I’d been looking for oscillators with a few specific requirements. 1) Analog, 2) Phase Modulation, and 3) DIY. The LA 67 T-ZED Oscillator meets all these and was on sale at Modular Addict. It was not expensive at $140 USD for the full kit and it’s very easy to build.

T-ZED Features

• Simultaneous SINE, TRIANGLE, SAW, SQUARE, and variable SHAPE outputs
• Phase MOD input with bipolar INDEX circuit
• V/OCT input tracks 10 octaves
• FREQ spans 10 octaves, TUNE spans 1 octave
• Hard SYNC input
• SHAPE output (Sine to Triangle to Saw) with CV input and attenuator
• Frequency range HI: 10hz-25khz 
• Frequency range LO: 0,1hz-200hz 

A few things are unusual. This isn’t your general purpose VCO.

• The only FM input is the V/OCT input. There is no attenuated FM input.
• There is no Pulse output or PWM.
• CV Shape with initial and CV amount pots
• CV Phase modulation with initial and CV amount pots

I chose it specifically for the PM feature. The Shape feature is a bonus. Self-patched shape modulation from the other outputs yields more wave shapes. The Sine, Triangle, Saw, and Square outputs are pristine. No trimming needed.

Assembly

All the parts except for the power connector mount on the component side of the PCB. SMD is pre-soldered.

The one change I made was to substitute a 10-pin power header for the 16-pin supplied. T-ZED doesn’t use +5V or the other pins on the larger header.

I didn’t follow the recommended parts assembly order. Instead I placed the jacks, put the panel on and soldered them. Then I soldered the trimmers and then the pots. I soldered one support pin of each pot, placed the panel on and reheated a pot pin as needed to get them all standing straight. Finally I soldered the power header.

Calibration was easy, using the Mordax DATA to generate voltages and read the frequency.

Unusual Knobs

All of the pots are the (generally hated) tall trimmer type. But LA 67 added a twist: special knobs with indicator inserts that make them much easier to handle. They look nice, too.

Demonstration

You can watch a video demo on the LA 67 link above. I plan to make a little demo, too.