Seventh Circle Audio

What is the grey fish paper that goes under the input transformer? What does it look like? I do not remember getting anything like that in the kit?? What is its purpose?

I assembled my two A12 kits this weekend and everything went well. I was short part R21 in each kit which I thought was weird but luckily I had a few spares lying around so no worries.

I was curious about the fish paper. I did not know what that was and I did not see anything that was a gray paper. I saw a gold foil sticker and I thought, well this is the only "paper" type thing in the kit so this must be it. I stuck that to the bottom of the input transformer and soldered it to the board.
I feel pretty stupid now. I decided I should read the other kits instructions to see if this mysterious fish paper shows up anywhere else. I discovered that the gold foil sticker is for the stop pin on the other kits. WAy to go me!

OK, great. So I dont have that fish paper (still not sure what it is), and Im worried that the transformer is going to melt my preamp. Any suggestions??

Thanks!!

Caleb

The fish paper is like grey construction paper that fits over the pins on the input transformer. It prevents the transformers from shorting out any of the traces underneath it on the PC board. It is only used as an electrical insulator.

I wouldn't worry too much about it if there's nothing shorting out now. Maybe someone more authoritive can chime in to giver their opinion. I think it's mainly so that solder doesn't come through the trace and contact the transformer shield, shorting one of the pins to ground.

Shane

P.S. the gold foil sticker is for holding in the stop pin on the Grayhill rotary switch. If you used it on the transformer you'll probably have to use tape or something to hold the stop pin in.

Im not sure if it is shorting out or not because I have not powered them up. My CH01 and PS02 are supposed to be shipping sometime soon. I think Tim said he was out of those or something.

I dont think any solder went through to the underbelly of the xformer. I will look to see if I can see that far in or not.

I am under the assumption that the A12 does not require the stop pin??

Thanks for the help.

You do not NEED the stop pin, but without it after the 12th gain step you'll return to the lowerst (1st gain step). Also, you run the risk of turning the gain down one step too much (bacwards) and clicking the unit into 100% gain (which could end up in exploding headphones if not careful! )

I think it isn't TOO likely that the solder will flow through since there's no heat on the outer casing of the transformer for the solder to flow to...but hopefully Tim will be back soon and give a final ruling.

You;ll know if theres a problem when you first use the unit though.

Shane

As long as it does not blow up in my face. HA HA.

Which hole do I insert the stop pin into?

Nerdyrocker \$m[1]:As long as it does not blow up in my face. HA HA.

Which hole do I insert the stop pin into?

Check out the N72 build instructions. There is a picture that shows where
the stop pin goes. It's the same for the A12.