Frequently Asked Questions (FAQ)

Spectrotek Services designs and builds specialized RF-related electronic equipment, including signal processors, amplifiers, controllers, digital carrier generators, and related accessories. Many products are purpose-designed for experimental research applications, precision signal handling, and controlled waveform generation. We also provide documentation, schematics, and support materials for all major product lines.

Spectrotek equipment may be used for personal research, laboratory experimentation, educational projects, and technical hobby applications. While built to a high standard of electronic performance, our devices are not classified as commercial, medical or diagnostic equipment and are intended strictly for experimental and informational use.

No, we do not. Because most researchers want to use specific plasma tubes and may have other particular requirements for system configuration or operation, we only offer the essential components required for researchers to assembly a plasma tube system for there particular needs.

No, we do not. The manufacture of a high quality plasma tube (which is essentially just a high power Neon tube) is a specialized and complex process, requiring highly skilled technicians. We suggest using plasma tubes manufactured by Bill Cheb in Canada. Their web site is at https://billsplasmatubes.com. Our equipment is designed to give the best performance with Bill's plasma tubes.

Detailed product information, specifications, schematics, and application notes are provided on the individual product pages within this web site. Use the navigation links on the left side of the main site to select the product or topic of interest.

Contact details, including e-mail and other relevant information, are listed on the Contact page of this web site. Please include the product name and any relevant details when asking a technical question.

Yes, we do. Our YouTube channel contains instructional videos about our products as well as useful technical information. You can find our videos at https://www.youtube.com/@spectrotekservices.

Most products are simple to set up, but users should have a basic understanding of electronics, audio sources, and safe handling of powered equipment. Advanced units—such as signal processors and power amplifiers—may require some familiarity with power supplies, wiring and proper cable connections. Reading the product page and documentation before operation is strongly recommended.

Yes! It is entirely possible, and quite a few experimenters and researchers have built units with out parts kits, and some have even constructed their equipment as a one-off project by reading the information contained in the instruction manuals for our equipment. There are several pictures of such home-built units in the "Customer Photos" page on this web site. We encourage such construction activity, as it can save money and help them learn about the equipment in depth.

Each product page on this website includes detailed descriptions, feature notes, operational instructions, and any available schematics or downloadable documents. If you need additional clarification or cannot locate specific information, Spectrotek may be contacted directly for assistance.

We can supply some parts, however, items such as transistors, coaxial cable and other small parts are changing in price so frequently that we are unable to maintain stock of such items and offer them to our customers at reasonable prices. Most of these items re readily available from commercial electronic parts suppliers such as DigiKey, Mouser, Arrow, Newark, RS Electronics. Other miscellaneous items and coaxial cable are available on eBay and other second source outlets If you need a replacement for a specific product, please include the model name and a brief description or photo of the part.

Ordering is done by contacting Spectrotek directly using the information provided on the Order Information page. Some products may require configuration details before purchase, ensuring you receive the correct version or options. You will receive ordering instructions, pricing, and delivery estimates after contacting us.

Custom variations are sometimes possible depending on component availability, required changes, and technical feasibility. Requests for modifications should include details about your intended use, preferred features, and any required electrical specifications.

International shipping is available to most countries. Please note that we will not ship kits internationally due to customs problems. Delivery times depend on destination, customs processing, carrier availability, and local postal systems. Once shipped, you will receive tracking information (if available for your region). Customs duties, taxes, or handling fees are the responsibility of the recipient.

Shipping cost is based on package weight, size, and destination. We choose the most practical and cost-effective carrier for your location. Packaging materials and handling are included in the overall shipping total.

If your order does not arrive within the estimated time frame, or if it arrives damaged, please contact Spectrotek with your tracking information and order details. We will assist in initiating a claim with the carrier and determine what replacement or corrective steps may be needed.

Spectrotek products are warranted against defects in materials and workmanship for a period of one year after purchase. If a unit fails under normal use due to a manufacturing issue, it will be repaired or replaced at no charge. Warranty does not cover misuse, accidental damage, or operation outside the specified limits. Please contact us for a return authorization before returning any unit for repair. When returning equipment, you pay the shipping cost to us, and we pay the return shipping to you.

Please contact Spectrotek with the product name, purchase date or invoice number (if available), and a description of the problem. If repair is needed, you will receive instructions for returning the item. Most issues can be corrected quickly, and many repairs are covered under warranty. Please contact us for a return authorization before returning any unit for repair. When returning equipment, you pay the shipping cost to us, and we pay the return shipping to you.

In many cases, yes. Some Spectrotek units have revised or updated circuitry, or improved components available in later versions. If your device is an earlier model, contact us to see whether an upgrade path exists and what benefits or compatibility changes it may provide.

Almost any clean audio-frequency source may be used, including computers, sound cards, MP3 players, CD/DVD players, smartphones, tablets, and dedicated waveform generators. The essential requirement is that the source must be able to produce a stable, undistorted audio waveform at a sufficient voltage level to modulate or drive the connected Spectrotek device properly.

Most Spectrotek controllers and processors operate correctly when supplied with a peak audio voltage between approximately 2.0 and 5.0 volts. Signals below this range may not modulate reliably, while excessive input levels can cause clipping or internal limiting. Each product page specifies the ideal range for that model, and users should verify that their source device can deliver adequate output.

Yes. These consumer-grade devices may be used, provided they can deliver an adequate signal level and are not restricted by internal volume limiting or digital compression. For best results, set the device to maximum or near-maximum volume and avoid formats that introduce distortion, such as heavily compressed audio files.

Many modern computer sound systems employ internal DSP, volume normalization, frequency equalization or frequency roll off, power management, or filtering that alters the output waveform. Some laptops reduce output amplitude to protect small internal speakers, resulting in insufficient modulation voltage. In addition, low-cost USB sound cards may produce significant noise or distortion. For critical operation, a high-quality external USB audio interface or a dedicated audio generator is recommended.

Carrier frequency: The basic RF carrier frequency signal that is controlled or generated by the Spectrotek device. This usually either 3.10 or 3.30 MHz.

Modulation frequency: The audio signal that shapes or modulates the carrier output.

Sweep mode: A function that automatically varies the modulation frequency across a range, which is useful for scanning or experimental applications.

Understanding these distinctions is important because some devices support analog audio or digital modulation modes, frequency multiplication of the modulation frequency signal (e.g., 2× modulation frequency), depending on the hardware configuration.

Use good-quality audio cables for all low-level connections. Use shielded cables is available, although in most cases, shielded cables are not absolutely necessary. For high-level output connections (such as those from our PA-series or our SPA-series amplifiers.) Use solid dielectric 50 ohm coaxial cables rated for the expected voltage and current. Usually these are type RG-213 for high power or type RG-58 for low power. Avoid long runs of lightweight cable, and do not use speaker wires for signal-level connections. Shielding minimizes noise, interference, and ground-loop problems.

Yes. Shielding is strongly recommended for:

Audio input lines

Modulation connections

Low-level signal paths

Any cable routed near power lines or amplifier outputs

Proper shielding prevents unwanted noise, reduces hum, and improves overall system stability.

Power requirements vary by model. Most units will require a 19 to 24 volt DC supply for the logic and low level circuitry, while the RF power amplifier output stages will require a higher voltage and higher current capability, the exact values of voltage and current depending on the output power required. The product page or instruction manual for the unit in question specifies the correct voltage, polarity, and amperage. Using an underrated supply may cause shutdowns, reduced output, or instability, while excessive voltage may damage the device.

A few devices may be powered from a suitable battery pack as long as the battery provides the required voltage and current capacity. However, most of our amplifiers require voltages and current higher than a battery can supply. In such cases, if mains power is not available, a combination of a suitable battery and a power inverter capable of supplying the required amount of power may be used for portable operation.

Amplifiers and processors that operate under continuous operation or heavy load conditions will generate more heat and should be placed where airflow is adequate. Do not cover vents or operate devices in enclosed spaces without ventilation. If the device becomes excessively warm, reduce the load or power level or verify that the amplifier is not driving an improper or shorted load.

Yes. All Spectrotek products are designed with continuous operation in mind. As long as adequate cooling air is supplied, the power supply for the unit is working properly, and the unit is operating within its specified parameters, our amplifiers and other units may be operated on a 24/7 basis.

Never exceed the published maximum input voltage, maximum output load, or specified operating voltage for any Spectrotek device. Avoid short circuits on output terminals, reverse polarity on power inputs, and over-driving the audio input. Operation outside rated limits can cause damage not covered under warranty, and in some cases may pose safety risks.

The SSQ-2F processor was our very first Rife system controller board. It is a precision audio-modulated signal controller designed to generate stable carrier signals that can be shaped by an external audio source. Its purpose is to take a clean audio modulation signal and convert it into a controlled output suitable for use with compatible amplifiers or accessories. The SSQ-2F emphasizes waveform accuracy, predictable output level, and reliable operation over long sessions.

The versions differ primarily in operating features, internal circuitry, and the supported modulation modes.

v1.4x series — Earlier design, supports standard audio modulation. The output signal is digital TTL level only.

v3.21 — Improved output stability, refined circuitry, and expanded operating range. This was the first version that was capable of driving a small plasma tube.

v3.23 — This is the latest revision, offering the most stable operation, with enhanced modulation handling, and compatibility with a wider variety of audio sources. Also capable of driving a small plasma tube.

Yes. The SSQ-2F does not generate audio modulation on its own. It requires an external device—such as a sound card, MP3 player, signal generator, or other audio source—to provide the modulation waveform. Without a modulation signal, the SSQ-2F will not output a usable signal.

On the SSQ-2F and the SPA4, the 2× mode can be selected by using the configuration switches and duty cycle potentiometer as described in the product’s documentation.

In 2× mode, the device automatically outputs a carrier at twice the incoming modulation frequency. This feature is useful when your audio source cannot generate higher frequencies directly.

No. The output voltage of Spectrotek amplifiers is of too low voltage to ionize the gas inside the plasma tube. You must connect the output of your Spectrotek amplifier to the plasma tube with the use of an LC31 or an LC31L coupler.

Loads should match the recommended impedance and power requirements listed for your amplifier version.

Avoid short circuits, extremely low-impedance loads, or reactive loads unless specified as safe.

Spectrotek offers a variety of electrode sizes to fit different diameter plasma tubes. The exact selection is described on the Electrodes product page. All electrodes are fabricated from solid copper and coated with a high temperature heat radiating paint.

Always tighten the electrode clamping screw enough so that the electrode cannot slide from side to side along the length of the plasma tube.

Do not over tighten the electrodes as that will cause the electrode flanges to become bent and crushed. This may eventually cause the electrode to become loose on the tube after thermal cycling during use.

Be sure to use either the electrode wires supplied with the electrodes or use a pair of insulated wires about 8 to 10 inches in length.

Ensure that all connections are tight, clean, and free from corrosion.

Check these critical points:

If your equipment includes diagnostic LED's on the circuit board, observe whether they are on or off. Check the instruction manual to use the state of the LED's to determine where the signal stops. If all the diagnostic LED's are out, then check the following:

Audio source level — Most “no output” conditions are caused by a very low modulation signal.

Cabling — Ensure the output of the controller is actually connected to the amplifier input.

Power supply — Confirm the device is receiving the correct voltage and that the power connector is secure.

If these are correct, increase the audio source volume or try a different cable.

Many laptops and portable devices limit audio amplitude to protect internal speakers. Some implement software-based volume limiting that cannot be disabled. External USB audio interfaces usually provide stronger, cleaner output and are recommended when modulation levels are insufficient.

Intermittent operation is often caused by:

Broken internal conductors

Loose connectors

Worn or oxidized jacks

Low-quality patch cords

Replacing the cable is usually the quickest diagnostic test.

Pages are updated as new information, revisions, or corrections become available. New product versions or feature updates are posted as soon as they are released, and older pages may receive clarifications as needed.

Revision information is included directly on each product’s page when applicable. If you need historical data or want to confirm the revision you own, contact Spectrotek with your product’s version or approximate purchase date.

The Terms and Conditions page explains acceptable use, copyright restrictions, disclaimers, and limitations of liability.

All site content is protected by copyright and may not be redistributed or duplicated without permission, except for personal reference or as permitted under fair-use principles.

Yes. You may print or save copies of product pages, diagrams, or manuals for your own personal reference.

Reproduction for commercial or public distribution is not permitted unless Spectrotek has given explicit written authorization.