antentopSince2 July

Ham Spirit
Free Choice



Free Antentop Amateur Open Book
Antentop Album
Antentop Survey




Antentop is FREE e-magazine devoted to Antennas and Amateur Radio an

Special page devoted to

Vacuum Tubes

Custom Search


ANTENTOP- 03- 2003, # 004

Vacuum Tubes


Glass valves with Loctal base - 9 pins having a lock in a metallic spigot. 1940-50's. Photo shows the Soviet 4P1L valve (in the center). In particular, such valves were used in the "Philips 208U" radio.







Glass valves with the "Rimlock" base. 8 pins, diameter 18 mm. On the tube's glass base there is a direction "nose". Photo shows 6,3 V valves of indirect heating produced by the "Philips" taken from a "Philips 320A" receiver: ECH42, EBC41, EAF42, EL41, AZ41. Valves of such a design were not made in the USSR.

Valves with the Noval base with 9 or 7 (Heptal) pins, known in the USSR as "finger-shape" valves. Diameter 18 and 16 mm. A gap in the pins located by circumference served for direction while setting the tube. They gained a wide spread in the USSR from late 1950's as substitutes for octal valves and became the last series of tubes used in home radio devices.

Page 98


92 93 94 95 96 97 98 99 100



QRP Transceivers and PA from Accessible Parts IP for QRP Antentop Book Radio Antenna Engineering Book Antentop Printed and e- magazines



Just for Fun:

Map IP Address

Thanks for your time!

Last Updated:

February 29, 2020 23:14

Antentop Home Page

Free Antentop Open Book