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Matchless Hot Box TRUE Bypass

7/24/2004 6:42 PM
Matchless Hot Box TRUE Bypass
Is there a schematic or even better a lay out diagram around for converting a Matchless Hot Box to true bypass. A friend of mine some time ago installed a bypass, but this is not a true bypass. As far as I know, one not just needs a DPDT stomp switch, but a 3PDT switch - or even more? I have a Fulltone 3PDT.  
P.S. Though this is a widly felt issue, I could not find any information on the internet on how to actually install a true bypass to the Hotbox.
7/27/2004 12:49 AM
Can't speak to the Matchless specifically, but GeoFex has some good articles on bypass switch circuits.  
Basically, it's possible to rig up a DPDT switch to provide true bypass switching and also switch an LED on and off. Check out the articles on "Millenium bypass."  
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8/23/2004 11:45 PM

Coupla things to consider...are you comfortable with high voltage circuits, lead dress with a high gain circuit in close quarters, and rewiring it?  
Do you care about resale value?  
Would true bypass with just a DPDT stomp switch and no LED anunciation be acceptable, or do you wanna see when the signal is being modified by the circuit?  
Even if you don't wanna use the Millenium Bypass and would rather use a 3PDT, you'll still need a low voltage tap and current limiting resistor for the LED. You can develop the low voltage source off the main B+ using a zener or voltage dividers and capacitance...the current draw may cause you to get some voltage drop to the business end of the circuit which may affect tone.  
OTOH, you can develop the low voltage tap by rectifying and filtering from the 6.3VAC heaters (I don't recall if the Matchless uses AC or DC on the heaters) in some settings, this may introduce noise into the signal.....  
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