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). It’s never been easier to add channel switching to your amp.

The OptoFET Channel Switch Jack operates from a standard footswitch pedal (latching Tip/Sleeve). The PCB has additional switch terminals, so an external mini-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 (with or without jack mounted, select from dropdown)
– 3 feet of RG-174 shielded wire (option to add up to 10 feet)
– 2 feet of 22 gauge stranded wire for filament supply (or power source) connection
– Heat shrink tubing, and installation instructions (downloadable after order completion) are included.

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.]

Pricing and Options

(1 customer review)


3 in stock (can be backordered)

Additional RG-174, per foot (limit 10)

1 review for OptoFET Channel Switch Jack

  1. Guy Thomas

    I absolutely love this OptoFET Channel switcher with jack, made it so… easy to install channel switching. It only to me about three hours. I think it will only take me about 2 hours when I do it on my other amp. Very happy with this.

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