Over 20 years ago, when I needed to do a frequency coordination for a wireless microphone system I fired up a DOS program—black screen with white characters—and hand-entered the existing frequencies, television station numbers, as well as the proposed frequencies one at a time. After some churning, a result was displayed and it was either added to the list of coordinated frequencies or rejected. This was also in the days when single-frequency wireless was the norm, and a limited number of frequencies were available.
With RF Guru, complete television databases can be brought in with a simple city, zip code, or lat/long lookup, popular brands and splits of wireless microphones can be dragged and dropped, desired quantities can be specified and then calculated in one step, and color-coded results show any potential conflicts among channels. If you're mixing brands of wireless on a production, coordinating a large number of wireless mics, intercoms, and in-ears, making sure your system is compatible with the venue next door, or touring nationally or internationally with wireless, this powerful product is a worthy and cost-effective means to relieve the headache of interference.
RF Guru's Key Features
RF Guru coordinates frequencies across a variety of wireless equipment, for a single venue or for multiple venues when touring. The Intermod Test calculates intermodulation among transmitters when you have an existing set of frequencies, highlights those with potential conflicts, and allows the user to change, add, or delete frequencies. The Maximizer starts with groups of wireless equipment by manufacturer, model, and frequency split, for which the user specifies the desired number of channels from each split. Using its database of all tunable frequencies for the particular equipment, RF Guru calculates a list of frequencies with the fewest potential conflicts, given local television stations and any other wireless nearby that has been entered in the Other Systems page.
The system designer can set varying levels of permissible intermodulation among the transmitters, which is especially useful when large systems are being coordinated or the RF environment is heavily crowded with television and other signals. The Test Level “slider” control ranges in 10 steps between More Frequencies and Less Intermod. Selectable calculation formulas consider two and three transmitter interactions with 3rd and 5th order modulations. Color coding of each frequency in the list shows potential conflicts, and details are provided so the user knows how best to deploy the frequencies.
Each frequency can be named by function, channel number, user, transmitter type, and other characteristics. If the same basic setup will be used across multiple venues, the system designer can copy the information from the first venue into another venue, add the local television stations, and calculate the best set of frequencies for the new venue. Once the system is coordinated, RF Guru has a number of preset reports that can be generated for the tour log, and several formats for Avery labels so that each transmitter and receiver can be easily identified with the necessary information. Reports can be customized with the Report Designer.
An internal television database provides detailed information about TV signals within range of the venue, with complete and updated files for the U.S., Canada, and Australia, and channel information for most countries in the world. A dropdown menu is used to select the country where the venue is located, and when a TV channel number is entered RF Guru looks up the relevant broadcast specifications.
Getting Around in RF Guru
The first action in RF Guru is to set up a Production, which can be a single event or venue in a particular location, or a multi-venue national or international tour. The production is given a name and other details as desired. Once it has been created, the next step is to create a venue, which is a specific facility where the wireless equipment will be used. A Date From and Date To set of fields is presented, with a dropdown calendar, along with a Description field for additional notes.
Clicking Next takes you to a dialog where you select the basic action for the program to accomplish, either Intermod Test or RF Guru Maximizer. The intermod test is mainly for existing systems where the user wants to confirm that the selected frequencies will work together. The Maximizer is especially designed for building new systems and choosing the best frequencies available from that equipment, given the number of channels you need and the RF environment.
As part of this process, an option is given to look up the television broadcast stations in the vicinity. RF Guru has the ability to perform that lookup by city, zip code, or latitude/longitude coordinates. Enter the location by any of these means, select a desired radius in miles from the venue, then click Finish. All relevant TV stations will be brought into the program, including their channel number and call sign, bandwidth, power, distance from the venue, and type of service—digital or analog.
The next step is to click on the My System tab, and begin detailing the system you are using. Several brands of wireless microphones and other equipment are already loaded into the software—with detail by model, RF band split, frequency range, and a drop-down of all the frequencies to which each unit can be tuned within the band. If the brand or model you are using is not currently in RF Guru, click the Build A Custom Model button and input the manufacturer and model, band, power, and other details; all of the frequencies the particular wireless can tune to can be added either by formula or by inputting a list.
Select how many channels of each wireless split and type of device you need (for example, six channels of wireless mics in band A, six in band B, four in band C, two channels for in-ear monitors, and four channels for wireless intercom). Include your spare or backup channels as well. Once you have completed selecting the equipment and number of channels required, press Click to Start Maximizer and a series of intermod calculations will be done to select the best set of compatible channels for the particular venue, given the TV stations in the area and other wireless channels in locations near the venue that you have identified and input. They are shown on the Results page.
Intermodulation Results
If the television environment is not overwhelming (such as it may be in a major city), a moderate number of wireless channels are being used, and the equipment you are using covers a wide enough bandwidth, the Results page will likely show a list of selected frequencies with a light green background designating that there were no calculated intermod conflicts. Each row presents the frequency, channel designation, brand/model, and other details for that channel. Set your transmitters and receivers to these frequencies and they should all work together without interference or conflicts with TV broadcasts.
If an intermod conflict is calculated, the particular rows with the affected frequencies will have a light red background, and when you click on one, it and any other frequencies in the list that are related will turn dark red. A plus sign on the row can be clicked on to see details of the conflict. Knowing about potential intermod conflicts among channels gives you the information to make decisions, such as choosing to use fewer channels in a particular band and more in another, designating one of the frequencies causing a conflict as a spare, or making sure those particular frequencies are used on different sides of the stage so that the transmitters do not interact with each other as strongly.
RF Guru on Tour
If the same basic wireless system will be used from venue to venue, such as a tour where the performers are assigned certain wireless transmitters, along with in-ear monitors and wireless intercoms for the techs, RF Guru presents the opportunity to build the system for the first venue—and then to copy it into subsequent venues. With each new venue, the user has the opportunity to add the television stations for that location, enter the date of the event, and add other notes and details. Running the Maximizer for the new venues will highlight any frequency changes you'll need to make before the next show.
If you know of other wireless systems that may be in use in the venue or nearby, their frequencies can be entered into Other Systems. If venues are adjacent (such as in a theater district), an in-house wireless system will be in use along with what you're bringing in, or the camera crews or the media will be using various wireless devices, placing that information into RF Guru will allow the potential interactions between their frequencies and yours to be examined.
When the need for an additional wireless channel arises, just click the “I Need a Frequency” button. A dialog opens that allows the user to select which wireless hardware will be used to add the frequency, and the available frequencies within that unit will be calculated for potential intermod. The best candidate with the fewest intermod conflicts will be added to the Results list.
Continual Updates
The television databases are updated daily, and RF Guru continually pursues detailed television information by specific location for countries worldwide. New wireless models and manufacturers are added regularly, whenever the manufacturer provides them the detailed information. RF Guru is part of a suite of software products, which includes a comprehensive Show Builder; integration among the products is part of the development activities of the company.
Applications and Pricing
While frequency-agile wireless with scanning features and pre-coordinated frequency groups has been a great boon to audio engineers, it is not always sufficient. With a moderate number of systems across several splits, and taking steps to avoid the local television channels, these systems can do a great job of self-coordinating.
However, when your system consists of different manufacturers' wireless, when you have many channels operating simultaneously, when you are working in venues with existing wireless, when you need to consider the wireless mics' interactions with in-ear monitors and wireless intercom, or when you're touring from venue to venue and need to pre-plan and modify the wireless systems to take local television and other factors into account, RF Guru will be a great help—saving considerable time and troubleshooting for a minimal up-front investment.
The initial purchase price for a license of RF Guru is $79, which includes the first year of database updates and new features. After the first year, an annual $39 fee keeps the updates current—although the software will keep working in its current version without the annual payment.
