Re: Hoffman Princeton Reverb Turret Board

[Woodsmoke]

Hey Doug/Whomever,

I have one of your turret boards and layout instructions for this amp (non-trem version) and have a question-  I've omitted the 5U4G tube in favor of a couple diodes (each on the 325 reds, then running to the standby switch).  Do I need to connect the yellow 5V rectifier leads from the PT to this circuit or can I seal and tie them off (leaving them out of everything)?

Bonus question, what value resistor should I put in series with the diodes to create the same voltage drop (or thereabouts) as the missing rectifier tube?

Thank you!

[eleventeen]

5U4 drops 45-50 volts.


A resistor does not really do quite the same thing as the internal voltage drop of a 5U4, but I would start my calcs as follows:


Typical amp current figure 60 ma. (.06 amps)


45 volts / .06 = 750 ohms.


Power: I*I*R = .06 * .06 * 750 = 2.7 watts


That R can and will get hot, I'd get a 10 watt.


Yes, you can tape up the 5V windings. 

[Woodsmoke]

Awesome.  This is everything I needed to know.  Thank you.