Internal power reduction for linear drive

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  • Updated 1 year ago

So just thought I'd share this worry  that may prevent a total disaster for linear operations. Likley covered elesewhere, but I couldnt find a similar post.

About 1.02 mm above the MOX button in Smart SDR (e.g. width of a gnats dick)  is a drop down menu that allows you to "accidentally" change your transmit profile from a safe 25 watts to 100 Watts instant LDOMS kill mode !

This is VERY VERY VERY easy to accidentally do, almost without noticing, if you do not keep you're eyes 100% on the screen. I’ve managed to do this frequently and find it such a high risk drop button to have so critically close to MOX.

Using a single profile is a safer option but still makes me nervous - one day, being human, likely I'll screw up.

Is there a fail safe way to reduce RF power output within the radio (convenient little pot maybe ?) to "physically" drop output down to 25 watts for peace of mind ?  Or if not, may be have Mr. programmer move that drop down somewhere else.

I appreciate there is a Max Power override button on the TX setup screen , but again easily overlooked or maybe removed if loading new software etc. Just a thought ....



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Keith Richards

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Posted 1 year ago

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Bill -VA3WTB

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When you open that box up, don't you have to select a profile?  before changing to a new one?
The software remembers the last power setting you used.
In each profile make the max power the same, so no matter what it will never go over what you want.

I am making these suggestions as never having this happen here that you have.
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Dudley - WA5QPZ, Elmer

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There is a max power limit setting already in the Radio setting, set it for a max power output never to succeed. This should address what you are looking for. BTW, watch out for and external program that uses CAT commands to control RF power, this can over ride your profile settings too . Your amp should be able to protect itself too, even if you should accidentally jump to 100 watts.

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Hello Keith and Happy new year

You mean you hit the "Select TX Profile" drop down?
easy to remedy
Go in and delete the higher power profiles or
build several Low power Profiles so you have to scroll down to find a higher power profile or 
go into "Settings, Radio setup, TX" then set the "Max Power" to what you want the MAX power to be. 

The later is the safest method by far. 

I can't say I have accidentally open'd the "Select TX Profile" drop down probably because I don't use the MOX button very often.
I always run my station remote and I use the CAT PTT function with a com port PTT button when running SmartSDR, much more convenient and less of a hassle then to find the MOX button twice on every transmission. 

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Stan, K4SBZ

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Hi Keith,

Something else to consider is using VOX on SSB. I do and seldom have need to hit the MOX.

Stan, K4SBZ
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Ross - K9COX

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Please tell Mick hello