Weber Technics

Instructions

How to replace the kaman probe

Required Material :

Digital Storage Oszilloscope (DSO)

Calibrated Set of Kaman Probe

Feeler Gauge

Tweaker

Note 1 : In this procedure only the 'VG' (velocity gain) potentiometer will be adjusted.

The 'VG' is located on the velocity board.

Note 2 : Newer engrave heads have the 'VG' potentiometer on the p-card

instead on the velocity board.

Attention : Do not turn on any other potentiometers.

Just choose your engraver model and follow the steps from top.

	700 Feedback Head	700 Feedback Head	820 Vista Vision 1	820 Vista Vision 3
01
	If voltage is bigger than 0.5VDC switch off the machine anddisconnect the engrave head	If voltage is bigger than 0.5VDC switch off the machine anddisconnect the engrave head	If voltage is bigger than 0.5VDC switch off the machine anddisconnect the engrave head	If voltage is bigger than 0.5VDC switch off the machine anddisconnect the engrave head
02
		Remove kaman probe from engrave head
		Handle probe very carefully, it can break extremely quick!
		Switch on the engraver.


		Touch slightly with kaman probe tip against the aluminium surface of oscillator box.

		If probe tip is away from the aluminum the voltage should be 13VDC
		If probe tip touches the aluminium (90° angle) the voltage should be minus 2-4 VDC

		If the voltage is always around 13 VDC the probe seems to be bad. (Send to Weber Technics for replacement)

		If the voltage changes, but goes not to minus 2-4 VDC the probe is not adjusted correctly. (Send to Weber Technics for recalibration)

		Mount the tested or replaced kaman sensor to the engrave head again. Do not tighten the screw.
		Slide the kaman tip against the back of the stylus arm, until the voltmeter shows less than +/- 0.02 VDC. Tighten the screw.
		Use the feeler gauge to verify the space between the back of the stylus arm and the kaman probe. If you have no plastic feeler gauge use an edge of a business card to slide between arm and probe.
		Basically the procedure is finnished.
	If the first five engraved cells looks not even you can fine adjust the VG potentiometer at the velocity board.	If the first five engraved cells looks not even you can fine adjust the VG potentiometer at the P-Card.	If the first five engraved cells looks not even you can fine adjust the VG potentiometer at the velocity board.	If the first five engraved cells looks not even you can fine adjust the VG potentiometer at the P-Card.

	Attach the oszilloscope to 'POS' testpoint on velocity board.	Attach the oszilloscope to 'POS' testpoint on the p-card.	Attach the oszilloscope to 'POS' testpoint on velocity board.	Attach the oszilloscope to 'POS' testpoint on the p-card.
			Engrave a horizontal stripe to the cylinder with about 1-2 cm height
			Setup the oszilloscope

			Switch off the AC vibration

	Find the front end response curfe	Find the front end response curfe	Find the front end response curfe	Find the front end response curfe

				Adjust VG potentiometer

				Try to adjust 'VG' that the signal becomes the red line.
				Switch on the AC vibration again
				Frontend (first five cells) should look nice now.
				Frontend (first five cells) should look nice now.

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