*FantasticTubes !!!

*

One matched pair, circa 1950s, U.S.A made by Tung-Sol,
type 5687 vacuum tubes
as pictured.

Guarantee Good Working tubes

Silk-Screening:
nil

Acid Etched Designations (Tung-Sol's emblems):
5687 / 3
5687 / 3

Painted Designations:
nil
nil

Date Codes:
n/a
n/a

Tubes feature black plates, copper grids and top-mounted 'Horse-Shoe' shape getters construction.

Tubes appear identical in construction.

*

Hickok TV-7B/U* tested

@ 82/87     85/90

minimum acceptable value for a good tube:
38/38
(Triode#1 / Triode #2)

*Hickok TV-7B/U is a mutual conductance (Gm) type tube tester. It does check for mutual conductance which is a more accurate measure of tube's age.

Satisfaction Guaranteed!
*FantasticTubes !!!