lp-500 Archives - K6HR SDR Server 2024

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.

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.

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RF Hardware Upgrades

I’ve finalized plans for this years hardware upgrades. After some careful consideration I’ve assembled my final list of RF hardware upgrades. 2018 has been a very busy year, but I’m finally to the point where I can devote more time and energy to the hobby side of things. I’m in the process of writing up a list of what I need to get done. I work best when I have my work sketched out and I can work through everything in logical steps. I find it helps me keep track of the details and saves me from re-work related delays.

Flex 6700
Telepost LP-500
LG 32UD59-B 32″ UHD 4K monitor with Ergo 45-295-026 (Monitor Arm)
APC BX1500M UPS
HDD upgrade to 500GB SSD
High Capacity HEPA Filter
W6LVP RX Loop #2
Comet CHA-250B Vertical HF Antenna
Additional Grounding and Ferrite requirements

Flex 6700

I mentioned this earlier in the year. The 6700 was the first item added to what would become the final list of new hardware. I’m getting a great deal from Flex on a “Certified Pre-Owned” 6700. Yeah, it costs a bit more than what we’ve seen some used units sell for recently, but having Flex service is well worth it.

Telepost LP-500

I’m on the waiting list and steadily moving up in the ranks! I’m hoping the fact that I’ll need 4 RF couplers doesn’t complicate the order. Hopefully they’ll have enough on hand as I arrive at the top of the list.

LG 32UD59-B

Now that I’ve had the LG UHD 4K monitor for a while, I’ve decided I really like it. I like it enough to add a second one. Complete with identical Ergo Articulating Arm Mount. I have a thing about keeping things somewhat symmetrical . So I usually always purchase monitors in pairs. This additional 32″ monitor will serve as the primary display for the GeoChron Digital 4K. It’s stunning! Wait until you see it! It’s gonna be killer!

APC BX1500M

This will complete the back-up power requirements for the shack. As previously mentioned the existing APC will be re-tasked.

EVO 860 500GB SSD Upgrade

I’m upgrading the shack PC to Windows 10, and I’ve decided to use a larger capacity SDD for the system drive, and re-purpose the existing SSD’s to be used on the web server hardware.

High Capacity HEPA Filter

One of my main goals is to finally eliminate the dust problem. During the rack build I was able to remove a tremendous amount of dust. Likewise, during the upgrade install, I will take further action. The plan is to use an air compressor to loosen, and then collect the dust with the HEPA. Rather than attempt to loosen all the remaining dust at once, I plan to do it in installments to avoid getting choked, or the filter getting clogged etc.

Comet CHA-250B Vertical / W6LVP Loop

On the recommendation of Ron, WB6IAG, I am installing a Comet HF vertical. This antenna will add some flexibility to the station RX. I am also adding a second W6LVP Loop antenna, and putting it, and the existing loop, on rotators! How’s that for an RX improvement!

Finishing Touches!

RF Hardware Upgrades

Of course the new gear all needs to be tied into the ground bar, and have ferrite’s applied to both ends of all the new cables. Perhaps the last finishing touch with be the replacement of the ugly cardboard above the air conditioner in the window! I’ll cut a custom fit a plexi-glass insert to close up the window properly once and for all!

Last Minute Addition! Kenwood TH-D74A

The Kenwood TH-D74A is a D-STAR transceiver. It is packed with amazing features. And….it comes complete with a learning curve! I recently became interested in D-STAR after doing some research on its capabilities.

RF Hardware Upgrades — Kenwood TH-D74A D-STAR Transceiver

K6HR Contest Station Block Diagram

SO2R HF Contest Station Configuration

K6HR Block Diagram — K6HR HF Contest Station Block Diagram

Expert 1K-FA: At the Center of SO2R Ops

The Expert 1K-FA does all the antenna switching automatically. Fully automated, and carefully programmed, the 1K-FA greatly reduces the chance of user error. The K6HR Contest Station Block Diagram makes this SO2R setup a bit easier to understand.

The transceiver is a FlexRadio 6700 featuring two Spectral Capture Units. I utilize the two SCU’s as “two radios”, each with its own amplifier, tuner, and antenna. I designate ANT1 as the Mosley TA-33-JR-NW (for all HF bands 20 meters and above) and ANT2 as my 130ft Height Compromised HF Dipole for frequencies on 30 down thru 160 meters. Low SWR across all amateur bands!

The cool trick is the operator can move freely through the bands and operate at will via either radio. The 1K-FA’s foolproof switching ensures the TX radio will get the correct TX antenna every time. The second radio, in every case will be connected to the wideband RX loop antenna.

Data Driven via Flex USB

The Expert 1K-FA and the Palstar autotuners operate based on frequency data received from the radio. The 1K-FA and the AT-AUTO autotuners follow the radio in realtime as the operator changes frequency.

The operator only needs to turn the ‘tuning dial’ and press the PTT!

LP-500 Station Monitor

I have installed the LP-500 station monitor with 4 sensors. You could say it takes the guesswork out of getting good reports!

Leveraging the four sensors of the LP-500 Digital Station Monitor, I can ensure both amplifier channels are operating at full output, with the lowest SWR, and best linearity at all times.

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