Instructions and Users Manual
for all Models
SV, SV 2.25, CV, CV 2.25, and CVA

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1. Warnings 9. Shipping instructions
2. Use with Total Energy Probes 10. Installation Diagram
3. Capacity 11. Notes
4. Use with a Sage Total Energy System 12. Mounting Template 3 1/8
5. Adjusting Zero 13. Mounting Template 2.25 Size
6. Modifying Case 14. Conversion Table
7. Leak Testing 15. Audio Variometer Instructions
8. Additional Warnings  


Congratulations, you have purchased what we believe to be the finest mechanical variometer in the world. Pilots have enjoyed this fine handmade variometer for over twenty years with many of those first instruments still in use today! We hope you enjoy this variometer for many years into the future. If you have any questions, please don't hesitate to contact us.



Model CVA Model CV Model SV
Model CV2.25 Model SV2.25



Many variometers are damaged by Manually sucking or blowing into the ports of the variometer By far, the greatest risk period occurs between the time the variometer is received until after it is installed. During this time the temptation to blow into the instrument is seemingly irresistible. Manually sucking or blowing into the ports of the variometer is almost certain to damage the variometer. Beware of everyone.



When using the Sage variometer with a total energy probe, place one or more of the enclosed pneumatic restrictors in series between the static port on the variometer (marked "S", see #10) and the total energy probe. This is to reduce the jumpiness caused by the noisy signal generated by the total energy probe. The two hole probe is generally believed to be the best.



The capacity of the bottle should be 0.45 liter (1 US pint) and connected to the capacity port on the variometer (marked "C", see #10). The performance of the system will be modestly improved by placing a thermal heat sink into the capacity (three copper wool sponges obtainable in grocery stores. In years past these were called Chore Girls and are now named Chore Boys.) Insulation of the capacity is of great importance poorly insulated capacities have been the cause of many problems, also avoid placing the capacity near the underside of glare-shields as these have been shown to be sources of heat that affect the capacity and variometer system.



When using the Sage variometer with a Sage total energy system, the pneumatic resistor supplied must not be used. If the resistor is on the vario, removal is most easily done by slitting the tubing with a knife or razor blade. The variometer can then be installed according to the instructions supplied with the total energy system.



The plastic plug which seals the hole in the center of the faceplate is a blind nut combined with a o-ring and screw. Usually the plug can be removed by gripping the small flange at the base of the plug with the fingernails and pulling the plug straight out of the faceplate. If this technique is inadequate then a screw driver should be used to turn the plug counterclockwise several turns. This should loosen the plug and allow it to be removed from the faceplate. The plug should be a snug fit in the hole and this can be achieved by adjusting the compression of the o-ring with the screw. A very small amount of silicone grease on the o-ring will improve insertion and sealing. By removing the plastic plug in the front of the instrument it is possible to readjust the zero of the instrument with a small screwdriver. However, if the zero is displaced because of damage to the variometer, then the mechanical stops which help protect the instrument from damage during extreme overrangeing, will likely become effective prior to the needle reaching full scale. This will cause the variometer to read somewhat less than the actual climb or descent rate. The variometer will be fully functional otherwise and can be used until it can be returned to me for servicing. Do not remove the plug during flight as this may damage the instrument, any adjustments should be done on the ground.



It seems that modifications to the variometer case are often necessary. I suggest these be accomplished with rough sandpaper and a block to minimize stress on the case and variometer movement. Excessive pressure applied to the mounting flange by over tightening mounting screws can cause a serious leak to develop in the variometer case because of the close proximity of the mounting flange to the bond between the glass faceplate and epoxy case. The use of the plastic mounting screws supplied with the variometer will prevent this problem. These screws are rated for 120 g's vertically and 340 g's longitudinally and are therefore suitable for use in this application. Use of metal mounting screws is not advisable, but if used they should not be made tighter than just barely snug.



One of the most important things for proper performance of a variometer is to ensure that there are no leaks in the system by this I mean the line to the total energy probe and the line to the capacity must not leak. The procedure to check these lines is fairly straight forward and requires only a few components first you will need to locate a method to pressurize the lines, one or two large bore syringes work well, in addition you will need some tubing of different diameters to connect to the total energy port in the tail and a "T" connector. The first step will be to label all the tubes at the instruments to get things back in the proper places when we are finished, second we will remove the total energy line and attach it to the air speed indicator this will be used as our pressure indicator now we will hook up the syringes to the total energy probe port on the tail and pressurize the system while carefully watching the airspeed indicator there is no need to exceed a reading of 50-60 knots a perfectly sealed system would hold this reading indefinitely however this is not usually the case but it should take several minutes for the reading to drop to zero. This procedure can be used for other systems on the glider Use great care to avoid large pressure changes assure that the airspeed indicator reads zero before removing any of the lines Repeat this procedure with the capacity line using the "T" connector with the syringe between the capacity and the airspeed indicator . While the Sage variometer is more rugged than other mechanical variometers in most ways, it is more sensitive to large pressure surges. The only area where this presents a problem is when performing leak checks of the instrumentation system. I suggest that all checking be done initially with the Sage variometer removed from the system. After reinstalling the variometer, be extremely careful to assure that no inadvertent sudden pressure changes occur during subsequent testing. All increases and decreases in the pitot, static, or total energy probe pressures should be monitored by watching the variometer to insure that the needle never indicates more than 5 m/s (10 knots) at any time. Manually sucking or blowing into the ports of the variometer is almost certain to damage the variometer.



After installation there have been a couple of instances of people blowing into pitot tubes when ships were left unattended in hangers or out on the field. A number of variometers have been damaged by transporting them with the two ports connected together with a piece of tubing. Removal of the tubing can cause a sudden pressure transient within the variometer either because of an altitude or temperature change during transportation. Taping and untaping static ports can cause a similar problem. Either of these practices can cause the variometer to experience pressure signals corresponding to hundreds of times normal full scale reading, and the device will not survive intact. Shipping and storing in a sealed plastic bag can also damage the variometer because of the rapid pressure fluctuations which can be generated by squeezing the bag. Several variometers have been destroyed by the application of 100 psi shop air during attempts to remove water or dust from static or pilot lines. One variometer was damaged in a terminal velocity dive with the dive brakes out. the descent rate was a sustained 110 knots straight down.



If return for repair should be necessary, the variometer should be placed in a box surrounded by a minimum of two inches of packing material. The ports should be left open and the variometer should not be placed in a plastic bag.

  Returning for service
It is important when returning for service that the instrument be properly protected to prevent further damage and documented to help speed the repair process.

  1. The instrument should have at least one inch of padding on all sides two inches is recommended it can be placed directly into foam peanuts if it is packed tightly to prevent settling DO NOT PLACE IN A PLASTIC BAG.
  2. Include a return address, name, phone number, email and the problem with the instrument. This is important to help speed the repair. (pdf form to print & fill out)
  3. The average price for most service is around $400 plus shipping and handling.
  4. Ship or Mail to SAGE Variometers, 2668 Husted Road, Williams, CA 95987 USA
  5. Please be sure to indicate "Civil Aircraft Parts returned for Repair" on any shipping documents to avoid unnecessary customs fees.



11. NOTES:











Check for proper scale

3 1/8 SIZE



Check for proper scale

2.25 SIZE



Length Area
1 mm = 0.03937 in.
1 cm = 0.3937 in.
1 m = 3.2808 ft.
1 m = 1.0936 yd.
1 km = 0.6214 mile
1 km = 0.5396 nm
1 in. = 25.4 mm
1 in. = 2.54 cm
1 ft. = 304.8 mm
1 yd. = 0.9144 m
1 mile = 1.6093 km
1 n.mile= 1.85 km
1 mm2 = 0.0015
1 cm2 = 0.1550
1 m2 = 10.7639 sq.ft.
1 m2 = 1.3079 sq.yd.
1 = 645.16 mm2
1 = 6.4516 cm2
1 sq.ft. = 929.03 cm2
1 sq.yd. = 0.8361 m2
Volume Capacity
1cm3 = 0.0610
1 m3 = 35.3157 cu.ft.
1 m3 = 1.3079 cu.yd.
1 = 16.3866 cm3
1 cu.ft = 0.028 m3
1 cu.yd. = 0.7646 m3
1 L = 0.2200
1 L = 0.2642 US gal.
1 L = 2.2222 pint
1 = 4.5461 L
1 US gal. = 3.785 L
1 pint = .45 L
Mass Speed
1 g = 0.0353 oz.
1 kg = 2.2046 lb.
1 oz. = 28.3495 g
1 lb. = 0.4536 kg
1 m/s = 1.944 kn
1 km/h = 0.5936 kn
1 km/h = 0.6211 mph
1 kn = 0.514 m/s
1 kn = 1.853 km/h
1 mph = 1.61 km/h



Sage Installation Instructions:
Red wire - 12 volt positive
Black wire - negative / ground
Attach 9 pin plug to back of  vario being sure to tighten screws to secure plug to socket.
Install On & Off rotary volume switch in a convenient location and use supplied wrench to secure knob and push in end plug.

Rotary switch selector functions: (located on board inside rear case under USA sticker)

To configure audio fuctions, set rotary switch to desired number then press and hold red button for 5 seconds and release. 

Each 5 second cycle will cause a change in the configuration. For example, if you wish to change the audio tone, turn the selector to 7 and press the red button for 5 seconds and release. The audio tone will change to one of the 3 tones available. There is no reset to default settings. It is possible to loose track of what configuration you have set. It is reccommended that you record each configuration change you make.

Configuration switch settings:
2 - set deadband (upper and lower =0)
3 - add 0.5 kts to upper deadband (more lag off 0 climb side)
4- subtract 0.5 kts from upper deadband (less lag off 0 climb side)
5- subtract 0.5 kts from lower deadband (less lag off 0 sink side)
6- add 0.5 kts to lower deadband (more lag off 0 sink side)
7- audio tone selection



Sage Variometers, 2668 Husted Road, Williams, CA 95987, Phone:(530)473-5600


For more information:
     Office  : (530) 473-5600
     E-mail :

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