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UREI 1176 FET COMPRESSOR - THE MAKING OF

1st STEP: Getting the components STANDARD COMPONENTS Standard electronic components from www.reichelt.de I’ve got all capacitors, Resistors, Wires, Sockets, IC’s, Voltage  Regulator 7824, and some Transistors from them. The partlist shows 1k1 Resistors... in the component drawing there is a 1k1 resistor with 1 Watts! You have to observe this. TRANSFORMERS The lundahl Transformers: Bought them directly from www.lundahl.se. I’d contacted Per Lundahl himself under the official email adress. ;-) (his server was out of work, so the order could sometimes last longer) ;-)) The lundahl transformers i’d seen in CADAC consoles and they are optional at spl stuff. I bought the LL4502 OUTPUT TRANSFORMER and the LL1540 INPUT TRANSORMER (the input transformer is optional, you can do a 1176 without that. PDF document for the LL1540 PDF document for the LL5402 SOME “HARD TO GET” COMPONENTS The SIFAM VU-meter seems to be in very good quality. The price is just high for a vu meter. I think i’d read that they were used in neve consoles as well. In Denmark you can order the parts (meter, bracket, lights) like written in the partlist, but as i would buy them at  www.farnell.de it seems the SIFAMs aren’t in stock... :-( I’d bought the potentiometers from radiohm. But the 4M7 log Pots are hard to get. In this case... buy the stereo version! The “low leakage diodes” FDH333 or BA195 were only found at www.farnell.com. If you’re thinking about using other diodes linke 1N4001... this isn’t a good idea, because you’ll get  problems with the VU-meter. It works in mA range. So it’s important for a working vu-meter to get these parts! I’d also problems to get the simply and often used BC107. There are several types of transistors BC107A, BC107B, BC107C... But you can buy “b” or “c” types.   Be careful with the FET BF245! This must be “A” type (BF245A)

ETCHING THE PCB First you have to make the 3 pcb’s, the mainboard and the two boards for the switches. These ones was made by a friends friend. But i will buy an etch machine from “isel” soon. Then you’ll find more informations about etching here... of course only if i not etched away ;-) I’d drill the first 1176 board by a friend, because he had the  cool proxxon machine and hard metal drill bit. At the moment i’d bought a new drilling machine...

PLACING THE COMPONENTS ON THE PCB Drawing the components on the pcb (printed circuit board): So i know that i’d drill all holes for the components.. Wiring the compoments:

Labeling the frontpanel: The switches, are e.b. used by drawmer (here a 1960 tube mic/preamp)... ...and also used by CRUMAR, an old analog shynth... uhh many of these switches ;-) here i had to change 2 switches for the waveform (often in usage)