full point
12-29-2005, 07:38 PM
Hi.
I'm trying to connect a 3 prong cord to the PT of an old Hammond Tone Cabinet Power Amp. Here's the schematic: https://home.comcast.net/~privatespotty/er20poweramp.jpg
Originally, when it was used with it's organ, it got power from another power stage in the organ through a 6 pin plug. Obviously, I don't have the organ and would like to throw it on the variac to see if it has any problems. Hence, I'll need to hook it up to a standard 3 prong plug.
(My next plan is to build it's proper pre-amp and make a nice little practice amp.)
Having recapped, retubed, and biased a couple of amps lately, I am still far from being a journeyman tech and realize that knowing how to make a proper plug should be par for the course.
My question is this: What wires from the PT where on the actual 3 prong plug?
From the schematic, I've isolated the "ground", the "+", and the "C". Given 3 places on the on the 3 prong plug, can someone tell me where they should connect?
Here's the map of the 6 pin plug:
Pin 1: To grid of one side of 6sn7.
Pin 2: To ground.
Pin 3: "C" on the PT.
Pin 4: "120 V" on the PT.
Pin 5: Hard to pinpoint (for me, anyway). It's tied to the reverb transformer, the plate of the 6sn7, and finally to ground. It goes thru other stages.....see the schematic (link above).
Pin 6: The grid of the other side of the 6sn7.
If I make this 3 prong cord, pins 1, 5, and 6 will need to be "powered" from elsewhere, no? Or are they apart of the circuit after pins 2, 3, and 4 are connected to the wall power?
I'm trying to connect a 3 prong cord to the PT of an old Hammond Tone Cabinet Power Amp. Here's the schematic: https://home.comcast.net/~privatespotty/er20poweramp.jpg
Originally, when it was used with it's organ, it got power from another power stage in the organ through a 6 pin plug. Obviously, I don't have the organ and would like to throw it on the variac to see if it has any problems. Hence, I'll need to hook it up to a standard 3 prong plug.
(My next plan is to build it's proper pre-amp and make a nice little practice amp.)
Having recapped, retubed, and biased a couple of amps lately, I am still far from being a journeyman tech and realize that knowing how to make a proper plug should be par for the course.
My question is this: What wires from the PT where on the actual 3 prong plug?
From the schematic, I've isolated the "ground", the "+", and the "C". Given 3 places on the on the 3 prong plug, can someone tell me where they should connect?
Here's the map of the 6 pin plug:
Pin 1: To grid of one side of 6sn7.
Pin 2: To ground.
Pin 3: "C" on the PT.
Pin 4: "120 V" on the PT.
Pin 5: Hard to pinpoint (for me, anyway). It's tied to the reverb transformer, the plate of the 6sn7, and finally to ground. It goes thru other stages.....see the schematic (link above).
Pin 6: The grid of the other side of the 6sn7.
If I make this 3 prong cord, pins 1, 5, and 6 will need to be "powered" from elsewhere, no? Or are they apart of the circuit after pins 2, 3, and 4 are connected to the wall power?