NE TEC Selectra survey meter

[pg103]

Hello,
here my NE Technology Selectra survey meter buy as defective over ebay.
I have can repair this device.
This Version is a "Selectra" for Intelligent probes connecting with the 7pin Fischer connector.
I have modified this Selectra to Electra for normal probes.
This device have DIP switches for Mode selection

Mainboard:

IMG_7728.JPG

High Voltage Board:

IMG_7733.JPG

Original Fischer connector

IMG_7734.JPG

Replaced with a 7pin Lemo connector. I have a Eberline E600 Ratemeter with a 7pin Lemo connector with some self build adaptors.

IMG_7808.JPG

With a Scionix Holland probe

IMG_7813.JPG

This device have a fast response.

[Neutrino]

Congratulations on the great repair!
Lemo connector .... perfect choice!
Selectra survey meter is very nice.
Could you write the features of the device?

[pg103]

Hello Neutrino,

thanks!

There are different models:
ELECTRAGMPLUS1B: internal Geiger Tube, Data storage and com port , MHV connector
ELECTRAPLUS1B: Data storage and com port, MHV connector
ELECTRA1A: PET probe connector
ELECTRA1B: MHV connector
ELECTRAGM1A: PET connector, internal Geiger Tube
ELECTRAGM1B: MHV connector, internal Geiger Tube

The Selectra Models have a 7pin Fischer connector for smart probes

Specs:
Nominal Range 400 V - 1400 V in 5 V steps
Absolute value ± 2.5 V
Maximum Load 66 MΩ + 10 μA @ 1400 V 40 μA @ 900 V

Charge Sensitivity
Lower Threshold - 1.7 x 10
-11 C (100 mV) ± 1% (FIXED)
Upper Threshold - 2.6 x 10
-11 C to 5.1 x 10-10 C
(150 mV to 3.00 V in 50 mV steps)
Accuracy: ± 1% or ± 15 mV which ever is the least.

Overload protection
Presettable overload protection based on
excess current from the High Voltage supply.
Nominal Range 0.00 μA to 44.50 μA in 0.25 μ
A steps (range dependent on probe type).

Dead time correction
Presettable value for dead time correction.
Range 0μs (OFF) to 250μs in 1μs steps.
(Internal Geiger default 78 μs
Battery Life: 90 hr. typical, with dry cells and power saver feature (auto switch-off)
Function:
AUTOMATIC RESPONSE MODE
INTEGER GEIGER ONLY
PRESET RESPONSE MODE
INTEGRATE MODE
Presettable alpha and beta settings with dual probes
Alarm
Alarm level - presettable over defined ranges or OFF

UNIT OF MEASUREMENT
Countrate Monitoring: cps, cpm, kcps, kcpm
Contamination Monitoring: Bq, dpm (disintegrations per minute), Bq/cm2 with prefixes of k.
Radiation Measurement: R/h, Sv/h or Gy/h with prefixes of n, μ, m, k.

here the full specs:

selectra electra.pdf

here is a manual for this device uploaded from user "marconmeteo":
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here the service manual uploaded from user "marconmeteo"
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[marconmeteo]

Hi pg103, this is a very nice instrument. Many compliments for your repair/modified this.
Lemo connector have high cost but is excellent choice.