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Power supply choices

I have a Powermax 100 amp and plan on using it with my RCI2970N3. Still looking for the best voltage to set it on for safe use either the radio. This is like a mystery it seems. I have it set to fixed output not charging. I think I eould rather the fan run all the time than just come on when it starts getting . What voltage do most run for their 300+ watt radio like a RCI2970N3

RTFM for the radio equipment for the best voltage to set it at.
13.7V - Unless I'm wrong, that is operating vehicle battery maintenance voltage
I don't know whether my RCI2970N4 would operate on anything higher than 13.7VDC. It doesn't have an indicator of voltage draw.
Sadly my PM3-75 doesn't have means to set steady voltage. I concluded the LK as in PM3-100LK is the version with this capability. Will you verify yours is an LK version?
My Stryker SR955 shows LCD voltage readout. I adjust DaveMade PS200 to 14.7V output and Stryker shows waffling between 13.7 and 13.8V.
I don't doubt my linears, any one of 3, could benefit to a small inconsequential degree at 14.7; but the radios, I believe, have strict voltage regulation circuit.
I also do not believe in not taxing this circuit; so, 13.7V it is.

Recently received Fleebay offering for BLUE LED FAN KIT BASE STAND w/ Built In Ext Speaker RANGER RCI 2970 N2 N4 Radios. Maybe bloated pricing but Foot print width sits comfortably atop Cobra 2000 speaker. I believe the N3 is also sized right.

View attachment 60618

Sturdily built with wrinkle coating. You can just barely make out the toggle switch, center underside front. Almost inaudible fan.

As to fan on your Powermax PM?-100*. I imagine there is an operating temperature for peak efficiency. In a bone chilling operating environment this operating temperature may never be realized with the fan on constant.

The Powermax Charger/PS, LK version, is IMHO the best! It's not a gifted with front face metering and never used front knobs. Ok, once in a blue moon you might think about tweaking 'em, just cause you can. On that blue moon occurrence take out a Phillips and tweak voltage output on your PM PS. Doesn't take a genius to build an external box with dual meters; I dun did it. Tuck the PS away remotely and route small neatly packaged auxiliary meters front and center. The PM has flexibility of uses, as long as it is the LK version; more than the numerous others costing more for far less amperage;


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I build my own cooling fan stand including a temperature controller that turns on the fan at a desired temperature setting. The fan is a 200mm fan and moves a buch of air very quietly. Controller and fan I bought on amazon. The 1/2 pvc sheets I made the stand out of I already had. Total cost $33
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