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TelePost Inc (LP-700) - Digital Station Monitor, Digital Power/SWR Meter, Waveform Monitor Scope and Modulation Spectrum Display, 7in Color TFT Display, Touchscreen/Physical Controls, USB Interface, 12VDC/800 mA Max, Black

Description:

The TelePost Inc LP-700 Digital Station Monitor: Digital Power /SWR Meter, Waveform Monitor Scope and Modulation Spectrum Display all in one convenient package.

What is LP-700?

LP-700 is a digital station monitor which displays detailed information about the transmitted signal of a station. It displays the sampled signals in numerous formats including Power/SWR, various oscilloscope type displays and a spectrum display. The sampled signals are obtained by demodulating the RF, like in a traditional wattmeter, and should therefore work on any frequency for which there is a suitable directional coupler with the appropriate voltage scaling and time constants. It should be noted that demodulated samples are audio frequency based and not the same as RF samples. With some types of modulation, the demodulated audio is not a linear representation of the modulation signals, therefore the spectrum display works quite differently than a true spectrum analyzer. This doesn't pose a problem for AM signals, where the demodulated audio is faithful to the modulation signal, but is a challenge for SSB and other signals without a carrier. For this reason, we have developed special test signals which allow for some traditional SSB tests to be performed, although the tests cannot be directly compared to measurements from a true spectrum analyzer. In many cases, though, similar information can be gleaned from the tests, and they can be used for comparative tests to see the effect of changes to the transmitting equipment.

Features and Specifications:

• 7in Digital Station Monitor
• Bright 7in Color TFT Display w/800 x 480 Resolution
• LP-500 has a smaller enclosure and a 5in Display, otherwise the two meters are the same.
• 32-bit Main Processor
• Touchscreen controls of all functions, plus physical switches for the six main function keys
• Graphics and Audio coprocessors
• (8) 16-bit / 200 ksps ADCs with Adjustable Oversampling
• Low Distortion Proprietary Custom Digital Test Signals to Aid in Rig & Amplifier Adjustments using WFM and Spectrum Displays.
• Distinctive Aural/Visual Alarms for Each Channel for both Power and SWR.
• Native USB Interface - No Drivers Needed (not needed for normal operation)
• Flash Upgradeable
• Includes Windows based "VM" (Virtual Meter) software which allows computer control and monitoring of the LP-700 locally, or remotely using RDP or a USB Device Server.
• Fast Screen Refresh
• 12VDC Operation / 800 mA maximum.
• Interface to Rig is Through Remotable RF Couplers using CAT5/6 cable of any practical length.
• Provides Extensive Information About the Quality of Your Transmissions
• Size: LP-500: 9.125"W x 6.1"D x 4.88"H (23.2cm x 15.5cm x 12.4cm)
• Size: LP-700: 10.125"W x 6.1"D x 5.63"H (25.7cm x 15.5cm x 14.3cm)
  
• Watt / SWR Meter Features
• • Couplers for HF, VHF, UHF... Power up to 10KW (VHF / UHF available soon)
  • Up to 4 Couplers with Simultaneous Sampling & Auto-Ranging
  • NIST Traceable Calibration
  • Large Numerals for Power and SWR at a Glance
  • Simultaneous Bargraphs for Instantaneous
  • Peak Pwr, Average Pwr & SWR
  • "Sticky" bar displays highest peaks in all modes
  • Flexible Multi-Channel SWR & Power Alarms w/ Adjustable Set Points
  • SWR Protection Relay Jacks for 2 Amplifiers
  • Optical Encoder Adjusts Averaging Time (Fast, Medium, Slow)
• Waveform Monitor Scope Features
• • Full screen Waveform, Trapezoid & Scope Displays (Trapezoid requires two couplers)
  • Adjustable Sweep and Trigger with Memory
  • 5 Presets for SSB, CW, PSK plus 3 User Selections
  • 10 Vertical Scales per Channel with Memory
  • Multiple "Split-Screen" Displays with Combinations of Waveform, Power/SWR, Trapezoid and AM Modulation (w/ Bargraphs/Readouts for Positive & Negative Peaks)
  • Touch Screen Cursors for Measuring Time Intervals & Levels
  • Adjustable Peak Markers to Show Preset Power Limits
  • Freeze Button to Facilitate Touch Screen Measurements
  • Optical Encoder for Adjusting User Sweep Presets and Trapezoid Horizontal Gain (Width).
• Spectrum Display Features
• • Displays Modulation Spectrum of Transmitted Signal, as sampled by the coupler *
  • Adjustable Span & Averaging
  • Linear and Log Frequency Scales
  • 18 bits Effective Resolution
  • Up to 80 dB Measurement Range
  • Touch Screen Cursors for Measuring Frequencies & Levels
  • Adjustable Peak Level Marker

    *The Spectrum display does not sample RF directly, so results cannot be compared directly to an RF spectrum analyzer. Useful comparative measurements can be made, however. Because the couplers employ diode envelope detectors, signals without a carrier would normally be distorted during demodulation. To account for this, we provide special test signals for these modes which add subcarriers to simulate the existence of a carrier. See usage guidelines in the User Guide for more details.

    While the LP-100A couplers look similar to the LP-700 couplers, they are completely different and are therefore not compatible.

    Important notice for LP-100A owners: LP-700 will not replace the LP-100A. The LP-100A will continue with some important features not provided in the LP-700.

• Specifications:
  (With LPC-501 coupler.) Subject to change without notice.
  • General:
    • Model: LP-700
    • Power Range 0.1W to 3KW PEP (1500W Average)
    • Absolute Power Accuracy +/- 5% at 7 MHz, 10 to 1500W.
    • Flatness Better than +/- 3% from 1.8 to 54 MHz (+/- 1% typical from 1.8 to 30 MHz)
    • Directivity >30 dB, 1.8 to 54 MHz
    • Return Loss >30 dB, 1.8 to 54 MHz
    • SWR Range 1.00 to 9.99
    • SWR Accuracy ~5%
    • Bar Graph Resolution 600 steps for each range, Manual or Auto-Ranging
    • Number of Channel 8 simultaneous (FWD & REF power for 4 couplers)
    • Channel Balance +/- 0.1%
    • Memories Range & Alarm settings are saved per channel Channel settings are saved per mode
    • A/D Converter 16-bit / 200ksps, plus oversampling (2X to 16X).
    • DAC Resolution 18-bit, 96 dB SNR
    • Screen Refresh 5 Hz to 70 Hz, depending on mode, sweep/span settings.
    • Sampling Rate 2.5k to 80 ksps, depending on mode, sweep/span settings.
    • Display Resolution 800 x 480 pixels (WVGA)
    • Display Type TFT with White LED Backlight
    • Display Size LP-500: 5" Diagonal, LP700: 7" Diagonal
    • Test Tone Output 250 ohms, 350-500mVpp, unbalanced, 0.01% THD into 10K load
    • Power Requirements 12-16VDC @ 800 mA maximum
  • Scope:
    • Sweep Rate 1.0 to 20.0 ms/division in 0.1 ms steps Factory Presets and 3 User Adjustable Presets
    • Display Modes 7, including 4 split screens
    • Trigger Modes Normal, Plus, Minus, Plus/Minus, Free Running.
    • AM Modulation % 0 to 150, positive. 0 to 100 negative.
    • Cursors 2, measuring peak voltage and time (ms)
    • Markers 1 or 2, adjustable to show preset power limits
  • Spectrum:
    • Frequency Spans 2.5, 5.0 & 10.0 kHz, w/linear or log scaling
    • Span Multiplier 5X (500 & 1000 Hz, linear)
    • RBW 1 to 20 Hz, depending on span
    • Averaging 2X to 16X
    • Full Scale Reference +45, +55, +65 dBm
    • ADC Dynamic Range > 90 dB
    • Coupler Dynamic Range Up to 80 dB, depending on modulation type
    • Cursors 2, measuring peak power (dBm) and frequency (Hz)
    • Markers 1, adjustable to show preset power limit
• Additional Couplers:
  • LPC-502
  • • Range 5KW PEP / 2500W average
    • Flatness +/- 3% from 1.8 to 54 MHz (+/- 2% typical from 1.8 to 30 MHz)
    • Directivity > 30 dB for 1.8 to 54 MHz
    • Return Loss > 30 dB from 1.8 to 54 MHz
  • LPC-503
  • • Range 10KW PEP / 5KW Average
    • Flatness +/- 5% from 1.8 to 30 MHz (+/- 3% typical from 1.8 to 30 MHz)
    • Directivity >30dB from 1.8 to 30 MHz
    • Return Loss >30dB from 1.8 to 30 MHz
  • LPC-504
  • • Range 3KW PEP / 1.5KW Average
    • Flatness +/- 1% from 144 to 148 MHz
    • Directivity >30dB from 144 to 148 MHz
    • Return Loss >30dB from 144 to 148 MHz
      
  • Connections:
    

    Power: 12-16 VDC @ 800 mA maximum, center pin positive, 5.5mm OD / 2.5mm ID. The supplied cable either has a white stripe on the positive wire, or ridges on the negative wire, depending on the cable supplied. The meter has a protection diode to prevent damage in case of reverse polarity. The meter also has a built in replaceable 1A automotive type plugin fuse on the PCB for protection. We recommend a well regulated supply with a 1A to 1.5A rating. After much testing, we found an inexpensive linear (not switching) supply that is very clean. We offer these for sale for $15. An alternative is to use the accessory 12VDC jack on the rig if it can supply the current. You can also use a 12VDC power distribution strip like RigRunner connected to the main station DC supply. When sharing a power supply with the LP-700 and rig, make sure that the supply, rig and meter are all bonded together with heavy wire or copper braid. If there is any residual DC voltage on the ground lead to the meter, it can add noise to the scope displays and increase the power and SWR readings. Using a separate supply like the one mentioned above avoids the problem, but it's still a good idea to bond all your equipment together.

    PTT: For older amplifiers, loop the PTT (send, amp keying) between your amplifier and rig through the LP-700 using RCA cables. Two isolated pairs of connectors are provided for connecting two amplifiers. Use either pair for either amplifier.

    USB 2.0: Connects to computer using standard USB cable (Type A to Type B connectors). Used for flashing firmware and interfacing to LP-700 VM and future utility program. Can be connected to USB 2.0 or 3.0 jacks on PC. No special drivers are necessary since the standard Windows drivers are used. Windows should automatically recognize the LP-700 as USB HID (Human Interface Device).

    Couplers: Connect to corresponding jacks on the coupler(s) using supplied or user provided CAT5/6 shielded Ethernet cables. Unshielded (UTP) cables are probably acceptable as well. See Fig.1 on page 3.

    Test Tones: Audio output for built in test tones. 3.5mm mono. Connects to the MIC or LINE input of the rig. An attenuator will be needed in the case of mic input, and possibly galvanic isolation (transformer). Interfaces designed for a sound card based RTTY setup can work for this. To minimize ground potential differences between the meter, rig and power supplies, it is recommended that they all be bonded together with heavy wire or copper braid. This will minimize pickup of noise on the test signal displays.

    Line Level... Most rigs have a high Z (10K) line input designed for sound card based digital modes. These inputs work well for the LP-700 test tones. One some rigs they are labeled as line inputs, and have dedicated RCA or 1/8" (3.5mm) jacks. On some rigs they are part of an accessory jack or a DATA jack. These are generally DIN type connectors. Consult your user manual for specifics.

    Mic Level... There are some inexpensive "sound card" interfaces available to converting line level outputs to mic level rig inputs, with level adjustment and isolation. Devices in this category include the W2IHY iBox, RigBlaster Nomic ($60USD) and several interfaces from MFJ, like the MFJ-1273 and -1275 series. I have tested these and found that they can provide proper levels to the rig mic jack, and minimize the effects of multiple ground returns. These devices do not utilize magnetically shielded transformers, so it is important to not place them near power supplies with large transformers. We will be publishing a help file on the LP-700 web page detailing methods to avoid pickup of these signals. In the meantime, you can check out the discussion "clean up 2 tone signal" on the LP-700 User Group or extensive info published by Jim Brown, K9YC, http://audiosystemsgroup.com/HamInterfacing.pdf

    Creating your own test tones... In addition to the built in tones, you can create your own tones and save them to the microSD card inside the LP-700. The card uses the FAT16 file format, and the files must be named USER0001.wav through USER0004.wav. The wav format should be 16-bit, 44.1 kHz sampling rate. Remove the card and plug it into a PC to save the new files. It's located on the audio daughtercard near the test tone output jack. The files can be any valid wav file, including voice.

• Color: Black
• Manufacturer's Limited Warranty - 30 Day(s)
• Sold: Each

TelePost Inc (LP-700) - Digital Station Monitor - Above picture shows the relative sizes of the LP-500 and LP-700 in comparison with other familiar pieces of equipment at N8LP.

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