Guys it is not the heater that is doing the play,it is the shitty PSU,and most of all the shitty potentiometer they used on it . I have a couple and the first one came in like that the second one developed the same issue over time. You can see how people in Woodscents and the E-nano threads are striping their knobs with bands,lol.. Cause even the most miniature of movements makes it jump a few.
@Hippie Dickie has mentioned on multiple occasion the downsides of the knob mechanism. The accuracy of the knob controlled isnt as precise as buttons where you can do 0.01 steps with ease,while with knobs most of the times you have to act as a DJ or just be ok with the number on display not matching the one in your mind,after all with some heaters 0.1-0.2 isnt that big of deal. There are these small multi turn potentiometers (little blue blocks) that get turned with a screw driver,they are somewhat more accurate than the knobbed ones,but still like their big brothers they get fucked up over time and develop a dead spots which makes for big jump in numbers and maimung even further the accuracy.
Saying all that i get it that knobs are still more comfortable with most of the guys because of the analog feeling,but they will get fucked up quicker than the buttoned ones.Replacing is not a big deal if they last you a good ammount of time. Shitty quality ones like in those PSUs come sometimes fucked out of the box or develop those issues much sooner than the high quality ones(like those seen on higher end audio equipments). Thing is the volume of sound doesnt have to be that precise to be pleasurable.
Would have your air conditioner controlled by a knob ? Maybe have one your remote control,lol
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And after all of that that PSU is still great value for the money i grabbed mine for 10$ on aliexpress ,they are great for portability and cause of the all in one assembly,but at home i prefer precision and i am ready to DIY and cough up some more $ in order to get that. I totally get it why Master Denzler says he is working on a new one. It is just doesnt matches the quality of the rest of the gear
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Forgot to mentioned that i have build a few controllers myself and have confirmed all this first hand So, accuracy wise : buttons>multi-turn trimmer/potentiometer>knob potentiometers.
Buttons also can get fuck over time,but they are getting much less use because it is much harder to miss your target,in worst case it will be by a click or two,while with the knobs you will have to give it a couple of tries.