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KPA500 mobile?

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Matt Zilmer-3

Re: KPA500 mobile?

Sirius (at least) has terrestrial transmitters that are used to full sat
voids, like tunnels or parts of the San Francisco or NY financial
districts, or tall mountains near an interstate highway. The smaller
blockages are probably deemed a minor inconvenience, especially if
they're out inthe countrysideor in unpopulated areas. I used Sirius in
the early 2000s, and used to experience regular dropouts of 4 seconds in
several locations on my commuteto/from work. Each of these areas was
under a highway or freeway.

Not sure if your tunnel was private or not. If it was, it wasn't
covered by surface transmitters unless by accident. There is a tunnel
in LA that basically runs under LAX, and I never lost signal there. It's
probably hit or miss on what's covered terrestrially.

XM (I believe) bought Sirius out, sometime in the last decade. Both
services operate on the abandoned telco S-bandif I understand
correctly. I hear XM isn't doing so well financially, but that was
probably a couple of years ago. May not be current on this.

73,

matt W6NIA

On 4/14/2017 8:47 PM, Fred Jensen wrote:

> Semi-related curiosity regarding shielding. My wife's car has
> Sirius/XM radio. It usually loses contact with the satellite driving
> under Interstate bridges and the like. Likewise in the garage. OTOH,
> at our previous home there was a tunnel through a small hill, perhaps
> 1/4 mi long. The XM worked fine through it. There are a pair of
> tunnels at Cave Rock next to Lake Tahoe through a granite mountain.
> XM works fine through them too. Anyone know why?
>
> 73,
>
> Fred ("Skip") K6DGW
> Sparks NV USA
> Washoe County DM09dn
>
> On 4/14/2017 2:50 PM, Phil Kane wrote:
>> On 4/14/2017 1:13 PM, KENT TRIMBLE wrote:
>>
>>> The assumption has always been that the driver and passengers are
>>> riding
>>> inside a Faraday Cage and therefore are safe from RF radiated by an HF
>>> antenna, regardless of where located and regardless of power level.
>> When I take my 2011 Ford Focus through the car wash, I put the mag-mount
>> VHF antenna inside the car but it is still connected to the radio. I
>> have no problem picking up the usual 2- and 3/4- meter repeaters that
>> way. So much for the "Faraday Cage". :)
>>
>> 73 de K2ASP - Phil Kane
>> Elecraft K2/100 s/n 5402
>>
>
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--
"A delay is better than a disaster."
-- unknonwn

Matt Zilmer, W6NIA
[Shiraz]

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Jim Brown-10

Re: KPA500 mobile?

On Fri,4/14/2017 9:06 PM, Matt Zilmer wrote:
> I used Sirius in the early 2000s, and used to experience regular
> dropouts of 4 seconds in several locations on my commuteto/from work.
> Each of these areas was under a highway or freeway.

I occasionally car pool to ham events with a neighbor in his high end
VW. He bought the satellite service, and we sometimes listen to it. It
drops out with foliage and under overpasses. Sound quality is so bad
that it's hard to listen to any form of acoustic music. Perhaps too much
data compression, made worse by any problems with the signal path.

73, Jim K9YC

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Luis V Romero (mobile)

Re: KPA500 mobile?

In reply to this post by Mike Smith VE9AA

Shameless Promotion but interesting story:

Two years ago in the Florida QSO Party, our local "Mad Scientist" and mobile
operations God Chris, NX4N, decided to do something that had never been done
before:

A Multi Multi mobile entry!

In his Chevy Suburban, we had four radios: A K3 in the front seat (K0LUZ), a
Pro2 (W4BP) and a K3 in the second row (K4KM) and me with a K3 in the third
row. 20m, 40m, 15m and 10m in that order. Chris did all the driving. It
was an all CW operation.

Lots of filtering and coax stubs installed. Four separate antennas on the
corners of the roof. Four separate computers. The KX3 was feeding a KPA500
in the back of the Suburban which turned it into a 100w radio. Power
supplies and other sundries were installed in a bread rack in the back and
secured by Bungie cords.

Feeding power to all of this was a Honda 2kW generator with an external fuel
tank mounted on a carrier attached to the trailer hitch. The generator was
covered by a plastic tub held on to the hitch carrier with Bungie cords.
This cover was for rain abatement. The cover was adorned with special vents
on the side. Yes, crazy and a gray area of mobile legality, But all of us
survived to tell the tale. And it was Great fun! And I remember working
OM2VL at almost every single county line.

It's the only time I have seen a KPA500 mobile.

I have since bowed out of this glorious extreme mobile engineering
achievement. But it continues with others to this day.

And it will be on this coming weekend in the Florida QSO Party's 20th
anniversary celebration.

The call sign used by this intrepid crew is K4OJ (in honor of FCG Founder
Jim White (SK)). Look for them this coming weekend!

Lu - W4LT
(W4I in the FQP - Spell "F-L-O-R-I-D-A S-U-N" with our 20 "letter
multiplier" stations -2 for each letter - for a special certificate!)

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Phil Hystad-3

Re: KPA500 mobile?

In reply to this post by k6dgw

A number of tunnels are “wired” for broadband radio reception. A bit of years ago when they were building the I-90 stretch between Bellevue and Seattle there are two major “tunnels” on each side of the I-90 floating bridge (across Lake Washington). The tunnel on Mercer Island is actually not a tunnel but a covered section of the freeway but the tunnel on the west end is through the hill (known as the Mount Baker tunnel but not because it is under Mount Baker but because it is under the Mount Baker neighborhood of Seattle).

So, a news article at the time described how the technology was employed to provide radio reception for AM, FM, and also cellular communication. I don’t remember reading about Sirius/XM radio though. I do know that my HF mobile operations come to a halt through those tunnels. As signals drop off after a 100 feet or so from the opening and don’t come back until the other side.

Unfortunately, I can’t remember anything of the details of how this was done but I suspect wide-band amplifiers and wires and top-side wide-band antennas.

73, phil, K7PEH

> On Apr 14, 2017, at 8:47 PM, Fred Jensen <[hidden email]> wrote:
>
> Semi-related curiosity regarding shielding. My wife's car has Sirius/XM radio. It usually loses contact with the satellite driving under Interstate bridges and the like. Likewise in the garage. OTOH, at our previous home there was a tunnel through a small hill, perhaps 1/4 mi long. The XM worked fine through it. There are a pair of tunnels at Cave Rock next to Lake Tahoe through a granite mountain. XM works fine through them too. Anyone know why?
>
> 73,
>
> Fred ("Skip") K6DGW
> Sparks NV USA
> Washoe County DM09dn
>
> On 4/14/2017 2:50 PM, Phil Kane wrote:
>> On 4/14/2017 1:13 PM, KENT TRIMBLE wrote:
>>
>>> The assumption has always been that the driver and passengers are riding
>>> inside a Faraday Cage and therefore are safe from RF radiated by an HF
>>> antenna, regardless of where located and regardless of power level.
>> When I take my 2011 Ford Focus through the car wash, I put the mag-mount
>> VHF antenna inside the car but it is still connected to the radio. I
>> have no problem picking up the usual 2- and 3/4- meter repeaters that
>> way. So much for the "Faraday Cage". :)
>>
>> 73 de K2ASP - Phil Kane
>> Elecraft K2/100 s/n 5402
>>
>
> ______________________________________________________________
> Elecraft mailing list
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Elecraft mailing list

Re: KPA500 mobile?

OTOH, this can be a feature of tunnels, not a bug. Several years ago I was riding on the “BikePike”, an abandoned section of the PA Turnpike east of Breezewood that has become a bicycle route featuring two old tunnels. Although closed off to motor vehicle traffic, we noticed a pickup parked outside the entrance to one of the tunnels. A few hundred yards into the tunnel we encountered a minivan with lots of high end electronic test equipment. Turns out the guys were doing tests on some military equipment, to determine that it was RF quiet to prevent detection by enemy forces. We didn’t ask a lot more, lest they would have had to shoot us :-)

73 - Jim K8MR

> On Apr 15, 2017, at 10:43 AM, Phil Hystad <[hidden email]> wrote:
>
> A number of tunnels are “wired” for broadband radio reception. A bit of years ago when they were building the I-90 stretch between Bellevue and Seattle there are two major “tunnels” on each side of the I-90 floating bridge (across Lake Washington). The tunnel on Mercer Island is actually not a tunnel but a covered section of the freeway but the tunnel on the west end is through the hill (known as the Mount Baker tunnel but not because it is under Mount Baker but because it is under the Mount Baker neighborhood of Seattle).
>
> So, a news article at the time described how the technology was employed to provide radio reception for AM, FM, and also cellular communication. I don’t remember reading about Sirius/XM radio though. I do know that my HF mobile operations come to a halt through those tunnels. As signals drop off after a 100 feet or so from the opening and don’t come back until the other side.
>
> Unfortunately, I can’t remember anything of the details of how this was done but I suspect wide-band amplifiers and wires and top-side wide-band antennas.
>
> 73, phil, K7PEH
>
>
>> On Apr 14, 2017, at 8:47 PM, Fred Jensen <[hidden email]> wrote:
>>
>> Semi-related curiosity regarding shielding. My wife's car has Sirius/XM radio. It usually loses contact with the satellite driving under Interstate bridges and the like. Likewise in the garage. OTOH, at our previous home there was a tunnel through a small hill, perhaps 1/4 mi long. The XM worked fine through it. There are a pair of tunnels at Cave Rock next to Lake Tahoe through a granite mountain. XM works fine through them too. Anyone know why?
>>
>> 73,
>>
>> Fred ("Skip") K6DGW
>> Sparks NV USA
>> Washoe County DM09dn

Phil Hystad-3

Re: KPA500 mobile? -- OT tunnel communications

I found one link that describes basically this service for AM/FM radio reception in the I-90 tunnels. It is section 7.3 (right near the end) of this link:

http://www.wsdot.wa.gov/sites/default/files/2012/06/26/I-90TunnelSystem.pdf

And, cellular service will be ultimately in all of the tunnels under Seattle and already exists in the oldest downtown tunnel as described here:

http://www.seattletimes.com/seattle-news/transportation/seattle-transit-tunnels-will-finally-get-cellphone-signals/

73, phil, K7PEH

> On Apr 15, 2017, at 8:14 AM, Jim Stahl <[hidden email]> wrote:
>
> OTOH, this can be a feature of tunnels, not a bug. Several years ago I was riding on the “BikePike”, an abandoned section of the PA Turnpike east of Breezewood that has become a bicycle route featuring two old tunnels. Although closed off to motor vehicle traffic, we noticed a pickup parked outside the entrance to one of the tunnels. A few hundred yards into the tunnel we encountered a minivan with lots of high end electronic test equipment. Turns out the guys were doing tests on some military equipment, to determine that it was RF quiet to prevent detection by enemy forces. We didn’t ask a lot more, lest they would have had to shoot us :-)
>
>
> 73 - Jim K8MR
>
>
>> On Apr 15, 2017, at 10:43 AM, Phil Hystad <[hidden email]> wrote:
>>
>> A number of tunnels are “wired” for broadband radio reception. A bit of years ago when they were building the I-90 stretch between Bellevue and Seattle there are two major “tunnels” on each side of the I-90 floating bridge (across Lake Washington). The tunnel on Mercer Island is actually not a tunnel but a covered section of the freeway but the tunnel on the west end is through the hill (known as the Mount Baker tunnel but not because it is under Mount Baker but because it is under the Mount Baker neighborhood of Seattle).
>>
>> So, a news article at the time described how the technology was employed to provide radio reception for AM, FM, and also cellular communication. I don’t remember reading about Sirius/XM radio though. I do know that my HF mobile operations come to a halt through those tunnels. As signals drop off after a 100 feet or so from the opening and don’t come back until the other side.
>>
>> Unfortunately, I can’t remember anything of the details of how this was done but I suspect wide-band amplifiers and wires and top-side wide-band antennas.
>>
>> 73, phil, K7PEH
>>
>>
>>> On Apr 14, 2017, at 8:47 PM, Fred Jensen <[hidden email]> wrote:
>>>
>>> Semi-related curiosity regarding shielding. My wife's car has Sirius/XM radio. It usually loses contact with the satellite driving under Interstate bridges and the like. Likewise in the garage. OTOH, at our previous home there was a tunnel through a small hill, perhaps 1/4 mi long. The XM worked fine through it. There are a pair of tunnels at Cave Rock next to Lake Tahoe through a granite mountain. XM works fine through them too. Anyone know why?
>>>
>>> 73,
>>>
>>> Fred ("Skip") K6DGW
>>> Sparks NV USA
>>> Washoe County DM09dn
>

Clay Autery

OT: Re: KPA500 mobile?

In reply to this post by k6dgw

I would think it would depend almost entirely on the orientation of the
tunnel... (and satellite reception azimuth).

First, the longest of those two tunnels is only 425 feet or so. The
other is significantly shorter (southbound).
The tunnels are oriented generally north/south which is the preferred
direction IF you have to monitor geosynchronous satellite transmissions
from overhead... sort of).
You are right on the edge of a large body of water, which while not
brine, has better conductivity than the soil around the lake.
Significant potential for reflections off the high ground on almost all
sides....

Don't know where that first tunnel is, so I can't comment. But if you
gotta hear in a tunnel.... those two would be great candidates...

73,

______________________
Clay Autery, KY5G
MONTAC Enterprises
(318) 518-1389

On 4/14/2017 10:47 PM, Fred Jensen wrote:

Clay Autery

Re: KPA500 mobile?

In reply to this post by Jim Brown-10

Hate to hear that... Wife loves it. (2014 Fusion). I'm mostly happy
with it, too. Though I prefer to just play what I want from my phone
(high bit-rate mp3). Of course, neither of us are audiophiles, and I
flew helicopters...

______________________
Clay Autery, KY5G
MONTAC Enterprises
(318) 518-1389

On 4/14/2017 11:41 PM, Jim Brown wrote:

> On Fri,4/14/2017 9:06 PM, Matt Zilmer wrote:
>> I used Sirius in the early 2000s, and used to experience regular
>> dropouts of 4 seconds in several locations on my commuteto/from
>> work. Each of these areas was under a highway or freeway.
>
> I occasionally car pool to ham events with a neighbor in his high end
> VW. He bought the satellite service, and we sometimes listen to it. It
> drops out with foliage and under overpasses. Sound quality is so bad
> that it's hard to listen to any form of acoustic music. Perhaps too
> much data compression, made worse by any problems with the signal path.
>
> 73, Jim K9YC

Clay Autery

Re: KPA500 mobile?

In reply to this post by Elecraft mailing list

The ultimate directional, high-pass filter... <grin>

______________________
Clay Autery, KY5G
MONTAC Enterprises
(318) 518-1389

On 4/15/2017 10:14 AM, Jim Stahl via Elecraft wrote:
> OTOH, this can be a feature of tunnels, not a bug. Several years ago I was riding on the “BikePike”, an abandoned section of the PA Turnpike east of Breezewood that has become a bicycle route featuring two old tunnels. Although closed off to motor vehicle traffic, we noticed a pickup parked outside the entrance to one of the tunnels. A few hundred yards into the tunnel we encountered a minivan with lots of high end electronic test equipment. Turns out the guys were doing tests on some military equipment, to determine that it was RF quiet to prevent detection by enemy forces. We didn’t ask a lot more, lest they would have had to shoot us :-)
>
>
> 73 - Jim K8MR

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Phil Kane-2

Re: KPA500 mobile?

In reply to this post by Phil Hystad-3

On 4/15/2017 7:43 AM, Phil Hystad wrote:

> Unfortunately, I can’t remember anything of the details of how this
> was done but I suspect wide-band amplifiers and wires and top-side
> wide-band antennas.

Leaky coax (trade name == Radiax). It's many-decades-old technology.

73 de K2ASP - Phil Kane
Elecraft K2/100 s/n 5402

From a Clearing in the Silicon Forest
Beaverton (Washington County) Oregon
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Phil Kane-2

Re: KPA500 mobile? -- OT tunnel communications

In reply to this post by Phil Hystad-3

On 4/15/2017 8:45 AM, Phil Hystad wrote:

> And, cellular service will be ultimately in all of the tunnels under
> Seattle and already exists in the oldest downtown tunnel as described
> here:

"All it takes is money...." (my favorite phrase)

Now if they were to fund ham-band repeaters - that would be something!

73 de K2ASP - Phil Kane
Elecraft K2/100 s/n 5402

From a Clearing in the Silicon Forest
Beaverton (Washington County) Oregon
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k6dgw

Re: OT: Re: KPA500 mobile?

In reply to this post by Clay Autery

Well, one of the side benefits of this list ... lots of smart and
knowledgeable people. A summary and then it can pass into the archive ...

1. The first of "my" tunnels is in Newcastle CA [between Auburn and
Sacramento on the old US40 and Lincoln Hwy route] and was constructed
sometime around the end of the 19th/beginning of the 20th centuries.
It's not quite 1/4 mile long. There is no visible wire or radiax in
it. The hill it runs thru is full of water and you get leaked on when
driving thru it, even in summer.

2. In the early 80's, the company I worked for then had a contract to
rehab the communications for the Bay Area Rapid Transit system. We used
a 300 ohm twinlead with a hollow core about 2 1/2 in in diameter along
the ceiling of the tunnels and underground sections. It was 150 MHz
land mobile stuff and the twinlead was fed from a combiner that put 5 or
6 transmitters into it [train control, fire, security, etc.] It worked
very well. Aligning the combiners [which actually looked a bit like a
still [:-) ] was a bear in the equipment spaces in the tube under SF Bay
but it worked well. They also wanted 800 MHz simulcast throughout the
service area, a requirement probably still waiting for a real solution.

3. Other than under bridges, in canyons, beside heavily forested roads,
and in the garage, where it's obvious the path to the satellite(s) is
blocked, we don't experience any XM drop outs. She's going to drop the
subscription, it's expensive and my new Honda Ridgeline has become our
travel vehicle, but she's had it since 2013.

4. I've wondered if there wasn't some sort of waveguide effect in
tunnels. For BART, one of the many problems we had with simulcast was
that it leaked into the tunnels, even as far as the bottom of the
Transbay tube. I don't know the XM satellite frequencies but I thought
they occupied some spectrum abandoned by the Cellphone industry.

5. [Bonus Factoid]: The pine forests of the Southeast US are opaque to
800 MHz.

Thanks for all the ideas and peripheral info.

73,

Fred ("Skip") K6DGW
Sparks NV USA
Washoe County DM09dn

On 4/15/2017 10:40 AM, Clay Autery wrote:

> I would think it would depend almost entirely on the orientation of the
> tunnel... (and satellite reception azimuth).
>
> First, the longest of those two tunnels is only 425 feet or so. The
> other is significantly shorter (southbound).
> The tunnels are oriented generally north/south which is the preferred
> direction IF you have to monitor geosynchronous satellite transmissions
> from overhead... sort of).
> You are right on the edge of a large body of water, which while not
> brine, has better conductivity than the soil around the lake.
> Significant potential for reflections off the high ground on almost all
> sides....
>
> Don't know where that first tunnel is, so I can't comment. But if you
> gotta hear in a tunnel.... those two would be great candidates...
>
> 73,
>
> ______________________
> Clay Autery, KY5G
> MONTAC Enterprises
> (318) 518-1389
>
> On 4/14/2017 10:47 PM, Fred Jensen wrote:
>> Semi-related curiosity regarding shielding. My wife's car has
>> Sirius/XM radio. It usually loses contact with the satellite driving
>> under Interstate bridges and the like. Likewise in the garage. OTOH,
>> at our previous home there was a tunnel through a small hill, perhaps
>> 1/4 mi long. The XM worked fine through it. There are a pair of
>> tunnels at Cave Rock next to Lake Tahoe through a granite mountain.
>> XM works fine through them too. Anyone know why?
>>
>> 73,
>>
>> Fred ("Skip") K6DGW
>> Sparks NV USA
>> Washoe County DM09dn
> ______________________________________________________________
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>

Matt Zilmer-3

Re: OT: Re: KPA500 mobile?

I think that both XM and Sirius were/are using 2.2 GHzor thereabouts.
It's not MSS territory, but it works if you have enough power behind it.

73,

matt W6NIA

On 4/15/2017 4:32 PM, Fred Jensen wrote:

> Well, one of the side benefits of this list ... lots of smart and
> knowledgeable people. A summary and then it can pass into the archive
> ...
>
> 1. The first of "my" tunnels is in Newcastle CA [between Auburn and
> Sacramento on the old US40 and Lincoln Hwy route] and was constructed
> sometime around the end of the 19th/beginning of the 20th centuries.
> It's not quite 1/4 mile long. There is no visible wire or radiax in
> it. The hill it runs thru is full of water and you get leaked on when
> driving thru it, even in summer.
>
> 2. In the early 80's, the company I worked for then had a contract to
> rehab the communications for the Bay Area Rapid Transit system. We
> used a 300 ohm twinlead with a hollow core about 2 1/2 in in diameter
> along the ceiling of the tunnels and underground sections. It was 150
> MHz land mobile stuff and the twinlead was fed from a combiner that
> put 5 or 6 transmitters into it [train control, fire, security, etc.]
> It worked very well. Aligning the combiners [which actually looked a
> bit like a still [:-) ] was a bear in the equipment spaces in the tube
> under SF Bay but it worked well. They also wanted 800 MHz simulcast
> throughout the service area, a requirement probably still waiting for
> a real solution.
>
> 3. Other than under bridges, in canyons, beside heavily forested
> roads, and in the garage, where it's obvious the path to the
> satellite(s) is blocked, we don't experience any XM drop outs. She's
> going to drop the subscription, it's expensive and my new Honda
> Ridgeline has become our travel vehicle, but she's had it since 2013.
>
> 4. I've wondered if there wasn't some sort of waveguide effect in
> tunnels. For BART, one of the many problems we had with simulcast was
> that it leaked into the tunnels, even as far as the bottom of the
> Transbay tube. I don't know the XM satellite frequencies but I
> thought they occupied some spectrum abandoned by the Cellphone industry.
>
> 5. [Bonus Factoid]: The pine forests of the Southeast US are opaque to
> 800 MHz.
>
> Thanks for all the ideas and peripheral info.
>
> 73,
>
> Fred ("Skip") K6DGW
> Sparks NV USA
> Washoe County DM09dn
>
>
>
> On 4/15/2017 10:40 AM, Clay Autery wrote:
>> I would think it would depend almost entirely on the orientation of the
>> tunnel... (and satellite reception azimuth).
>>
>> First, the longest of those two tunnels is only 425 feet or so. The
>> other is significantly shorter (southbound).
>> The tunnels are oriented generally north/south which is the preferred
>> direction IF you have to monitor geosynchronous satellite transmissions
>> from overhead... sort of).
>> You are right on the edge of a large body of water, which while not
>> brine, has better conductivity than the soil around the lake.
>> Significant potential for reflections off the high ground on almost all
>> sides....
>>
>> Don't know where that first tunnel is, so I can't comment. But if you
>> gotta hear in a tunnel.... those two would be great candidates...
>>
>> 73,
>>
>> ______________________
>> Clay Autery, KY5G
>> MONTAC Enterprises
>> (318) 518-1389
>>
>> On 4/14/2017 10:47 PM, Fred Jensen wrote:
>>> Semi-related curiosity regarding shielding. My wife's car has
>>> Sirius/XM radio. It usually loses contact with the satellite driving
>>> under Interstate bridges and the like. Likewise in the garage. OTOH,
>>> at our previous home there was a tunnel through a small hill, perhaps
>>> 1/4 mi long. The XM worked fine through it. There are a pair of
>>> tunnels at Cave Rock next to Lake Tahoe through a granite mountain.
>>> XM works fine through them too. Anyone know why?
>>>
>>> 73,
>>>
>>> Fred ("Skip") K6DGW
>>> Sparks NV USA
>>> Washoe County DM09dn
>> ______________________________________________________________
>> Elecraft mailing list
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Bob Nielsen-4

Re: KPA500 mobile?

In reply to this post by Clay Autery

Waveguide below cutoff.

On 4/15/17 10:54 AM, Clay Autery wrote:

> The ultimate directional, high-pass filter... <grin>
>
> ______________________
> Clay Autery, KY5G
> MONTAC Enterprises
> (318) 518-1389
>
> On 4/15/2017 10:14 AM, Jim Stahl via Elecraft wrote:
>> OTOH, this can be a feature of tunnels, not a bug. Several years ago I was riding on the “BikePike”, an abandoned section of the PA Turnpike east of Breezewood that has become a bicycle route featuring two old tunnels. Although closed off to motor vehicle traffic, we noticed a pickup parked outside the entrance to one of the tunnels. A few hundred yards into the tunnel we encountered a minivan with lots of high end electronic test equipment. Turns out the guys were doing tests on some military equipment, to determine that it was RF quiet to prevent detection by enemy forces. We didn’t ask a lot more, lest they would have had to shoot us :-)
>>
>>
>> 73 - Jim K8MR
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Clay Autery

Re: OT: Re: KPA500 mobile?

In reply to this post by k6dgw

The tunnel on Taylor Road, Newcastle, CA, which is the best candidate
for a tunnel on a road that may have been part of the old US Route
40.... as it officially ends in Utah now. :)

That tunnel runs ENE to WSW or therabouts...

0.103 km or 544.6 feet....
62 degrees 49 minutes from south to north....

Seems off axis unless the satellite is way off-axis.... but I had to use
a seriously off-axis sat once when I lived in CA.... Had to aim the
dish almost due east near the horizon...

We just renewed for her for another 3 years... She's happy, I'm happy.

Waveguide.... I don't know enough to hazard a guess.... But at a an
approx 13 centimeter wavelength, sat sigs can certainly travel down a
large tunnel if it enters at a small enough angle of incidence....

AND, maybe that water is helping contain the signal in the "guide".

#5.... cool to know.

73,

______________________
Clay Autery, KY5G
MONTAC Enterprises
(318) 518-1389

On 4/15/2017 6:32 PM, Fred Jensen wrote:

Clay Autery

Re: KPA500 mobile?

In reply to this post by Bob Nielsen-4

Touche! :)

______________________
Clay Autery, KY5G
MONTAC Enterprises
(318) 518-1389

On 4/15/2017 7:24 PM, Bob Nielsen wrote:
> Waveguide below cutoff.
>
> On 4/15/17 10:54 AM, Clay Autery wrote:
>> The ultimate directional, high-pass filter... <grin>
>>
>> ______________________
>> Clay Autery, KY5G
>> MONTAC Enterprises
>> (318) 518-1389
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Dan Baker

Re: KPA500 mobile?

In reply to this post by Mike Smith VE9AA

The very best station on Sirius/XM really destroys the beautiful melodious
sounds and overtones coming from the banjo. It gives it a watery metal
sound. However that does not stop me from listening to it. It is really all
about the content. That's why I can enjoy bluegrass on my iphone or XM
radio. Nothing coming close to listening live music when you are surrounded
by other pickers. So you do not have to bother with finding the perfect
speaker or stereo. They can never reproduce what you hear live. Same thing
with radio. It is all about the content. This is one reason we enjoy CW so
much. The tone sounds like you are in presence of the sending cw operator
coming out of our receivers. It only has to reproduce one tone, it's fairly
narrow and it sounds live. Jim K9YC I am sure you have good term for this.
I don't know what the phenomena is called. Maybe if the speaker was shaped
like a banjo that would be a good place to start to reproduce its sound
however, then you need another one shaped like a dobro and so on. Not
really practical.

73, Dan KM6CQ

*Don't sacrifice your hobby for the right house.*

I occasionally car pool to ham events with a neighbor in his high end
VW. He bought the satellite service, and we sometimes listen to it. It
drops out with foliage and under overpasses. Sound quality is so bad
that it's hard to listen to any form of acoustic music. Perhaps too much
data compression, made worse by any problems with the signal path.

73, Jim K9YC
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