The most common and most likely answer to this crossword clue is the 8 letter word RHEOSTAT
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More clues leading to the result RHEOSTAT
- Something affecting resistance of East German during 5
- Electrical device starts to adjust tension 19 fiddled with first
- The star beginning to oscillate could become dimmer, possibly
- It currently controls rose that is rambling
- Others upset at variable resistance
- Device in circuit, sort to melt with heat
- Those out to stop traitor that changes Resistance?
- Current monitor coming from north-east, not north
- Controller of current that rose at sea
- Short tea breaks for the current controller
Buddy explains!

The straight part
We know that "Device in circuit" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case device in circuit = rheostat.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does RHEOSTAT mean?
RHEOSTAT noun- An electrical resistor, with two terminals, whose resistance is continuously variable by moving a knob or slider.