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Re: Max Voltage for QMX 9V

 

I think the issue is that 12V pushes the voltage rating on the BS170's, and the increased current at 9V for the same power, ends up pushing the current rating of the parts.
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Paul -- AI7JR
On Mar 30, 2025, 17:35 -0700, KK4ITX John via groups.io <jleahy00@...>, wrote:

There doesn’t seem to be a clear consistent answer, the manual implies “a little over” is OK but does not define “little”. I admit that I don’t understand how a device that can handle 12v can’t go over 9v.

I do know that I have made contacts quite well with just 2 Lion 18750’s and they last for the duration of the park operation. ?The output is <4w, not a big deal.

Until we really know, just play it safe, many ways to keep the voltage under 9v.

John
KK4ITX ?

?Each mistake is a learning opportunity.?

On Mar 30, 2025, at 7:59 PM, Daniel Conklin via groups.io <danconklin2@...> wrote:

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You could put a small buck converter or a couple of diodes in the line to drop the voltage into acceptable range.
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73, Dan - W2DLC
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