I did a quick test just to see if all the FAB Modules work and play well together.  I’m very pleased with the results…. The modules were quiet, and even with a long signal chain as you can see in the picture, there was hardly any noise I could hear.  (For testing, I hooked up a condenser microphone and connected the outputs to a KRK RP8 8″ Monitors. No humming, no RF noise, nothing.)

Everything works… the logic control Phantom Power, -20dB Pad, Polarity Reverse, and the +6dB Boost (1:2 Transformer Ratio).  To get the FAB4312 Non-Inverting Amplifier working, I hooked up a small 10K potentiometer so I can adjust gain.  For now, I just used a jumper and connected the Phantom Power Logic control inputs directly to a spare V+ terminal on the FAB1215 PSU module.

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Mouser.com put a crinkle on my plans when I learned that one of the part I need for my FAB1215 is out of stock. There’s (22) pcs on order, but they won’t become available until May…. so all in all, it’s not looking good… Mouser may just stop carrying this part suddenly.  I emailed them asking about their future plans for this part, whether they’ll be continuing to carry it or not.

Here are some photos showing the FAB1215 Power Supply Module powering some FAB modules via a ribbon cable.

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Here’s a photo of our FAB1215 Power Supply Module, outfitted with our DC-1248 (+48V converter module).

I finally got the chance to test the 48V power supply by hooking up our FAB2010 XLR Input Module, FAB2110 Input Transformer Module, and FAB3010 XLR Output Module, using them as a pass-through before going into an API 512C preamp.   But instead of turning on Phantom Power on the API preamp, I used the 48V source on our FAB module.

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Yesterday, we got the boards back from the PCB fab house. Today, I built the FAB1215 prototype and tested it.  Now, we have a power supply to power all our FAB modules. Yay!

This convenient power supply is powered by a simple 12VDC power adapter (wall wart). The one I’m using is rated 400mA and it’s the only one I can scrounge around… but I’d recommend a 1Amp power adapter so you have plenty of power to spare.

The +/-15Volts is generated by an off-the-shelf part, and the +48Volts for phantom power is generated by our DC-1248 Module (12VDC to 48VDC converter).

The FAB1215 has (1) DC jack to accept the 12Volts input, and (2) IDC headers that route +/-15Volts, and +48Volts so you can power (2) channels of your project.  The +/-15V is rated up to 190mA, and the 48Volts is rated up to 60mA  (this 60mA figure may change once I finalized on the component values and complete testing).  You simply hookup power using 10-pin ribbon cables to your FABs. It’s that easy.

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