Red Mountain Radio LLC

07/15/2026

We recently documented the resilient IP STL architecture we use for Mountain Chill (KRKQ) in the Colorado mountains and I've had some discussions with others in radio facing resilience challenges.

Our system grew out of the realities of broadcasting from a studio in a mountain town, where intermittent Internet interruptions can affect both our studio and our mountaintop transmitter. Most recently, the system successfully rode through a brief Internet outage during the Gold Mountain Fire near Ouray.

Our approach combines forward error correction, interleaving, geographically distributed cluster nodes, multiple ISPs, and automatic failover. We've also open-sourced the software on GitHub.

Details, diagrams, source code, and the engineering write-up:

https://www.redmountainradio.com/audiorack-rsp.html

I'm curious how others are approaching resilience for IP-based STLs. What has worked well in your environments?

(Graphic rendered by AI from our original line drawing)

10/15/2025

Breaking the ADC Bottleneck

We're tackling one of the biggest constraints in digital signal processing, the information-rate bottleneck imposed by even the fastest analog-to-digital converters (ADCs).

By moving key DSP functions into the photonic domain, we are implementing True Time Delay (TTD). TTD is an essential function for correlation-based and ultra-wideband processing, enabling new approaches to secure wireless and fiber communications and signal protection.

This shift opens the door to new ultra-wideband wireless and fiber techniques where real-time information processing rates on the order of 10 Tb/s are feasible. Yes, that's more than two orders of magnitude beyond what's achievable with top-tier electronic ADC systems.

(Photo: part of our photonic True-Time-Delay transmitter/receiver pair setup in development.)

07/01/2024

Red Mountain Radio is turning 21 years old next week. In the lead up, we've been sharing some of the products that we've had the pleasure to design or assist with since our founding. Over those years we've had over 60 different clients across as many different industries, and there's hardly been a product design problem that we could not solve.

Before we hit the big 21, it's one final set of images of our lab. This is where we prototype, test, and improve our designs. While our competitors often prefer abstract work at their desktop or laptop screens, we excel in ferreting out design problems with the oscilloscope, spectrum analyzer, network analyzer, and soldering iron.

This is also our homage to the most useful tool in the lab, the trusty Red Mountain Radio chalk board. Tough or complicated designs all get the chalkboard treatment. That includes countless system level designs like this one (details redacted).

As good power supply and digital design are key to low noise analog and RF performance, we've also been called on to designed countless complete systems including digital and firmware components.

Here's to many more years getting our hands dirty in the lab and at the chalkboard.

06/26/2024

Red Mountain Radio will be 21 years old in July. In the lead up, we are sharing some of the products that we've had the pleasure to design or assist with since our founding.

For example, this is one of several of our patents for a design which uses RF over fiber to make geological radar measurements down-hole, thus avoiding the problems that occur when operating active electronics at extremely high down hole temperatures.

https://patents.google.com/patent/US7450053B2/en

06/22/2024

Red Mountain Radio will be 21 years old in July. In the lead up, we are sharing some of the products that we've had the pleasure to design or assist with since our founding.

For example, this is a (~2015) design for a Carnegie Mellon University transmit/receive wireless test bed. This is a two channel (low phase noise) up/down converter. This translates 2.4 to 6 GHz to and from base-band in-phase and quadrature signals. It included custom band-pass filtering and an automatic T/R switch as well.

06/20/2024

Red Mountain Radio will be 21 years old in July. In the lead up, we are sharing some of the products that we've had the pleasure to design or assist with since our founding.

For example, we did all of the engineering work required to get KRKQ in Telluride on the air at its 11,000 ft. Gray Head site.

We began at the construction permit stage with just a transmitter and antenna in place, adding a custom DJ assist system, and an Internet plus a duplicate private point-to-point studio-transmitter link (STL). We also designed our IP-based STL protocol to use triple ISP redundancy, interleaving, and forward error correction in order to handle routinely flaky Internet, especially in Telluride in 2011.

With the exception of installing a new antenna array (we called in climbers for that), we continue to do all engineering to this day.

06/10/2024

Red Mountain Radio will be 21 years old in July. In the lead up, we are sharing some of the products that we've had the pleasure to design or assist with since our founding. While many products that we work on are specialty small scale items, many are also large scale consumer products.

For example, we redesigned the antenna and antenna matching in this line of Fossil smartwatches. We replaced the inefficient off-the-shelf Bluetooth E-field chip antenna with a B-field loop antenna and slot radiator. The antennas were all fine tuned with an antenna matching network to ensure a proper match as dictated by model specific factors such as the face circumference.

This 44mm Neutra Gen 6 Hybrid smartwatch gives you up to 2 weeks of battery life depending on usage and features an always-on readout display so you can get your heart rate, message previews, weather and more at a glance. Interchangeable with all 22mm Fossil watch bands. The Fossil Smartwatches A...

06/05/2024

Red Mountain Radio will be 21 years old in July. In the lead up, we are sharing some of the products that we've had the pleasure to design or assist with since our founding. While many products we work on are specialty small scale items for industry or lab use and/or are still covered by recent NDAs, many are also large scale consumer products that we designed over a decade ago.

The Bogen Enhancer is an infrared (LED) wireless microphone designed for classrooms or other environments where either privacy requirements or a high density of RF signals make RF wireless impractical. The IR wireless signals are isolated between adjacent classrooms, conference halls, etc. by walls which form a natural barrier to the infrared optical signals.

On this product, we redesigned for the existing product line for increased range and better noise figure. We entirely redesigned the optical receiver front end. We used an FM sub-carrier on the optical carrier with pre-emphasis and audio compandering for a large increase in range and signal-to-noise ratio.

BCWR/2 BCIRS/BCWBT/ACCESSORYS

06/04/2024

Red Mountain Radio will be 21 years old in July. In the lead up, we are sharing some of the products that we've had the pleasure to design or assist with since our founding.

"The Flight Light Radio Controller is designed to provide pilots direct, unassisted air-to-ground control of power circuits. Pilots activate lights from the air with key clicks from a VHF AM aircraft band radio. The controller uses a high precision radio to prevent false triggering."

Red Mountain Radio designed the radio and control circuity as well as the circuit board used in this product. It is field programmable to a variety of FAA operating frequencies.

Heliport Radio Controller - HLRC

04/22/2024

Today, we'll look at using the Bessel Null method of precisely setting the deviation of a broadcast FM transmitter using only a known audio tone and a spectrum analyzer. This is an incredibly power procedure that everyone in broadcast engineering should know about.

Today, we'll look at using the Bessel Null method of precisely setting the deviation of a broadcast FM transmitter using only a known audio tone and a spectr...