START CAPACITOR ADDED INTO BLOWER MOTOR CIRCUIT
Since I replaced the blower motor with a similar but not identical one, the current start relay wasn't able to start the motor spinning. It should kick in momentarily then disconnect the start winding as the motor rotates up to speed. I found that I needed to introduce a couple of microfarads of capacitance into the start winding circuit to introduce enough phase shift to reliably start motor rotation.
I added this 2.2uF capacitor in series between the start relay and the blower motor's start winding. It fires up nicely and reliably now.
FILTER INSTALLED INSIDE PLENUM OF THE DISK DRIVE
This filter was close enough in size and appearance to be substituted into the drive. It is important that the air being forced into the disk cartridge and out across the disk heads is free of particles in the 3 micron and larger range as the heads fly at about that height over the disk surface.
TESTING AIR FLOW WITH FILTER INSTALLED
Quite satisfied with air volume coming through the filter and out into the disk cartridge.
PCBS ARRIVED - STARTING TO SOLDER ON PARTS TO BUILD THE CARD
I have installed all the components on the front of the PCB, but have 22 decoupling capacitors to solder onto the rear of the board to complete it.
The board is well sized to sit atop the donor SLT double card where it will be attached. I took this picture after only having installed the voltage regulator that drops the +12V supply down to produce the 5V needed for all the 74LSxx chips.
Once I finish the parts, the board has to be assembled onto the card. Two holes will be drilled to mechanically anchor the PCB.
I will tack on some wires to the donor SLT card and solder the other end onto my PCB, completing the connections.
I will put this on the testbench and power it with +12V which is the only 1130 supply voltage that it will use. I can then set up the input pins to put it through its paces.
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