Chuck D. Bones
Circuit Wizard
I pick up some GPCB Nostalgia Tone boards over the summer and have been breadboarding them. The Beano Bundle consists of a modified RangeMaster and a BluesBreaker. I breadboarded this (more-or-less) in its stock configuration. The only things I changed from the build docs was a C1K for HEAT and different transistor in the RangeMaster and different diodes (FD100 + 1N4003) in the BluesBreaker. You can find the schematics on the Guitar PCB website, so I won't repost them here. B1K also works well for HEAT. The various transistors I tried for Q1 are arrayed at the lower right (104NU71, MП38A, 2N2221, 2N222A, MPS6530, BC109C). They all worked well and did not require any biasing* changes. I ended up with a 2N1308 (HFE = 134).
* one could fiddle R4 to adjust the bias to taste. Because of their higher leakage & lower Vbe, the Ge transistors ran hotter (higher collector current). This lowers the voltage on Q1-C which produced more headroom for the resistor values shown. Higher HFE produced higher gain, but there was only a few dB difference between the transistors listed above.
Some great tones happen with the knobs set for just a touch of distortion. Cranking things up ain't bad either. Every knob does something useful. For the moment, I do not have the ORDER or BYPASS switches installed.
Knobs (L-R): VOL - TONE - GAIN - BOOST - RANGE - HEAT
* one could fiddle R4 to adjust the bias to taste. Because of their higher leakage & lower Vbe, the Ge transistors ran hotter (higher collector current). This lowers the voltage on Q1-C which produced more headroom for the resistor values shown. Higher HFE produced higher gain, but there was only a few dB difference between the transistors listed above.
Some great tones happen with the knobs set for just a touch of distortion. Cranking things up ain't bad either. Every knob does something useful. For the moment, I do not have the ORDER or BYPASS switches installed.
Knobs (L-R): VOL - TONE - GAIN - BOOST - RANGE - HEAT
![Beano breadboard 06.jpg Beano breadboard 06.jpg](https://forum.pedalpcb.com/data/attachments/81/81251-6a442f1b370cd884e895835b77193638.jpg)