Mark 24 TQCMTM Sensor
The Smallest TQCM
in the Industry
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The Mark 24 Thermoelectric Quartz
Crystal Microbalance (MK24 TQCMTM) is fast
becoming the new industry standard TQCM,
replacing it's larger predecessor, the
MK10 TQCM.
By cooling the 3, 5, 10, 15, 25 or
50MHz quartz crystals, measurements can
be made of the mass flow as it intercepts
and is condensed at a specific
temperature.
Like all TQCMs, the MK24 can be cooled
by its own internal thermoelectric
Peltier element without any external
refrigerant, with a delta T of > 64ºC
when the heat sink is at ambient
temperature. Because it is so
small, light and less demanding of power
(only 1.44W), the MK24 TQCM is especially
well adapted to use on satellites.
Just like the MK10 TQCM, if the MK24
is actually cooled externally at its heat
sink plane of attachment, the lowest
temperature at which it can operate is
lowered to approximately -200ºC.
The size comparison chart below, shows
how the TQCMs have changed over the
years. The TQCM on the far right is
the established industry standard
MK10. Next to it, in the middle of
the drawing is the MK20 TQCM. On
the far left is the new MK24 TQCM.
| Specifications |
| Crystal
Frequency |
Mass
Sensitivity
(Hz/gm/cm2) |
Dynamic
Range
(gm) |
10 MHz
15 MHz
25 MHz
50 MHz |
2.26 x 108
(Hz/gm)cm2
5.09 x 108 (Hz/gm)cm2
1.41 x 109 (Hz/gm)cm2
5.66 x 109 (Hz/gm)cm2 |
4.45 x 10-5
gm
2.97 x 10-5 gm
1.78 x 10-5 gm
8.9 x 10-6 gm |
Dimensions:
|
Body
Heat Sink |
12.16mm Ø
(0.499")
14.96mm Long (0.589")
18.90mm Ø (0.744")
2.95mm Thick (0.116") |
| Sensor
Output |
1 to ~250 KHz |
|
| Supply
Voltage |
8 to 12
VDC (10 VDC Nominal) |
| Power |
~120 mW @
10 VDC |
| Peltier
Heat Load |
1.44 W |
| Signal
Amplitude |
>6 to
10 Vp-p |
| Voltage
Sensitivity |
<23
Hz/V |
| Output
Impedance |
12K OHMS |
| Pressure |
Ambient to Hard
Vacuum |
| Temperature
Range |
-199 to
100°C - Passive Mode
-25 to 100°C - Active Mode |
| Weight |
8.5 gm |
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