6146W JAN Phillips ECG Vacuum Tube (aka 7212), MATCHED PAIR, Hickok Tested

This is a Phillips ECG tube, a 6146W. 

Phillips ECG was previously known as Sylvania GTE, and before that, just plain Sylvania.

The W means it is the rugged version of a 6146.  It's also the same as a 7212. 

It's a JAN tube, which means Joint Army Navy.  JAN tubes are known for their ability to stand up to harsher than usual treatment.

A "matched pair" means the mutual conductance of one tube is within 10% of the other tube. 

Tested on Hickok 533A, Gm recorded on side of the tube box.

Photos are of one example of the available matched pairs.  It may or may not be the same tube you receive.  

• Black plates. 
• Print may be green or blue.  
• Dual halo getters.
• Made in USA.
• Ships quickly and safely from Mississippi.