Electromechanical Plant of Radio Engineering and Makhachkala Electromechanical Plant. The head was very popular
among Soviet recording enthusiasts. They were put into such
players as Estonia, Radiotehnika, Electronics, Aria,
electric playing devices 0-EPU-82C, 0-EPU-82K
and many other Soviet-made vinyl disc players of the first and highest complexity class.
They differed in the quality of manufacture: the highest class GZM-005 and the first class GZM-105.
To sort by class, parameters such as
frequency range unevenness and separation between channels were measured. The frequency range itself was
given based on the class tolerances – in fact, it
is the same for both classes. The head housings are slightly different, and the replacement inserts (needles) were
exactly the same.
Over time, it became necessary to use a special holder for
installations in the tonearm, so the letter D. D appeared in the name – this is the type
of attachment. (plastic quick-release connector) for installation on
2EPU-65CM and 1EPU-73C. On 0EPU-82C and 0EPU-82K, the heads were attached with screws
without a plastic connector.A
completely different head of GZKU-631R (corundum) or GZKU-631RA (diamond) was used for Class II players.
The appearance of a new generation of turntables necessitated a change in GOST for the production of pickup heads. The requirements for the Higher (zero) class have become
somewhat higher, and some previously produced heads
have moved down a step in their characteristics. For example, GZM-005 automatically
became GZM-105, and GZM-105 – GZM-205. That is, the head of GZM-005
(old)=GZM-105 (new).
From the very beginning to the end of the production of the heads of the GZM-x05 series, a spherical diamond
needle A18/0.8 with a radius of 0.018 microns and a length of 0.8 microns was used in all inserts (GOST 7765-70). Imported
diamond needles were placed in the heads of the GZM-x55 series, and needles of domestic manufacturers were used in the GZM-x05 series.
Electrical connection of the head:
Right channel: Left channel:
Housing-Green
Housing-Blue
Signal-Red
Signal-White
