Gyraf Pultec finished (Shopping list included!)

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The CK1030 you link to is for wire mounting - for PCB mount like the original you'll want CK1050: CK1050 | Drejeomskiftere, 6 Positioner, 150 mA ved 250 V ac, 250 V dc, 250V ac | RS
Hej Jakob.. ive replaced the rotary switch and it sounds better now..
however, I've noticed that the other knobs (CUT/BOOST pots & FREQ switches) are crackling / pops / noise when I turn them. kinda like changing channel on a radio. It's been a while since ive used my pultec, so I can't remember if these noises were always there.

Is this normal?
If not, would it help if I replaced all those switches/pots as well, perhaps with higher quality ones?
 
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the switches will do some clicking, that's impossible to avoid - but the pots should behave better.

Unfortunately, massaging the pots didn't quite get rid of all the crackling sounds. So i'm replacing all pots with Bourns and getting new C&K switches with MBB. They might have been oxidized, being that my studio is in a basement.. and I don't wanna risk wasting time cleaning them with contact-cleaner.
Anyways, I'm replacing pots and switches with new ones because my unit is getting a makeover with an output transformer for the input and Daka-Ware knobs.

Q1: Looking thru my unit, I noticed that it doesn't have the LM317 regulator. Just 3 wires connected to pins.
Do I need it? What's the deal with having it versus leaving it out?

Q2: The xlr inputs goes to the unbalanced input on board and not balanced.
When and why should I chose one over the other?
 

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1) - look at the schematic, read the description, figure out what is going on. The LM317 is for regulating the 6.3V DC for the heater for the tube - without it you don't have heating for tube (unless some other solution is there) and it won't work. reason for wires to 317 is so that it can mount to chassis (isolated!!!) and thus get better cooling

2) If there's no input de-balancing trafo, this is where input goes. Otherwise no sound comes to the circuit

/Jakob E.
 
1) - look at the schematic, read the description, figure out what is going on. The LM317 is for regulating the 6.3V DC for the heater for the tube - without it you don't have heating for tube (unless some other solution is there) and it won't work. reason for wires to 317 is so that it can mount to chassis (isolated!!!) and thus get better cooling

2) If there's no input de-balancing trafo, this is where input goes. Otherwise no sound comes to the circuit
You're right Jakob, thanks, it was hidden and looked like it was a GND connection initially 😇 stupid me, this is embarrassing! Shouldn't look into my units in low lighting.

2. the reason I asked, was because there's an optional balanced input next to it.
I was just wondering why this wasn't used instead.
My unit is a few db lower when audio is returned from it, so I thought maybe this had something to do with it.

I'm gonna order a LL5402 for the input, then I can re-wrire the input xlr to the balanced input, correct?
 

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