Again, the problem is matching the impedance of the shortened antenna.
The losses are not in the antenna. They're in the matching circuit.

wavelengths gain(db) VSWR
(50ohms)
0.250 5.19 1.74:1
0.125 4.85 158:1
0.050 4.75 5954:1

Most of this VSWR is due to the fact that the small antenna has a high
(capacitive) reactance. Tuning it out with a loading coil, you only
have a smallish resistance mismatch and hence much lower VSWR.

The 0.050 wavelength monopole shows a feed impedance of 1.52-j707
which is going to be verrrrrry difficult to match efficiently to 50
ohms. Got a 500:1 transformer handy?

You tune out the capacitive -j707 ohms with a loading coil +j707 ohms
and you only have to worry about the resistive 1.52 ohms. To match
this to a 50 ohm input, the impedance ratio would be 1.52:50 or 1:33
or less than 1:6 turns ratio.

A few cm long "rubber duck" (normal mode helix) is a reasonably
efficient antenna for 433 MHz.


But only for certain values of "reasonably" .


Depending of your size constraints, even -10 dB or -20 dB antennas
might be acceptable.

Of course, no such constraints should exist for a fixed, big (garage
door) antenna.

On 2014-05-09, Jim Thompson wrote:
On Fri, 09 May 2014 15:38:43 -0500, amdx wrote:


Genie Model 2024

Can you simply buy a 433MHz receiver that has a relay output?

I got one for my dad's gate, his Door remote was branded Dominator, so,
probably uses a different code sequence to Genie. I can't spot the
receiver modiule on-line (I got mine over the counter from the
Dominator agent).

OTOH you could just get a 433MHz receiver module and a transmitter
replace the transmitter antenna with something worse than what it
comes with abd wire them together far enough apart that the receiver
can't see the transmitter,


--
umop apisdn


--- news://freenews.netfront.net/ - complaints: ---

On 2014-05-09, Jim Thompson wrote:

First, try a simple experiment. Open the garage door wide and test
the range of your unspecified model garage door opener radio. If you
get normal ranges (200ft or more), then the problem is the garage door
shielding. However, if the range is the same, the tuning on either
the transmitter or receiver is off frequency.

Dramatic range improvement.

that confirms it's a "antenna in a metal box" problem

How about this... Drill hole in door, fit water-tight thru-hole BNC
connector, attach rubber ducky antennas to each side. Would that be
enough of a "window"?

I'm thinking that be the eqivalent of about a 4" window in your door.


It'd work better if the indoor antenna was closer to the receiver.
I'd be considering putting the indoor antenna in the near field of
the receiver antenna. (but only after rejecting a direct connection to
the receiver circuit)


You've got inverse square law losses between you and the outdoor
antenna and again between the indooor antenna and the receiver.


Moving the indoor end of your passive repeater to where it does most
good has got to be good for a 30db reduction in loss.

--
umop apisdn

On Fri, 09 May 2014 16:07:54 -0700, Jim Thompson
wrote:

or this one is cheaper...
http://tinyurl.com/mj7dcg9

I like that one (for no obvious reason because there are no specs).

Is the metal part of the garage door insulated from the metal support
frame? Usually, that requires rubber or plastic wheels in the door
track. If so, you might be able to simply connect the antenna
connection to the overhead track arm, which is connected to the door.
The idea is to turn the metal door into an antenna. It won't be
efficient, matched, kosher, elegant, or otherwise according to the
textbook, but it will put the RF on the outside of the garage, which
methinks is the basic problem. Try it with a clip lead and hope that
the receiver tuning is sufficiently isolated from the antenna to not
become detuned (or oscillatory). My only worry is that if someone
dumps a static discharge into the door, it might blow up the receiver
front end.





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

On Fri, 09 May 2014 22:52:54 -0700, Jeff Liebermann
wrote:

On Fri, 09 May 2014 16:07:54 -0700, Jim Thompson
wrote:

or this one is cheaper...
http://tinyurl.com/mj7dcg9

I like that one (for no obvious reason because there are no specs).

Oh-oh. Kinda looks like BFT no longer sells a BFT-1. Nothing on
their web pile:
http://www.bft-usa.com/jsp/en/scheda/accessories-receivers_-_id_79.jsp
No manuals or any reference to a BFT-1 on their site.


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

On Fri, 09 May 2014 22:52:54 -0700, Jeff Liebermann
wrote:

On Fri, 09 May 2014 16:07:54 -0700, Jim Thompson
wrote:

or this one is cheaper...
http://tinyurl.com/mj7dcg9

I like that one (for no obvious reason because there are no specs).

Is the metal part of the garage door insulated from the metal support
frame? Usually, that requires rubber or plastic wheels in the door
track. If so, you might be able to simply connect the antenna
connection to the overhead track arm, which is connected to the door.
The idea is to turn the metal door into an antenna. It won't be
efficient, matched, kosher, elegant, or otherwise according to the
textbook, but it will put the RF on the outside of the garage, which
methinks is the basic problem. Try it with a clip lead and hope that
the receiver tuning is sufficiently isolated from the antenna to not
become detuned (or oscillatory). My only worry is that if someone
dumps a static discharge into the door, it might blow up the receiver
front end.

Interesting thought. A schematic of the controller board would be
most helpful.

...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| San Tan Valley, AZ 85142 Skype: Contacts Only | |
| Voice480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

WangoTango wrote:

In article ,
says...

amdx wrote:

On 5/8/2014 1:25 PM, WangoTango wrote:
In article , To-Email-Use-
says...
This new, very well-insulated, foil-backed, house has one drawback...
the garage door opener range with the garage door closed is only about
20'

Any ideas on how I could extend that range?

...Jim Thompson

An external antenna would be the easiest thing.


I'm with you, antenna is the solution.
I'd try cutting a director and reflector to proper lengths
and just hung then in place for a test.
Two pieces of wire could solve his problem.


That will detune the front end since it wasn't designed for a
complex, 50 ohm antenna. Some of the single board controllers have an
etched trace for the antenna. Also, any physical modification voids the
FCC acceptance. Some of these are super regen, and a better antenna will
radiate crap that will cause interference.


That's a lot of speculation and maybes.
How about he look at what he has and goes from there.
I'll bet it is one of the single chip code hopping solutions from any
one of a bunch of manufacturers and I doubt that it will be a super-
regen anything.
And, he didn't say that he cared if the FCC might not like the mod.


How many have you worked on?


--
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Jim Thompson wrote:

Interesting thought. A schematic of the controller board would be
most helpful.


You might find a schematic on the FCC database. Some items include
one in the OEM's filing.


--
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have a DD214, and a honorable discharge.

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On 5/10/2014 9:30 AM, Jim Thompson wrote:
On Fri, 09 May 2014 22:52:54 -0700, Jeff Liebermann
wrote:

On Fri, 09 May 2014 16:07:54 -0700, Jim Thompson
wrote:

or this one is cheaper...
http://tinyurl.com/mj7dcg9

I like that one (for no obvious reason because there are no specs).

Is the metal part of the garage door insulated from the metal support
frame? Usually, that requires rubber or plastic wheels in the door
track. If so, you might be able to simply connect the antenna
connection to the overhead track arm, which is connected to the door.
The idea is to turn the metal door into an antenna. It won't be
efficient, matched, kosher, elegant, or otherwise according to the
textbook, but it will put the RF on the outside of the garage, which
methinks is the basic problem. Try it with a clip lead and hope that
the receiver tuning is sufficiently isolated from the antenna to not
become detuned (or oscillatory). My only worry is that if someone
dumps a static discharge into the door, it might blow up the receiver
front end.

Interesting thought. A schematic of the controller board would be
most helpful.

...Jim Thompson

If you looked at the PDF I posted, it shows how to remove the
controller/transmitter pcb. Take it out and see how complex it is.
You know how to draw schematic, I can't read them,
but you know how :-)
Mikek
Mikek

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"John Larkin" wrote in message
...
On Wed, 07 May 2014 16:40:39 -0700, Jim Thompson
wrote:

On Wed, 07 May 2014 16:30:35 -0700, John Larkin
wrote:

On Wed, 07 May 2014 13:27:29 -0700, Jim Thompson
wrote:

This new, very well-insulated, foil-backed, house has one drawback...
the garage door opener range with the garage door closed is only about
20'

Any ideas on how I could extend that range?

...Jim Thompson

You need an engineer!

Always have to go out of your way to be a turd, don't you... sad
specimen you are.

...Jim Thompson

Geez, you have an antenna inside a metal box, and you need advice?


Heh heh heh.

On 10/05/14 11:21, Jeff Liebermann wrote:
On Sat, 10 May 2014 09:44:44 +1000, Clifford Heath
Again, the problem is matching the impedance of the shortened antenna.
The losses are not in the antenna. They're in the matching circuit.
wavelengths gain(db) VSWR
(50ohms)
0.250 5.19 1.74:1
0.125 4.85 158:1
0.050 4.75 5954:1
I'm curious how you calculate these values?
4NEC2 does the number crunching for me. I would hate to do the
calculations by hand or with a calculator. I'm not even sure that I
could do them.

Thanks. I'll have to get a version that works for me (on Mac).

I was curious that the VSWR seems to go roughly as the inverse third
power of length, which made it seem like a simple formula could
approximate it.

Clifford Heath.

On Tue, 13 May 2014 11:44:57 +1000, Clifford Heath
wrote:

On 10/05/14 11:21, Jeff Liebermann wrote:
On Sat, 10 May 2014 09:44:44 +1000, Clifford Heath
Again, the problem is matching the impedance of the shortened antenna.
The losses are not in the antenna. They're in the matching circuit.
wavelengths gain(db) VSWR
(50ohms)
0.250 5.19 1.74:1
0.125 4.85 158:1
0.050 4.75 5954:1
I'm curious how you calculate these values?
4NEC2 does the number crunching for me. I would hate to do the
calculations by hand or with a calculator. I'm not even sure that I
could do them.

Thanks. I'll have to get a version that works for me (on Mac).

I was curious that the VSWR seems to go roughly as the inverse third
power of length, which made it seem like a simple formula could
approximate it.

Clifford Heath.

First of all, you need to kill the reactive impedance, for a short
antenna with a suitable inductance.

Secondly, you need to match the antenna impedance (in a small antenna
usually a few ohms) with the receiver/transmitter 50 ohms resistive
impedance.

A pi (series L with C to ground) or a T (series C and L to ground)
will do the trick for a narrow band application.

In article ,
says...

WangoTango wrote:

In article ,
says...

amdx wrote:

On 5/8/2014 1:25 PM, WangoTango wrote:
In article , To-Email-Use-
says...
This new, very well-insulated, foil-backed, house has one drawback...
the garage door opener range with the garage door closed is only about
20'

Any ideas on how I could extend that range?

...Jim Thompson

An external antenna would be the easiest thing.


I'm with you, antenna is the solution.
I'd try cutting a director and reflector to proper lengths
and just hung then in place for a test.
Two pieces of wire could solve his problem.


That will detune the front end since it wasn't designed for a
complex, 50 ohm antenna. Some of the single board controllers have an
etched trace for the antenna. Also, any physical modification voids the
FCC acceptance. Some of these are super regen, and a better antenna will
radiate crap that will cause interference.


That's a lot of speculation and maybes.
How about he look at what he has and goes from there.
I'll bet it is one of the single chip code hopping solutions from any
one of a bunch of manufacturers and I doubt that it will be a super-
regen anything.
And, he didn't say that he cared if the FCC might not like the mod.


How many have you worked on?

One more than you have.

WangoTango wrote:

In article ,
says...

WangoTango wrote:

In article ,
says...

amdx wrote:

On 5/8/2014 1:25 PM, WangoTango wrote:
In article , To-Email-Use-
says...
This new, very well-insulated, foil-backed, house has one drawback...
the garage door opener range with the garage door closed is only about
20'

Any ideas on how I could extend that range?

...Jim Thompson

An external antenna would be the easiest thing.


I'm with you, antenna is the solution.
I'd try cutting a director and reflector to proper lengths
and just hung then in place for a test.
Two pieces of wire could solve his problem.


That will detune the front end since it wasn't designed for a
complex, 50 ohm antenna. Some of the single board controllers have an
etched trace for the antenna. Also, any physical modification voids the
FCC acceptance. Some of these are super regen, and a better antenna will
radiate crap that will cause interference.


That's a lot of speculation and maybes.
How about he look at what he has and goes from there.
I'll bet it is one of the single chip code hopping solutions from any
one of a bunch of manufacturers and I doubt that it will be a super-
regen anything.
And, he didn't say that he cared if the FCC might not like the mod.


How many have you worked on?

One more than you have.

If that were true, you would know how sensitive the front end is to
detuning. The additional capacitance of coax would take it out of band
without reducing the inductance in the tuned circuit. BTW, I repaired
hundreds of the damned things for a garage door company that was owned
by a friend. I repaired stuff from early tube designs, up to rolling
code. From single function, to specials models that controlled eight
doors for firehouses.


--
Anyone wanting to run for any political office in the US should have to
have a DD214, and a honorable discharge.

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On Fri, 16 May 2014 11:01:42 -0400, "Michael A. Terrell"
wrote:

If that were true, you would know how sensitive the front end is to
detuning. The additional capacitance of coax would take it out of band
without reducing the inductance in the tuned circuit.

That was certainly true of previous generations of remote control
receivers. I fixed a few of those (mostly by retuning). Most of the
few garage door and gate opener repairs I've done have been
mechanical, not electronic.

Times have changes. For keyless entry receivers, I'm seeing SAW
filters, superhets, one-chip receivers, etc. For example:
http://www.maximintegrated.com/datasheet/index.mvp/id/3104
http://www.maximintegrated.com/datasheet/index.mvp/id/5513
etc...

Whether Genie uses technology that's become standard for automobile
door openers and alarms is unknown. Schematics seem difficult to
find. Most of the receiver pictures of the boards I've found are
obviously TRF (tuned RF) receivers, which will have the detuning
problems you mentioned. The more modern opener that Jim bought seems
to have a more sophisticated receiver:
http://galleryplus.ebayimg.com/ws/web/301060926645_1_0_1/1000x1000.jpg
The black wire on the left is the antenna. Most of the receiver is
covered but I can see the leads of an SOT device nearby and no
adjustable coils near the antenna lead. That suggests a more modern
design, probably using one of the aforementioned integrated receivers,
which will not have antenna detuning issues.

BTW, I repaired
hundreds of the damned things for a garage door company that was owned
by a friend. I repaired stuff from early tube designs, up to rolling
code. From single function, to specials models that controlled eight
doors for firehouses.

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

On Fri, 16 May 2014 08:59:04 -0700, Jeff Liebermann
wrote:

On Fri, 16 May 2014 11:01:42 -0400, "Michael A. Terrell"
wrote:

If that were true, you would know how sensitive the front end is to
detuning. The additional capacitance of coax would take it out of band
without reducing the inductance in the tuned circuit.

That was certainly true of previous generations of remote control
receivers. I fixed a few of those (mostly by retuning). Most of the
few garage door and gate opener repairs I've done have been
mechanical, not electronic.

Times have changes. For keyless entry receivers, I'm seeing SAW
filters, superhets, one-chip receivers, etc. For example:
http://www.maximintegrated.com/datasheet/index.mvp/id/3104
http://www.maximintegrated.com/datasheet/index.mvp/id/5513
etc...

Whether Genie uses technology that's become standard for automobile
door openers and alarms is unknown. Schematics seem difficult to
find. Most of the receiver pictures of the boards I've found are
obviously TRF (tuned RF) receivers, which will have the detuning
problems you mentioned. The more modern opener that Jim bought seems
to have a more sophisticated receiver:
http://galleryplus.ebayimg.com/ws/web/301060926645_1_0_1/1000x1000.jpg
The black wire on the left is the antenna. Most of the receiver is
covered but I can see the leads of an SOT device nearby and no
adjustable coils near the antenna lead. That suggests a more modern
design, probably using one of the aforementioned integrated receivers,
which will not have antenna detuning issues.

BTW, I repaired
hundreds of the damned things for a garage door company that was owned
by a friend. I repaired stuff from early tube designs, up to rolling
code. From single function, to specials models that controlled eight
doors for firehouses.

The problem is further reduced. Finally got the programming to take
on the HomeLink transmitter in my Q45 (using the programming technique
Jeff found)... the range is substantially increased.

So, either batteries in Genie fobs are weak, or transmitter design is
weenie. (Q45 is 9 years old... who knows what emasculation has been
done to transmitters by the FCC since then.)

...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| San Tan Valley, AZ 85142 Skype: Contacts Only | |
| Voice480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

In article ,
says...

WangoTango wrote:

In article ,
says...

WangoTango wrote:

In article ,
says...

amdx wrote:

On 5/8/2014 1:25 PM, WangoTango wrote:
In article , To-Email-Use-
says...
This new, very well-insulated, foil-backed, house has one drawback...
the garage door opener range with the garage door closed is only about
20'

Any ideas on how I could extend that range?

...Jim Thompson

An external antenna would be the easiest thing.


I'm with you, antenna is the solution.
I'd try cutting a director and reflector to proper lengths
and just hung then in place for a test.
Two pieces of wire could solve his problem.


That will detune the front end since it wasn't designed for a
complex, 50 ohm antenna. Some of the single board controllers have an
etched trace for the antenna. Also, any physical modification voids the
FCC acceptance. Some of these are super regen, and a better antenna will
radiate crap that will cause interference.


That's a lot of speculation and maybes.
How about he look at what he has and goes from there.
I'll bet it is one of the single chip code hopping solutions from any
one of a bunch of manufacturers and I doubt that it will be a super-
regen anything.
And, he didn't say that he cared if the FCC might not like the mod.


How many have you worked on?

One more than you have.

If that were true, you would know how sensitive the front end is to
detuning. The additional capacitance of coax would take it out of band
without reducing the inductance in the tuned circuit. BTW, I repaired
hundreds of the damned things for a garage door company that was owned
by a friend. I repaired stuff from early tube designs, up to rolling
code. From single function, to specials models that controlled eight
doors for firehouses.

That's awesome, but it has absolutely nothing to do with the problem at
hand, and that is Jim's SPECIFIC unit. Which is most likely NOT some
regenerative design.

I love cooking and really want to do it in my garage but I'm afraid I'l cause an accident like it's made of wood and I'm scared I'l do myself and the garage some harm. Is it really likely??

I had a lot of issues with my garage doors when I was making a new one at my place. I actually had it built by a vendor whom I found through the internet waterloostructures. net and they were going to do the doors for me but I wanted to do that myself so I tried I but was unlucky in fixing it successfully. So tough luck guys I'm still without a door and really ****ed off!! what to do???