Re: full rig power control unit


Agreed, but any fault turns OFF Q1 and thus D4 the 'fault' LED.   My reading of the schematic says that the text 'Operate" and "Fault" is transposed on the LEDs's.


On Thu, Mar 1, 2018 at 05:28 pm, K9HZ wrote:

To be clear, the SCRs trigger the RS flip-flop into the RESET (FAULT) state and it stays in reset until the fault condition presented by the SCR has been cleared.  THEN and only then can you SET the flip-flop (NORMAL) such that power is reapplied through U2.



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From: [] On Behalf Of Glenn
Sent: Thursday, March 1, 2018 6:42 PM
Subject: Re: [BITX20] full rig power control unit


I only see one 62R resistor. I assume you mean that one is 68R ?   C10 & C11 are not in the bill of material.

Did you see my other post re the apparent reversal of the 'operate and fault' led's?

The reset switch does not reset the SCR's. Only the astable.




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