Soldering help,and which Square Red Light on a 73

mightymike · Post by **mightymike** » Wed Jan 12, 2005 5:28 am

Well I did it
I have the PCB out, and I'm installing the 69 brown board in my 73 JMP SL. I was able to lay everything out real clean and straight. I'm trying to use as much of the original wiring as possible to keep all the red dye, but there's a couple that won't reach

So I cut the wires at the board, but leaving just a bit of the plastic for future reference and tooks pic along the way just in case as recommended.

I need some soldering assistance::

I really want to do a nice job.
I'm in the middle of open amp surgery and I feel like I need to stop and practice soldering. I've ssen the pics on George's CD and mine just isn't up to snuff. How are you suppossed to hold the tip? Are you supposed to heat up the outside of the turret, while feeding the solder inside? Or do tip and solder both go in the turret? I can' seem to get enough heat with the first method.

Which Light:
I cracked my Square Red light and presence knob taking the chassis out of the case. Is that light a 6.3 Bulb? At George's store there's a $10 and a $4 light. With my luck it's probably the $10 one

I bet it's easier to wire build an entire amp kit, than to swap out boards while using the same wiring. This is my first time.

Post by **VelvetGeorge** » Wed Jan 12, 2005 2:59 pm

Just take your time on the soldering. Hold the tip on the outside of the terminal and flow the solder into it. Don't overheat though. You should only be heating it for 3-4 seconds.

Also, don't use an iron rated at over 30 watts. It's too hot unless you're experienced enough to control the extra heat.

Most early Marshalls used a 6.3 VAC lamp run off the heater supply. The 6.3V lamp I carry is expensive because it's an OEM Marshall part.
The 120 VAC lamp is a generic part that I offer as an alternative to the OEM part. But you have wire it for the AC supply.

George

mightymike · Post by **mightymike** » Wed Jan 12, 2005 8:43 pm

There's 2 black wires that hook up toward the diode side of the board.
One is the Filter cap lug wire, and that's supposed to connect to the jumpered electrolitic pair.(The one on the left)

The other black ground wire comes off the ground wire that grounds all the pots. That one was supposed to connect in between the diodes.

I have these wires switched because I was trying to use my existing wires. Lug wire to diodes, Pot ground to Electrolitics. So they're both grounded.

Would that hurt anything? They're both ground wires.

mightymike · Post by **mightymike** » Wed Jan 12, 2005 9:43 pm

Her's a pic