Emerson Wondergram.
Portable battery
Turntable. Produced
from 1960 to 1965 by "Baird", England. Allows you to
listen to records at speeds of 33 and 45 rpm. Dimensions
220 x 110 x 50 mm Weight without batteries 850 g,
nutrition 6 v, the four-cell battery C. Structurally,
the apparatus is designed as a bakelite case, in which
the top is inserted a metal deck, which is mounted all
the mechanics and electronics. Lattice dynamics is below,
and for better hearing on the case, there are three
Turndown legs. Mechanics fairly tech and high quality.
The design uses molded components. When you open the lid lock
tonearm is released, and it rear
its on deck with a special spring mechanism. To activate
electrophonic should simply withdraw the tonearm from the
starting position to the side. Circuit collected on the three
germanium transistors type GET114 (1 pc.) And S1 (2 pcs.)
Manufactured by General Electric Company, and two
transformers. There is
volume control. Pickup piezoceramic has two needles.
Inserting a pickup in the holder properly, you can
choose what kind of needle to use. The plate is
installed on a freely rotating stand, not connected with
the engine. Rotation of the plate by means of two
rollers protruding from the deck at different distances
from the center. These rollers protrude from the deck at
different heights. Thus, if you have disc "45s"
small diameter, it rotates the roller is located closer
to the center at a speed of 45 rpm. If a disc of large
diameter, it rotates a distant spot, rising from the
deck to a higher altitude than the closest. In this case,
the disc rotates at a speed of 33 rpm. Also on deck and
on the lid are supporting rollers that keep the disc
rotating in the correct position. To play "45s"
having a large diameter hole nozzle provides for the
storage of which is a special place on the inside of the
lid, beside with the auxiliary roller. In the closed
position the cover captures the latch with a button.
The device was bought complete with a leather cover, in good cosmetic
condition, but a failure. Mechanics was in order, all
the commercials intact, and required only the
replacement of lubricant. Electronics not working, and
needed replacement of all three electrolytes, and repair
of AC resistance of the volume. The design of the
variable resistor is not provided for repair, but was no alternative, had to
file down the rivet on both sides, restore contact
engine and fasten all screws. At present, the unit is in
working condition. The sound quality is decent, I
assumed that would be much worse. Volume also missing.
Demovideo
Photos can be enlarged
During the renovation had to replace all the
electrolytic capacitors. To retain the original form
design, I made out the old capacitors, removed the
aluminum liner interior, and put them in the new
capacitors are suitable denomination and size. After
assembling the capacitors were obtained very similar to
the original.
On the left the original capacitors.
Right - the new ones.
In the photo below - resistor, which
had to be repaired
Schematic diagram Emerson
Vondergram
Emerson Wondergram Advertising in the
magazine "Electronics Illustrated" №2 of 1959.
