Telepost LP100a Digital Vector RF Wattmeter

LP-100A Features & Specs

For information directly from Larry the manufacturer at Telepost here is the URI
If you should decide that you “Really Need” one of these please when Ordering mention the fact that you saw the review here please.

  • Dual
    Coupler Option. Allows one LP-100A to use two couplers, with
    auto-sensing and switching to the active coupler.
    Great for SO2R operation or when your transmit paths are
    different for HF and 6m
  • Several new menus for additional customization of user preferences
  • LP-100A now integrated with N4PY Rig software
  • Graphic VFD display with high contrast non-glare neutral density filter
  • Front panel power switch
  • Large scrolling call sign screen saver
  • Setup screen for call sign entry
  • Setup screen for display brightness
  • Setup screen for screen saver timers
  • Dual 40MHz Processors
  • Per-band power calibration, user adjustable in 0.1% steps
  • Frequency counter – user adjustable
    per-band corrections of all parameters.
  • Only meter with Z, R, |X|, Phase display… not affected by local
    broadcast stations as antenna analyzers can be. Super wide autoranging power range
    of 50 mW to 3000W, 160-6m… perfect for QRPp through QRO
  • Optional couplers for 5KW and 10KW. Our 10KW will handle more power
    and generate much less heat than our competitor’s.
  • Only meter with Graphic VFD display. See Pictire below<
  • Only meter with simultaneous
    bargraphs for Power and SWR (or Power and Ref Pwr).
  • Highest bargraph resolution. 90 segments gives 1% tuning resolution
    with standard bargraph range settings (adjustable)
  • Only meter that has a “sticky” bar to graphically show peak hold
    point even while bargraph is moving.
  • Fast attack bargraph
    will accurately display a single “dit” at over 100 wpm. Decay
    adjustable for Fast, Med, Slow.
  • Active temperature compensation. Only other meter with this is Alpha.
  • True 12-bit A/D
    converter gives <1W resolution
    at 2000W. 13.6 bit effective resolution up to 360W.
  • Return Loss (RL) display of 0 to 49.9 dB with bargraph
  • Separate scale for dBm measurements, +15.0 dBm to +64.0 dBm with bargraph
  • Field Strength input covers the range of
    -15 dBm to +33 dBm (0.04 mW to 2W)… great for beam pattern and bench measurements
  • Peak to Average ratio
    screen. Allows accurate checking and setting of compression in your
    speech processor.
  • Support within TRX-Manager for direct remote monitoring
  • Call sign screen saver – user programmable
  • Free Plot program displays SWR, Z, Phase, R+jX (including sign), reflection coefficient,
    Return Loss and Smith chart.
  • SWR alarm with “snooze” mode for antenna tuning. Alarm has LED, PTT
    relay and audible sounder (which can be easily disabled)
  • G4HFQ’s free PolarPlot program works with the LP-100A’s Field
    Strength mode to provide automatic antenna pattern
    plotting. See software section of this web page.
  • Separate coupler with 50 ohm ports for uncluttered desktop – remotable
    up to 50′ with appropriate calibration.
  • Three autotanging scales with independently adjustable maximums.
  • SWR display resolution is .01
  • SWR error < .15  (5%) from about 100mW to 3000W, <.05 typical
  • Power accuracy is better than 5%
    at any frequency from ~1W
    to maximum, 3% typical with NIST traceable factory calibration
  • Power display is actual power delivered to the load ( Fwd minus Ref
    power) or traditional Fwd power.
  • SWR Alarm system with set points for Off, 1.5, 2.0. 2.5, 3.0 and user
    setting. Audible & visual alarm, with PTT loop-thru & adjustable power
  • Windows® freeware Virtual Control Panel for software
    control or remote control.
  • Built-in bootloader to allow for firmware upgrades to be
    downloaded and installed.
  • Conforms to FCC Part 15 A &
    B, ICAS and CE radiated emission
    limits, tested and verified by accredited lab
Telepost LP100a Digital Vector RF Wattmeter

Telepost LP100a Digital Vector RF Wattmeter

Optional couplers for ham use include:

  1. LPC1, 3KW PEP/CW**, 1.8 to 54 MHz
  2. LPC2 0.10W to 5KW CCS*, 1.8 to 30 MHz
  3. LPC4 0.10W to 5KW PEP/CW**, 1.8 to 54 MHz
  4. LPC5 0.20W to 10KW PEP/CW**, 1.8 to 30 MHz
  5. LP100A Showing the Station Callsign - MM0ZIF

    LP100A Showing the Station Callsign – MM0ZIF


I first came across these when on DXPedition to Tiree, and was very impressed, whilst initially I understood the basics of what it can do, I rapidly became aware of
whatelse it could do. Not only does it provide you with real time statistics, alarms and the like it offers the chance to monitor two outputs at the same time
although you do require the dual coupler option to do this. Potentially this could allow you to monitor the outputs from two transcievers to two antennas using a computer
to monitor both with the LP100a gives real time data allowing you the chance to create plots and smith charts giving phase angles, reactance plots and Standing wave ratios.

The LP100a also works with Bob Freeth, G4HFQ’d Polar Plot Application which gives you access to polar plots, beam patterns and Power output also.

Whilst not the cheapest peice of equipment to do this job, I’ve found it invaluable for checking cables. Making sure Phasing harnesses.and more, I would not be without it

Whilst all the software is directly downloadable from the Telepost website most of it is very intuitive, although I wish someone would do something
with the Windows 98 graphics of the Virtual Control Panel (which mirrors the front of the main unit, meaning that if you wished you could put the LP100a somewhere else entirely.
Obviously this would be a job for a serial to ethernet interface as Serial cables at any length suffer with many problems. VCP even allows you to change your Callsign Screensaver!

Its worth it alone for the Alarm functions telling you when your SWR is getting out of hand 🙂

Further to this the user group and support are excellent, have a look at the Yahoo Group

Leave a Comment

error: Content is protected !!
%d bloggers like this: