Flight of Harmony Famine 1500 is a voltage-controllable power starvation module. Famine restricts the amount of power sent to modules, starving them, causing erratic behavior. In Feed mode the module is bypassed completely and the +/-12V power is sent through. (The +5V power is passed through at all times and is not starved.) Famine can put out as much as 1500 milliamps (1.5A) per rail, if your power supply can. It comes with high-current connectors, if you need them.
In Starve mode the output voltages can be varied between 10.5 volts and 3.0 volts. In All mode the left knob and CV input control both the positive and negative voltages. In Split mode you have separate controls over the two voltages.
The LED eyes in the skull glow brighter as starvation increases (i.e. output voltage decreases).
But Why?
I had the idea of power starving my Ieaskul F. Mobenthey (IFM) modules, designed by Peter Blasser. The IFM modules are all analog and draw very little current (around 100ma for my entire IFM set). I figured they would be safe for starvation, and they are. If you ask why I chose the 1500 instead of the 4hp 500, it’s because 1) the 1500 was available first, and 2) the 1500 is shallow and easier to build.
Building the kit
Famine 1500 is built on a single PC Board having components mounted on both sides. The front panel-facing side holds all SMD parts, as well as pots, jacks, switches and LEDs.
The back of the board is also the back of the module. It has the power input and output connectors, plus the voltage regulators in their heat sinks. I did not mount the quick connect high current tabs, since I am using this with a low power setup.
Testing
I discovered that the module needs to have some load for the voltages to be stable. So, after I did the smoke test (and saw no smoke) and measured the voltage outputs, noticing a fluctuation going on, I plugged in a small mixer module with a current draw of 40ma per rail. That load stabilized the outputs.
To measure the output voltages I needed to put my voltmeter onto the Eurorack power pins. This is always a pain, because you have to do it manually and be very careful not to short out pins. So I made this power cable with banana jacks for the +12V and -12V wires. No need to have a zero volt jack here, because all my cases have a banana jack for the zero volt (ground) connection to the power supply.
A small problem
The skull LEDs are expected to get brighter as starvation increases. Well, I found the negative (right) side LED was always on. It would get a little brighter as starvation increases. I couldn’t see anything wrong with the build or find anything suspicious by resistance checking. So, dagnabbit, I contacted Flight of Harmony about this. I got a quick response with the explanation that a transistor might be bad or else a resistor value needed to be changed.
After removing the panel. I replaced the SMD 3906 transistor with a TO92 size 2N3906. That didn’t fix the problem. So then I put a potentiometer in parallel with the resistor in question and as I lowered the resistance, the LED did dim and go off. I replace the SMD resistor with a 1/4 watt one, a kinda tricky operation. Final outcome: LED is off when starving is bypassed, but glows just a little when the -V out is at full.
The next post will have a demo of the Famine in operation.
Excited for the Demo!!