Frequently asked questions – Techne TC-4000 User Manual
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BLOCK REMOVAL
Before removing the block, disconnect from the power supply and allow it to cool to below 50°C.
FREQUENTLY ASKED QUESTIONS
Q1 What is the 'Pause' function at the start of the program used for?
A1
Some users prefer to preheat the heated lid before placing the samples into the unit. The pause
feature is used to stop the unit after the 4 minute heated lid preheat step. It will also sound an
audible alarm indicating that the machine is ready for the sample tubes or plate to be added.
Pressing the "Pause" key followed by the "Enter" key will commence the remaining program.
Q2 Why do you have to press some keys twice to make the unit do what you want it to do?
A2
With many of the program features there is a fail-safe function which asks if you are sure you want
to perform a particular action. You are required to press one key to select a function followed by a
second to accept it.
Q3 What is 'Hot Start'?
A3
A "hot start" is used for reducing non-specific product formation during the first cycle of
amplification. The 'Hot Start' programming step is used to pause the instrument at a specific
temperature, typically around 70ºC, after the initial template denaturation. The reason is to allow
the manual addition of unmodified Taq DNA polymerase which may loose activity if added during
the initial 5min denaturation. Heat-activated Taq or Hot Start enzymes do not require this step.
Q4 What is the incremental function?
A4
Incremental timing and temperature are used to increase or decrease either the time or temperature
incrementally over the number of cycles in a stage.
●
Slide the quick release handles in the
direction of the arrows indicated and lift the
block assembly out of the unit.
●
Never lift or carry the block by one quick
release handle, always use both handles or
support the block from underneath.
●
When re-fitting the block, or fitting a new
one, slide the quick release handles in the
opposite direction to lock the assembly into
the unit.
●
Open or closed padlock symbols are printed
on the quick release handles for easy
reference.