Wiring Help

[pro_crip]

Hi all,
Okay, I've got everything physically situated in or on my chassis. Now, the problem is I'm not sure exactly how to wire everything together. Mainly, it's the connections to the speaker terminals, rca jacks and switches that have me flummoxed. If someone could kindly point me to a relevant source of info I would be grateful. TIA.

Rich

[ashok]

Rich,

I used the logical layout diagram of the ST35, which is part of the printed manual. Be sure to use the one that corresponds to the transformers
you are using: Hammond vs Dynaco. The connections are essentially the same but the colors are different. Also, with the dynacos, feedback is out of the 16 ohm tap.

For the speaker connections, I simply followed the color code as shown in the logical diagram. For example, I connected the yellow wire from one of the 1650F transformers to the positive (red) speaker terminal of that channel. I terminated the yellow wire on a ring-type termination lug. I prefer to solder the wire to the lug. For the feedback, I took a piece of wire with suitable terminations at each end, connected one end to the same speaker terminal and the other end to pin 3 of the J3 terminal block on the PCB.

Repeat the process for the other channel. Follow a similar method for the ground connections to the speaker terminals. Note that both the black/yellow and black wires have to be terminated at the speaker terminal. An extra wire is required to connect the speaker ground to pin 3 of the J2 terminal block.

I am not using the 4 ohm taps. So I shorted the green/yellow and green wires together, as shown in the diagram, but left them inside the chassis. I used a twist-lock type of termination for this.

For the RCA jacks, I used a pair of hookup wires for each jack. One for the signal, and one for ground. The ends of the wires, after suitable termination are connected to terminals blocks J6 and J7. Ground is on pin 2 of J6 and J7. On the RCA jack side, you will have to solder the wires to the jack.

My amp does not use the standby switch S2, so I simply wired the red/yellow wire on the power transformer directly to pin 5 of the J1 terminal block. You will need hook-up wire for the ac input portion if you are using an IEC receptacle. If your power cord comes into the chassis directly via the strain relief, you most probably will need hookup wire only for connecting the fuse to switch SW1. Again, the position of the fuse, switch and PCB in the chassis will dictate this. Connect the black wire of the input cord to one end of the fuse; the other end of the fuse to pin 1 of SW1 using hookup wire; pin 2 of SW1 to one of the black wires of the power transformer. The other black wire of the power transformer goes to pin 10 on the J1 terminal block. The neon bulb on the SW1 should be in parallel to the primary winding of the power transformer. So, I connected pin 3 on SW1 to pin 10 on J1.

I hope this helps you. My apologies if I misunderstood your question.

Ashok