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Dish Network

Dish Network and DirecTV trade suits over ad claims
Dish Network Corp, the No. 2 U.S. satellite television operator, counter sued DirecTV Group for running false and misleading advertisements, a month after its rival charged the company over similar claims, court documents showed.

Dish Network Satellite TV Vs. Cable TV - Which is Best?

DISH Network Satellite TV vs. Cable TV

DISH Network has been in a heated battle with U.S. cable companies for a number of years to get your business. While Network has been gaining customers most cable companies have been losing their customers to DISH Network. Here's why ...

DISH Network Satellite TV vs. Cable TV Fees

Cable TV fees vary from region to region, but the average monthly cable subscription fee is $39.95. In my neck of the woods the base fee is $37.30 a month for 64 channels, plus $10.95 a month if I were to add some digital channels.

DISH Network's subscription fees start at $19.99 for 40 channels, and $29.99 for 230 channels including 60 Sirius radio channels. All DISH Network's programming is in digital format and you don't have to pay extra for it.

Cable TV fees have increased an average of 22% over the last three years while DISH Network's fees have remained the same.

DISH Network Satellite TV vs. Cable TV Equipment

When you subscribe to cable TV you are usually given free cable boxes but if you want a DVR (digital video recorder) receiver you'll have to pay for it.

With DISH Network you get a free satellite TV dish and a four-room receiver system for free, and DISH Network will give you a free DVR receiver or a free HD (high definition) receiver.

DISH Network Satellite TV vs. Cable TV Installation

Cable TV installation fees vary from region to region. Installation in my area costs $39.95 for one room and $9.95 for each additional room.

DISH Network will install an entire four-room satellite TV system free, and when your installer is done he or she will show you how to operate your system.

DISH Network Satellite TV vs. Cable TV Programming

When it comes to programming there's really no comparison. Even satellite TV rival DIRECTV can't compete with DISH Network's 350 channels, which includes 52 music channels, 60 Sirius satellite radio channels, 31 movies channels, 10 sports packages, 21 international channels, and 80 pay-per-view channels.

With cable TV you only get a few channels in digital format whereas all DISH Network programming is in digital format, giving you a much higher-quality picture and a more realistic sound. DISH Network also has the most HD programming.

DISH Network Satellite TV vs. Cable TV Reliability and Customer Service

Cable TV blackouts average 3% to 5% per year, while DISH Network's average is 1% per year. And DISH Network has ranked higher than any cable company in J.D. Power's customer satisfaction ratings for the last five years in a row.

In most parts of the country customer service is limited to regular business hours. DISH Network offers toll free and online customer service 24 hours a day, 7 days a week, 365 days a year.

Bottom Line

It's really a no brainer. When it comes to which service offers the most channels, the least expensive programming and installation fees, the best picture and sound, the highest reliability, and the best customer service, DISH Network is the clear winner.

Visit http://www.TheSatelliteTVGuide.com for more information, ordering information, plus the latest special offers from DISH Network. Click on this link for a side-by-side comparison of DIRECTV vs. DISH Network.

About the Author

Adapter Antenna Usb

adaptador wireless usb AND wireless connection: what's the difference?

I mean, I have a laptop which has its internal antennae for wireless connections... the ones we use have on internet caffes, hotels, airports etc.

But lately I've heard on internet using an adapter usb thing. What's the difference? Do I have to have a cable internet connected at home for getting usb internet connection? or what?

Please, don't use techy term!

, you know,

a USB wifi adapter is a small device that you can plug into a computer and use it to pick up wireless signals in the area(like ones at starbucks and panera bread and home networks). if you have a wireless card in your laptop you dont need one. if you want to use it in your house you will need to use a wireless router. its a small box with 1+ antenna(s) that you plug into you cable or DSL modem and it sends a wireless signal through your house that you can pick up with your wireless card or USB wifi adapter. i hope that answers your question

High Gain

which are good high-calorie supplement for weight gain?

I wannna gain weight. I was wondering if you know any tried and tested high-calorie weight gain supplement. I am already taking lots of protein powder. Please suggest. Thanks in advance.

drink Ginseng tea

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Power Amplifier System for High-Power, Passively Q-switched Micro laser

I. INTRODUCTION

Passively Q-switched microchip lasers are simple, compact and reliable sources of high repetition rate (1 to 100 kHz), near-infrared, sub-nanosecond pulses. To date, low-energy (0.3 to 3 mJ/pulse) and mid-energy (30 to 180 mJ/pulse) microchip lasers have been reported [1] with pulse durations of 200 to 500 ps and 650 to 2000 ps, respectively. For some applications, for instance, high precision ranging and imaging, higher-energy pulses, up to 360-440 mJ/pulse [2, 3] are required with pulse durations approaching 200 ps. The pathway to higher pulse energies requires the use of higher saturable absorption, which inevitably leads to longer pulse durations. An alternative approach is the use of a MOPA design with a microlaser oscillator and multipass amplifier [3]. In the only reported work to date on this approach, a MOPA system operated in the 10-m J range, producing 500-ps pulses [4].

We present here a MOPA system generating 335 m J at 1064 nm with efficient harmonic conversion to the visible and UV. At all wavelengths, the pulse durations were <400 ps. This source is a valuable tool for applications that include ranging, LIDAR, micro-materials processing, and UV spectroscopy in chemistry and biochemistry.

II. SYSTEM DESCRIPTION AND EXPERIMENTAL RESULTS

                Figure 1 shows a schematic layout of our MOPA system. A 1-watt, fiber-coupled diode laser operated at a 2 kHz pulse rate is used as a pump source for the Cr:YAG passively Q-

switched Nd:YAG microlaser. Pump light emerging from the 100-m m, 0.22 NA fiber is collected and focused into the microchip using two AR-coated aspheric lenses. The fiber is

positioned at the front focal plane of the first lens, and the microchip at the nominal back focal plane of the second lens. Two different "telescopes" were used to optimize the microlaser output: a 4:3 or a 2:1 reducing telescope. Approximately 98&percnt; of the light emerging from the fiber is delivered to the microchip when using either telescope.

The microchip laser output is collected by a spherical 50-mm FL lens. This lens is typically positioned about 63 mm from the microchip so the beam is gradually focused into the amplifier stage. The beam then passes through a TGG Faraday isolator equipped with input and output Glan-laser polarizers.

A half-wave plate positioned before the collimator lens adjusts the polarization angle of the microchip beam as it enters the first polarizer of the isolator. A second half-wave plate adjusts the polarization angle of the beam emerging from the second polarizer. The beam is turned 90° by the first 45° -incidence HR (45 HR), goes through a +150 mm FL cylindrical lens that focuses in the vertical plane, and bounces off the second 45 HR, before entering the 3-pass amplifier stage.

The cylindrical lens is positioned about 150 mm from the center of the amplifier slab, taking into account the fact that the beam makes three passes through the slab (the separation between the slab assembly’s miniature fold mirrors is about 20 mm, and the slab is about 15 mm long). The beam is back-reflected through the amplifier with a flat HR , and makes another 3 passes through the amplifier slab.

The back-reflected, double-pass amplified beam passes back through the optical system and into the Faraday isolator. The plane of polarization at the first polarizer is now rotated 90° relative to the microchip laser polarization. The double-pass-amplified beam is coupled out the system at the first polarizer, and emerges with a polarization vertical to the plane of the paper.

 

 

Fig. 1. Schematic layout of the Microlaser-Amplifier system.

Our amplifier gain material, Nd:YVO4, is particularly well suited for amplifying pulses with energies below 100 m J because of its extremely high gain. This is demonstrated by Fig. 2, where we present calculated double-pass gain curves for cw-pumped multi-pass slab amplifiers based on different Nd-doped materials.

The amplifier design employs a slab-geometry gain module with transverse pumping. The gain module consists of an a-axis-cut, 2-mm high by 3-mm wide by 15-mm long Nd:YVO4 slab. The slab was cw side-pumped by two 20-W diode laser bars emitting at 808 nm, with top and bottom heatsinking. The side faces of the slab are polished and antireflection coated at 808 nm for maximum coupling of the pump light. The outputs of the diode laser arrays are collimated, in the highly diverging direction, by a drawn aspheric cylinder lens to produce a nearly rectangular excitation region in the laser crystal. The laser mode is passed three times through the length of the excitation region, using a pair of miniature external mirrors, essentially transverse to the pump beam. This design allows for efficient extraction of the stored energy in a TEM00-mode beam.

 

Fig. 2. Calculated double-pass gain curves for cw-pumped Nd-doped multi-pass slab amplifiers.

Three different monolithic microchip oscillator designs were evaluated, each having a different Cr:YAG layer thickness. The first two designs were made by Synoptics according to Q-Peak specifications. Both employ a 0.5 mm thick layer of 3&percnt;-doped Nd:YAG. One chip design has a 0.25-mm-thick layer of Cr:YAG with a nominal unsaturated absorption of 6 cm-1. The output facet of the chip is coated for 80&percnt;R. The other chip design is the same, except that the Cr:YAG layer thickness is 0.5 mm. Originally, we intended to try a similar third design, but with a 0.75 mm Cr:YAG layer and a 60&percnt;R output facet. However, this chip was not coated properly and was replaced with an off-the-shelf chip designed by Synoptics, which had features close to what we desired. This chip has a 1.25 mm layer of 1.9&percnt;-doped Nd:YAG, a 0.75-mm layer of Cr:YAG (6 cm-1), and an 80&percnt;R output facet. The pulse durations calculated for the three designs were 304, 204 and 200 ps, respectively. We believe that pump-light-induced bleaching is one of the reasons for increasing pulse durations [5].

The 0.75-mm Cr:YAG microlaser was used to construct the oscillator - double-pass-amplifier system. The microchip laser was quasi-cw pumped with a 1.1-watt peak-power pulse, at a 2 kHz pulse rate. The width of the diode pump pulse was adjusted to ensure single-pulse oscillation even when the double-pass amplifier was on. A typical oscilloscope trace of the oscillator pulses is shown in Fig. 3.

With 6.4 mW of microchip laser power, double-pass amplifier power was about 670 mW at an amplifier current of 31A. The beam quality of the double-pass-amplified beam was measured (by the Spiricon M2 meter) using the "90/10 knife-edge" method. M2 in the horizontal and vertical planes was measured to be 1.38 and 1.28, respectively. The pulse durations decreased to 370 ps as compared to ~ 440-ps from the microlaser.

 

 

Fig. 3. Oscilloscope trace of 440-ps oscillator pulse.

 

 

 

 

 

Table 1. Microlaser characteristics.

Microlaser parameters

Microlaser # 1, 4:3 telescope

Microlaser # 2, 2:1 telescope

Microlaser # 3, 4:3 telescope

Average power, mW

4.4

3.1

6.4

Pulse energy, m J

2.2

1.55

3.2

Pulse width, FWHM, measured, ps

700

400-440

400-440

Delay, m sec

90

40

70

Pump pulse width, m sec

120

60

120

Jitter, ns

± 100

± 100

± 100

Drift, 5 min, ns

± 300

± 200

± 200

We have also conducted experiments on nonlinear conversion of the amplifier beam. For second harmonic generation (SHG) we used a non-critically-phase-matched, Type I LBO crystal, with dimensions of 3 x 3 x 15 mm, mounted in a 1700 C, temperature-stabilized oven. Third harmonic generation (THG) at 355 nm was accomplished with a room-temperature, 3 x 3 x 12 mm, Type II critically-phase-matched LBO crystal (q = 42.7° , f = 90° ). And, finally, for fourth harmonic generation (4HG) at 266 nm, a Type I critically-phase-matched, room-temperature BBO crystal (q = 47.6° , f = 0° ), 3 x 3 x 7 mm crystal was used. The beams were separated using a Pellin-Broca prism. At input power of 670 mW, the output power of SHG, THG and 4HG was 400, 240 and 86 mW, respectively, which corresponds to ~ 60&percnt;, 36&percnt;, and 13&percnt; conversion efficiency.

III. CONCLUSION

We have designed and constructed a highly efficient diode-pumped, short-pulse, energetic, compact and reliable microlaser-amplifier system. This design approach, we believe, will allow us to achieve even shorter (~ 200 ps) and higher-energy pulses, increase the conversion efficiencies of harmonic generation, and improve the compactness of the system.

 

 

 

 

REFERENCES

1. J. J. Zayhowski, "Passively Q-switched microchip lasers and applications," Rev. Laser Eng., v. 26, pp. 841-846 (2008).

2. J. J. Zayhowski, C. Dill III, C. Cook, J. L. Daneu," Mid- and high-power passively Q-switched microchip lasers," in OSA Trends in Optics and Photonics on Advanced Solid-State Lasers, v. 26, M. M. Fejer, H. Injean, and U. Keller (eds), (Optical Society of America, Washington DC, 2007) pp. 178-186.

3. J. J. Degnan, "Optimal design of passively Q-switched microlaser transmitters for satellite laser ranging," in Proceeding of 10-th International Workshop on Laser Ranging, Shanghai, PRC, 2006, pp. 334-343.

F. Druon, F. Balembois, P. Georges, A. Brun, "Compact high-repetition-rate pulsed UV sources using diode-pumped microchip laser and multipass amplifier," in Advanced Solid-State Lasers, OSA Technical Digest (Optical Society of America, Washington DC, 2008), pp. 329-331.

M. A. Jaspan, J. A. Russell, D. Welford, "Degradation of passively Q-switched microlaser performance due to pump-light induced bleaching of the saturable absorber," to be submitted to Opt. Letters.

 

 

About the Author

Assistant professor in lord venkateswara engineering college.I am doing phd in sathyabama university, Tamil Nadu,India.

Gain Antenna

What is antenna directional gain?

The antenna gain is not an absolute , it is measured in a certain direction and is the result of dividing the assembled power of the anteena in that direction by an the assemble dpower of the anttena in the same direction if it is an omni directional one , sorry but i forgot the formula for the phenomena

Radio Antenna

'Smart' Contact Lens with Embedded Wireless Sensor Promises Earlier Diagnosis and Optimized Treatment of Glaucoma
STMicroelectronics , the world's leading supplier of MEMS devices for consumer and portable applications, has announced that it will develop and supply a wireless MEMS sensor that acts as a transducer, antenna and mechanical support for additional read-out electronics in a breakthrough platform developed by Swiss company Sensimed AG.

Satellite Radio Antenna Connector

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About the Author

Satellite Direct Tv Scam