- Building a 'HomeBrew' StepStart Module -
Got some problems after i updated the AC Power feed to my shack. The automatic fuse 'blows' every now and then when i turn on my Dentron MLA-2500 Power Amplifier.

Decided to build an 'External' step start module to reduce inrush power when starting the PA. The external unit is preferred in my setup, mainly because there is almost no space to put the unit inside the MLA-2500 PA, also the unit is to stay with me, when or if ever replacing the PA.

2006.09.20 Unit now in place on the PA's AC feed cable. It's working fine!
Didn't need to adjust stepstart speed, when i moved one side of the relay circuit so that it's now connected after the 'Load' resistors the speed dropped. Also made some changes to the PCB layout.


Ready built module, mounted on the shack wall

2006.09.15 The 'StepStarter' unit tested and ready, the step time is quite long, maby i need to reduce the capacitor value, i return with more tests.


Ready built unit in the box, tested and working

2006.09.10 The unit is tested and working, now ready for the case, can't find any suitable casing at present time. Building is temporarily halted.

2006.09.09 Made the circuit board and soldered the components, initial testing is due this evening. You can read more about making your own printed circuit boards -->Here!

This is the components used for the Circuit
=====================================
2pcs Relay 1-pol 10A/25V                    37-206-87 
2pcs Power Resistor type AC15, 15W 22ohm    60-957-56
2pcs Electrolytic 100uF/100V                67-166-17
1pcs Power Resistor 2,2Kohm 5W              60-040-22
1pcs Rectifier diode 400V/1A 1N4005         70-004-09
1pcs printed sircuit board

Order# @ www.elfa.se
=====================================

Circuit drawing


Ready built unit PCB, Component side

- HomeMade circuit board -

PCB Layout

High resolution PCB image ready to use.

Description of how i make Printed Circuit Boards
Using the ET-10 etching tank and the homemade UV-Box.

This is the components used for the sircuit
===================================================
Qty  Component / Data                     **ELFA order#
===================================================
2pcs Relay 1-pol 10A TYCO RT174024 24VDC  37-206-87
2pcs Power resistors AC15 22ohm 5% 15W    60-957-56
2pcs Electrolytic capacitor 100uF/100V    67-166-17
1pcs Power Resistor 2,2Kohm 5W            60-040-22
1pcs Rectifier diode 1A 1N4004
1pcs printed sircuit board                HomeMade
===================================================
**http://www.elfa.se

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