This record consists of 40 tubes. The 5687 is a medium-mu twin triode in a miniature nine-pin glass envelope. All but three of the tubes are manufactured by Tung-Sol; the three are made by IBM. Every tube has a red dot of paint on the top of the envelope near the tip.
Place Manufactured
U. S.
Identifying Numbers
Model number
5687
Printed in silver ink around the glass envelope.
Other number
317292
Printed in white ink around the glass envelope of 2 tubes.
Other number
3225634-3
Printed in white ink around the glass envelope of 2 tubes.
Other number
3225636-3
Printed in white ink around the glass envelope of 1 tube.
Other number
3225750-3
Printed in white ink around the glass envelope of 1 tube.
Other number
3225801-3
Printed in white ink around the glass envelope of 7 tubes.
Other number
3225923-3
Printed in white ink around the glass envelope of 1 tube.
Other number
322609-3
Printed in white ink around the glass envelope of 9 tubes.
Other number
322615-3
Printed in white ink around the glass envelope of 1 tube.
Other number
322622-3
Printed in white ink around the glass envelope of 8 tubes.
Other number
322626-3
Printed in white ink around the glass envelope of 4 tubes.
Other number
322805-3
Printed in white ink around the glass envelope of 2 tubes.
