TelePost LP-500 Digital Station Monitor!

The next new addition to the station will be the TelePost LP-500 Digital Station Monitor. A must have to ensure proper station operation.

TelePost LP-500 Digital Station Monitor
The next addition to the station

From the TelePost LP-500 Website:

What is LP-500?

The TelePost LP-500 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
  • Oscilloscope type display
  • 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. 


TelePost LP-500 rear panel
Business end of the LP-500
When you're linear, it shows!
So you know you’re perfectly linear!

To utilize this feature two couplers are required (per radio in my case). I plan to have both the 6300 and 6700 using input and output couplers configured like this:

TelePost LP-500 wiring diagram
Block diagram of LP-500 hook up

I’m looking forward to installing the TelePost LP-500 as soon as possible. There’s a waiting list, and I had to pass on my position in the list due to an unforeseen expense at the time of availability.

I can see on the TelePost website that regular shipping is back in full swing.

Back to the front

Author: K6HR

Licensed since 1994. Active on HF / VHF / UHF / Satellite.

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