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Re-using Molex PC connectors

Our summer weather ended this afternoon with heavy showers and 17C only.  HF propagation has been very disturbed. No decodes by VK7DIK on 80m last night it seemed to be restored. But only temporary, this evening again no grey-line decodes.
I had to move the Steppir control-box and rotor indicator to the shack. So did not have to be bored. Painting outside was not possible unfortunately ;-)


The PL259 as  tool to disassemble the PC power connectors..

The Molex terminals fit as plugs and sockets in this connector.

The Kenpro rotator that belongs to the Versatower  has a strange type connector ... 10 pole  idiot proof.
This old rotor has 6 wires. 3  for the indicator  and 3 for the motor.  
The voltage  of the  potentiometer in the rotator is simply displayed as 0-360 degrees by the voltmeter in the indicator.


My own newer type KR-400RC  uses 5 wires   2 for the potentiometer and also 3 for the motor.
The indicator has a  360dgs 500ohm potentiometer same as in the rotator. Both are part of a Wheatstone bridge. The indicator motor drives the scale to  balance.


I had to find a way to extend the rotor cable with 30m extra without modifying the connector.


The only plug that fits to this pins where the Molex power plugs used in PC's. I had some in the junkbox.
This Molex type connectors are ingenious simple and high reliable.
They where developed by Molex in 1950.

Now both controls are near the radio. 
The Steppir cable  was already about 30m long is extended to 60m using a cable with 25pole D-connectors. The cable is 0.25mm²  15 wires
It seems to work okay without extra Voltage boost.
The moral of this story do not clean out your junkbox too soon. 




Today morning 28MHz was good many decodes of VK2KRR (100W) and VK5AKK (10W)  and heard with 5W by both.
Also FR1GZ many decodes  T61AA & A45SWL  
But later ST0R was very weak and working  south EU only.





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Great and useful article. Creating content regularly is very tough. Your points are motivated me to move on.

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