Tweet
Hi there.
This question is for all the amp gurus out there. I need to decipher a tone stack from a picture, or few pictures. I know most of the resistor values and have an idea how they are connected but not 100% sure. Anyone with a keen eye and knowledge for out of the ordinary and strange tone stack circuits may help me to draw out the schematic for this amp. This is a Dallas Rangemaster 5412 model with tremolo.
The tremolo section will be the next challenge by the way. I attache a few pictures from different angles so you can see and hopefully figure out the circuit. A brief description of the pictures;
The decoupling cap that feeds into the tone stack is a 10nf and appears to connect to the treble pot's top connector. ( The top of the picture is actually the earth leg of the pot!) From where the 10nF connects, there is a 100k resistor connects to a junction of an unknown cap (it's leg looks like to connect to the earth leg of the treb pot) and a 220k resistor. The other side of the 220k resistor joins to another 220k resistor and perhaps to the centre wipe of the treble pot,(this is not sure though!). On the middle of the treble pot there are two 470k resistors, and they are seem to have been joined on the left hand side. This is where the next stage input shielded cable connects. Underneath that there seem to be a small ceramic type cap covered in wax? The topmost 470k resistor comes from the wiper leg of the bass pot through a shielded cable that is shielded (soldered to the treble pot's earth, top of picture.) The bass pot is on the right hand side, and it is the on/off switch at the same time.) It could be 1M or 500k, I am not sure. The bottom resistor of that pair connects to where? Also there is a ceramic cap coming from the top leg of the bass pot and joines to? (it could be the top leg of the treble pot, but this is only guessing.)
The sizes of the two ceramic caps indicate something like 3.9nF or 4.7nF - ish? The wax covered cap is more like the pF range, 100pF maybe?
These are all the components of the tone stack. Can anyone figure out how they could be connected and work? Any help would be greatly appreciated.
Attached Files