The Model 917 is ideal for a smaller hospital that needs a Doppler for use in obstetrics as well as a doppler for difficult blood pressure measurements or for vascular screening. The nominal 2 MHz* probe gives depth for big targets, like the fetal heart, and also picks up the relatively large amount of umbilical flow.
A headphone jack for hi-fi headphones is provided because in difficult cases where it is important to know if there is a viable fetus, you will hear much better with big, bulky headphones than with a speaker. The big headphones shut out outside noise and reproduce the low tones associated with the fetal heart movement much better than the small loudspeaker does. Headphones of this type can be purchased from us or obtained locally. Near term, the reflected signals are so big that the use of headphones is not necessary.
The 8 MHz* probe emits ultrasound waves that are smaller and therefore reflect off of red blood cells better. These waves do not go deep enough to be useful in obstetrics.
The Model 917 is essentially two different doppler instruments using a common power source and audio amplifier. For sensitivity, each one is as good as any you can find at any price. Only one doppler operates at a time.
Model 917 comes with one obstetrical probe and one 8 MHz probe in the style of your choice. Most users buy the pencil probe (shown) but the adult flat and infant flat probes are available as a substitute or at extra cost if you require more than one vascular probe.
The custom case is made of welded aluminum and is both rugged and attractive. Colors available are black, white or blue. The lid detaches easily.
* A 2 MHz probe crystal vibrates at about 2 million times a second, and the 8 MHz probe vibrates at 8 million times a second.