Click on the picture to enlarge

 
Builder Geloso
Model G185 R
Year 1960
Bands MW1-MW2-SW1-SW2-FM
Tubes ECC84-ECF80-UCH81-UF85-UABC80-UL41-UY81
Tuning Supereterodyne with MF of 455Khz and 10.7Mhz
Power 110-220 Vca
Size 55x25x35
Audio drive One UL41 power penthode
Magic eye Yes, a DM70

 
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Internal view of the chassis from the top view. You can see on the left the FM group (ECC84 & ECF80) and on the bottom right the little power autotransformer. In these cheap receivers this component was used often  in order to obtain a smaller chassis.

Rear view of this receiver. On the bottom left you can see a missing dial scale lamp. I don't know why but during the last restoration (Not made by me..) someone removed not only the lamp but the lamp holder too, cutting the wire directly inside the chassis...!!


Click on the picture to enlarge
Click on the picture to enlarge

Front view of the chassis just removed from its wood cabinet. You can note the perfect conservation state of the tuning scale with its band (AM and FM) and the four knobs. As a typical construction the left one is the ON-OFF switch and volume control. The window in the top left corner of the tuning scale is the magic eye window.

Bottom view with all the components. The MF-AF group is located in a different box on the top of the chassis, the rest of the circuit is developed under the metal ground. The big orange capacitors are the Geloso "dry" electrolitic capacitors used as anodic filtering.

Click on the picture to enlarge

Detailed view of the metal label in the bottom left of the receiver. Present in all Geloso receivers this plate was used to indicate the nominal operational voltage, the frequency usage, the model identification but more important all the tubes used in the chassis.

Enlarged view of the tuning indicator (Magic Eye) type DM70. This cheap and little tube was used to indicate the exact tuning of the choose station. The dimension of the esclamation point depens directly from the ACG voltage, so more is the power of the received station more is its lenght.



This is an enlarged picture of the tuning indicator (magic eye) type DM70. This little tube works only with four wires, and a low anodic voltage (80V about).It was used specially in many Geloso receivers and tape recorders. One of this, the Geloso G255, is part of my collection and can be found in the main collection page. The green area of this tube is the plate of the triode. Just modifying the grid voltage was possibile to obtain a greater o smaller lenght of the esclamation point, this in order to indicate the correct tuning or recording volume. Due to its high input impedance the magic eyes grid can be connected directly to the AGC circuitry without any signal loss or distortion.


 


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