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3 Relay Switching Board

The 3 Relay Switching Board is an add-on board that has 3 DPDT 5V relays and a power supply all on one board. It can be powered from either a 5V rectifier tap or 6.3V filament tap. If powering from a 6.3V filament tap with grounded center tap, the board can still be used if the board itself is not connected to chassis ground. Alternately, the filament center tap can be lifted, and referenced to ground via 100 ohm resistors (faux center tap). We've found that doing this, and referencing the board ground (marked 'G') to chassis ground, provides for an extremely quiet installation, even in high gain applications.

It was originally designed by Ampdoc for use in the Overdrive Special type amps, but can be used to switch any functions via 1, 2, or 3 button footswitches as needed. The board also has terminals to accommodate chassis-mounted LEDs, and can also be split into sections to fit almost any chassis - just connect jumpers from the B+ and Ground terminals to each section. An example wiring diagram is provided and can also be downloaded here.

*Note: All our shipping vendors (USPS, FedEx, UPS) have recently increased their rates for International Shipping. The shipping calculator will charge a fixed price, and we will invoice you any difference before shipping the product.

PRICE: $45 + $7 S/H (US)*

Prices subject to change without notice. Orders already in progress are not subject to price changes. Granger Amplification reserves the right to make any product design changes without notice or obligation to incorporate these changes in products previously purchased.

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All content copyright 2007-2011 by Blue Nite Productions. grangeramp.com is the website of Granger Amplification, a company that builds quality, custom amplifiers, one at a time, at very reasonable prices. Our focus is on producing all-tube, hand wired amplifiers based on proven designs such as vintage Marshall and Fender products, and other boutique amps, while charging a fair price. We also do kit building, modification, and repair work. We specialize in Plexi recreations, custom, boutique amp builds, and custom mods. All trademarks are owned by their respective companies and are only used herein for historical references. - guitar amplifier, amplifier, guitar, amp, amps, builder, for sale, fs, repair, mods, hand, wired, tone, custom amp, custom amps, amp mods, modifications, amplifier, handwired, point to point, tube, vacuum tube, valve amp, kit build, amp kits, made in usa, d18, e35, m45, m50, g50, cg50, lead overdrive 100, dragonfly, marshall, fender, jtm50, jmp, jcm, superlead, plexi, 15 watt, 18 watt, 35 watt, 36 watt, 45 watt, 50 watt, 100 watt, single ended, push pull, 5E3, bassman, matchless, trainwreck, express, epiphone valve junior, blackheart, tweed, deluxe, curt granger, birmingham alabama