Building the Signal Clone

The Signal Clone is a 5×1 buffered mult for CV, gate/trigger/clock, or audio signals. One of the outputs is inverted. The circuit is built around six Opamp buffers, with one used to drive a bipolar LED to indicate signal polarity and level.


BOM:

Qty
Value
Device
Package
Description
Source 1
Source 2
6100nCapacitor0603! 0603 Package !
210uCapacitor0805
21uCapacitor0805
2M7 (1N4007)DiodeDO214Polarity protection diode.https://octopart.com/search?q=rectifier&start=0&category_ids=4226&specs2.2.values=SMA&specs2.330.numbers=(50__200)&specs2.313.numbers=1&sort=median_price_1000&sort-dir=asc
1BicolourLED3MMBicolour two-pin LED (red green)
2100KResistor0805
5100RResistor0805
51KResistor0805
11MResistor0805
14K7Resistor0805
3TL072OpampSO08Almost any dual Opamp can be used.https://octopart.com/search?q=TL072&start=0&specs2.2.values=SOIC&specs2.2.values=SO
63.5mm Audio JackTHONKICONN3.5mm socket for Eurorack modular synths "Thonkiconn" style.http://shop.erthenvar.com/collections/accessories/products/3-5mm-inline-jackshttps://www.thonk.co.uk/shop/3-5mm-jacks/
1Tile power tail"Futaba J" type power lead.http://pulplogic.com/product/tile-tail/EBay

Schematic:


Build Instructions:

 

Clean PCB with isopropyl alcohol to remove any manufacturing residues.

Solder the surface mount devices, then the power tail.

 


 

Add the LED and 3.5mm jacks.

The LED sits tightly between the two right-most jacks. The outer ground pin of the jack should be pushed against the body to make room for the LED before soldering.

 


Testing:

Check soldered connections for shorts, especially between the Opamp legs.

With a multimeter, check that there’s no shorts between the red, white, and black power leads.

Apply power and patch a bipolar (+5 to -5) LFO to the input. The LED should alternate colours and intensity with the LFO.

Check that each output is sending  a copy of the input, and the inverted output is inverted.

 


Done!