radiomuseum.org
Please click your language flag. Bitte Sprachflagge klicken.

GR13T

GR13T; Kolster Brandes Ltd. (ID = 1411133) Radio
GR13T; Kolster Brandes Ltd. (ID = 1410967) Radio GR13T; Kolster Brandes Ltd. (ID = 1410968) Radio
GR13T; Kolster Brandes Ltd. (ID = 1410970) Radio GR13T; Kolster Brandes Ltd. (ID = 1410971) Radio
GR13T; Kolster Brandes Ltd. (ID = 1410972) Radio GR13T; Kolster Brandes Ltd. (ID = 1410973) Radio
GR13T; Kolster Brandes Ltd. (ID = 1411134) Radio GR13T; Kolster Brandes Ltd. (ID = 1411135) Radio
GR13T; Kolster Brandes Ltd. (ID = 1411136) Radio GR13T; Kolster Brandes Ltd. (ID = 1411137) Radio
Use red slider bar for more.
GR13T; Kolster Brandes Ltd. (ID = 1410967) Radio
Kolster Brandes Ltd.: GR13T [Radio] ID = 1410967 933x738
Select picture or schematic to display from thumbnails on the right and click for download.
For model GR13T, Kolster Brandes Ltd. (KB, K.B., ITT); Foots Cray; GB:
I think stripped and re-varnished by a previous owner.
 
Country:  Great Britain (UK)
Manufacturer / Brand:  Kolster Brandes Ltd. (KB, K.B., ITT); Foots Cray; GB
Year: 1951 ?? Category: Broadcast Receiver - or past WW2 Tuner
Valves / Tubes 4: 6BE6 6BA6 7C6 6G6G
Semiconductors (the count is only for transistors) 6SR7_Vibrator
schematic requested
Main principle Superheterodyne (common); ZF/IF 422 kHz; 2 AF stage(s)
Tuned circuits 6 AM circuit(s)
Wave bands Broadcast plus more than 2 Short Wave bands.
Details
Power type and voltage Storage Battery for all (e.g. for car radios and amateur radios) / 6 Volt
Loudspeaker Permanent Magnet Dynamic (PDyn) Loudspeaker (moving coil) / Ø 8 inch = 20.3 cm
Power out
from Radiomuseum.org Model: GR13T - Kolster Brandes Ltd. KB, K.B.,
Material Wooden case
Shape Tablemodel, with any shape - general.
Dimensions (WHD) 485 x 305 x 200 mm / 19.1 x 12 x 7.9 inch
Notes

Probably an export model as it's 6V DC only, no long wave and not listed in usual UK service sources.

Features

  • Aerial/Earth sockets (no built in aerial).
  • PU/Gram sockets.
  • External speaker sockets with screw switch.
  • Plessey 6SR7 6V synchronous vibrator pack (not a metal 6SR7 tube/valve) so no HT rectifier required.
  • Power cord has 10 amp fuse on side of chassis.
  • Two  scale lamps/dial bulbs.

8 Wavebands:

  • MW 185 ... 550 m
  • SW 35 ... 100 m (3 to 9.5 MHz)
  • 31m
  • 25m
  • 19m
  • 15m
  • 13m
  • 11m

The OAK V5211 6V synchronous vibrator pack (Split Reed type) appears to be identical connections to the Plessey 6SR7 unit and has required specification (100Hz, 6V, 4A input max., isolated HT reed). The separate HT "synchronous rectifier" reed is connected to the +6V input filter rather than 0V. The "snubber" network across the secondary of the transformer is critical and is 10K Ohms in series with 10nF @ 1000V. A 1500V or 2000V rated part for replacement would be reasonable. But the actual capacitor and resistor values are related to the vibrator frequency and transformer 

Total consumption is 2.3A @ 6V excluding two scale lamps / dial bulbs. The example model had 2 x 300mA bulbs but 150mA or less types (@ 7V rating) would seem reasonable.

A small "shutter" is driven across tuning scale by wave change switch to indicate selected band.

The RF/IF is similar to Kolster Brandes LR30 and the 7C6 6G6G Audio is similar to many 6V vibrator pack driven car radios, with addition of an active tone control that seems similar to some Kolster Brandes mains models (but not the LR30).

Net weight (2.2 lb = 1 kg) 6.5 kg / 14 lb 5.1 oz (14.317 lb)

Model page created by Michael Watterson. See "Data change" for further contributors.



All listed radios etc. from Kolster Brandes Ltd. (KB, K.B., ITT); Foots Cray; GB
Here you find 415 models, 367 with images and 253 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.




  
rmXorg