The Palomar Amateur Radio Club STEMLab
The PARC repeater site is situated 5600 feet up on Palomar Mountain. This provides a wide-ranging view, particularly west and south, of southern California away from big-city interference.
The STEMLab's purpose is to provide the community with access to resources that leverage these unique features of the PARC site for education and experimentation.
Use of the STEMLab is free to anyone with internet access subject to the availability of its resources.
What Is the STEMLab?
The Lab features multiple Software Defined Radios (SDR) that are accessible to its users over the internet. These provide signal data that can be used for demonstrations, learning exercises and experimentation.
The Lab offers a unique capability by providing access to HF, VHF and UHF signals with multiple SDRs capable of serving multiple users from anywhere there is internet access.
This equipment is meant to facilitate STEM awareness, education and training for members and the greater San Diego area community.
Educational material is available online for members, schools and the general public.
How the STEMLab Came To Be
The STEMLab was built by PARC member volunteers as a part of the 2022/2023 PARC Modernization Project. That effort is still ongoing and is expected to continue for some time to come.
ⓘ About the PARC 2022/23 Modernization Project
The STEMLab included two "Lab Benches".
- The HF Bench is dedicated to the HF radio bands.
- The Experimentation Bench provides access to the VHF and UHF radio bands.
STEMLab HF Bench
The HF Bench's two Airspy HF+ Discovery SDRs are accessed via OpenWebRX+ which is an SDR server application with a client that runs entirely in the user's web browser. No additional software needs to be installed to use the OpenWebRX+ client.
The KiwiSDR is accessed through its internal OpenWebRX server.
Users can explore the communications happening throughout the HF bands. The KiwiSDR supports many digital data and voice modes.
To access these SDRs, simply click on one of the Available buttons in the table to the right. (Note: if the label says Unavailable or More Info then the SDR is currently offline.
Below are links to information on how to use the SDRs. If you are unfamiliar with the applications these will help get you started.
ⓘ STEMLab HF Bench General Information
ⓘ OpenWebRX+ Information and Operation
ⓘ KiwiSDR Information and Operation
STEM HF Bench SDRS
| Amateur Radio HF Band SDRs | ||
|---|---|---|
| Band Coverage | Software Defined Radio | Click Available SDR |
| Amateur bands (10,12,15,17,20,40,80 meters) | Airspy HF+ Discovery #1 | |
| Amateur bands (10,12,15,17,20,40,80 meters) | Airspy HF+ Discovery #2 | |
| HF Band (~10 KHz - 30 MHz) | KiwiSDR v2 | |
Note: the SDRs are connected to Raspberry Pi devices running OpenWebRX+ SDR software.
The JYR8010-150W End Fed Half Wave Antenna is shared with both Airspy HF+ Discovery SDRs and the KiwiSDRv2.
STEMLab Experimentation Bench
The STEMLab Experimentation Bench SDRs access the VHF and UHF bands. The Experimentation Bench is intended more for providing access to various applications and data for education and experimental purposes. At the moment its SDRs are accessible through OpenWebRX+ servers like the HF Bench. But these provide man interesting topics to explore from aeronautical data links to amateur radio repeaters.
To access these SDRs, simply click on one of the Available buttons in the table to the right. (Note: if the label says Unavailable or More Info then the SDR is currently offline.
Below are links to information on how to use the SDRs. If you are unfamiliar with the applications these will help get you started.
ⓘ STEMLab Experimentation Bench Information
ⓘ PARC STEMLab SDRs
ⓘ A Brief Introduction to Software Defined Radio (SDR)
STEM Experimentation Bench SDRS
| STEM Experimentation Bench SDRs | ||
|---|---|---|
| Frequency Coverage | Software Defined Radio | Click Available SDR |
| 24.0 MHz - 1766 MHz | SDR #1 (RTL-SDR v3) | |
| 24.0 MHz - 1766 MHz | SDR #2 (RTL-SDR v4) | |
| 978 MHz UAT - 1090 MHz ADSB | FlightAware Pro Stick | |
Note: The SDRS are connected to Raspberry Pi devices running OpenWebRX+ SDR software.
The shared antenna is a Diamond D130NJ which covers approximately 25MHz to 1300MHz.
Note: As you navigate the site, you will see three types of links:
- The information links ⓘ indicate a page local to the site.
- The chain links 🔗 indicate navigation to an external site.
- The document links 📑 indicate a document download, like a PDF document.
Note: PARC does not sell or endorse any products mentioned in these pages.
Information is provided for education and instructional purposes only.