OptoFET Channel Switch Jack

Now shipping version 1.4 red boards. The Granger OptoFET Channel Switch Jack allows noiseless signal routing without clicks or pops that are usually associated with electromechanical relay-based switching. The small board (2.25″ x 0.875″) fits into a single unused, or newly drilled, (0.40″) jack hole. The board features two opto-MOSFET Form C relays, which provide two normally open (NO) and two normally closed (NC) contacts (DPDT). The relays have an on resistance of 6-10 ohms and an off resistance of >100Mohms. A simple connection to the existing 6.3V filament supply (from any tube) powers the board. The active relays have very low power consumption and very fast switching times (1-3mS)

The OptoFET Channel Switch Jack operates from a standard footswitch pedal (latching Tip/Sleeve). The PCB has additional terminals so an external toggle switch can also be wired to override footswitch control.

Should you need more than 2 relays, we now offer our OptoFET Daughter Board, which has an additional two relays, and standoff mountings (2).

PCB-jack assembly, shielded wire, and installation instructions are included. It’s never been easier to add channel switching to your amp.

DISCLAIMER: User assumes all risks. Performing these modifications will most likely void the warranty on your amplifier. Working on amps can be deadly if you do not take proper precautions. Read and follow the diagram or instructions very carefully. Basic soldering skills and basic user-supplied tools are required. If you are at all unsure of your ability to perform these modifications STOP and take your amp to a professional to be modified. You can also send your amp to us for modification. Contact us for pricing.

Beginning in 2018, instructions are now online for your convenience. This allows us keep our prices competitive, and helps all of us reduce paper waste. Links to PDF files will be included in the order status email, and your order history. Please add grangeramp.com to your email whitelist to ensure you receive our emails.

DIFFICULTY LEVEL: INTERMEDIATE [Follow safety guidelines for working with electricity. Basic soldering skills and knowledge of working with AC/DC circuits. Identify all terminals of electronic components using data sheets. Read resistor color codes and capacitor values. Measure and connect high and low voltage AC and DC. Understand basic working of vacuum tubes. Use all functions of a multimeter. Understand Ohms law and apply to basic circuits. Work with basic hand and power tools.]