HT and Grid Bias

Grid Bias, "Winner" and "Portable HT" Ever Ready packs

The "Winner" and "Portable" packs date probably from mid 1920s and mid 1930s. The LT of the radio was from 2V, 4V or 6V Lead Acid Accumulator. No "Dry Cell" Radios till 1938 in USA and 1939 in UK.

These all appear to use U10 / "B size" cells. So all have about 2500mAH capacity and about 76mm height. Width and Depth are mm, sockets on top face are usually 1/8" wander plugs. All appear to be two part boxes with "tabs" folded in at short sides, so packs with unknown dimensions calculated on this basis. The Winner 9 Grid Bias pack about 72 mm high. Sockets are usually soldered direct to top caps or if required (i.e. the most negative connection) to the edge of the zinc can supported by the rim. 

Type Voltage Cells W   D kg Comment
Winner 9 9 6 x 1 127 22 0.25 Grid Bias, Every 1.5V
GB12 1 12 8 x 1 170 22 0.33 Grid Bias. tapped every 1.5V
GB15 2 15 10 x 1 202 22 0.41 Grid Bias. tapped every 1.5V
GB22.5 3 22.5 15 x 1 316 23 0.61 Grid Bias, tapped every 1.5V
Winner 60 60 8 x 5 170 106  1.63  
Winner 66 66 11 x 4  233 85 1.80  
Winner 99 99 11 x 6 233 126  2.70 taps top and bottom (every 9V)
Winner 108 108 12 x 6 254 126  2.94 taps top and bottom (every 9V)
Winner 120 4 120 10 x 8 212 168  3.27 12 , 24, 36, 48, 60, 72, 84, 96 108V
Winner 120 120 10 x 8 212 168  3.27 48, 60, 72 108V taps
Winner 120GB 111 + 9 10 x 8 212 168  3.27  
Winner 126GB 120 + 6 12 x 7 254 147 3.43  
  1. There may be an Ever Ready 12V Grid Bias pack with taps every 1.5V, certainly the Siemens 12V used in Mullard kits in 1929.
  2. There is a 15V Siemens "Full O'Power" GB pack shown in September 1931 Mullard "Radio for the Millions" issue. Also Crompton Parkinson.
  3. There is a 22.5V GB pack shown in 1930 to 1931 Mullard "Radio for the Millions" issues.
  4. Older version of Winner 120 has very many more taps.

Ever Ready Portable HT Packs

Type Voltage Total Volts Cells W D kg Comment
Portable 24 126 + 10.5 136.5 13 x 7 274 147 3.72 GB tapped, taps 3V from 63V.
Portable 30 114 + 6 120 10 x 8 212 168 3.27 6V GB
?? 2 115.5 + 10.5 126 12 x 7 254 147  3.43 GB 10.5V, tap 108V
Portable 32 166.5 + 9 175.5 13 x 9 274 186  4.78 12V taps 60 .. 162, GB 1.5V
Portable 33 120 + 9 129 11 x 8 233 168  3.59 129V
Portable 34 120 + 9 129 11 x 8 233 168  3.59 129V
Portable 40 135 + 9 144 12 x 8 254 168  3.92 4.5V, 12V taps 51:123, G 1.5 
Portable 56 126 + 10.5 136.5 13 x 7 274 147  3.72  
Portable 61 90 90 10 x 6 212 124  2.45  
Portable 75 124.5 +12 136.5 13 x 7 274 147  3.72  
  1. All Winner and Portable 2500 mAH
  2. ?? = Ever Ready designation unknown
  3. There is a Vidor 17872, tapped at least 1.5, 3, 72 &108V. Size of a Winner 108
  4. The Portable 32 and Portable 56 may be 84mm high as the base needs to be stronger.
  5. Most data is from R&TVS 1959-60 and GEC battery Shortform catalogue, some from eBay photos.  Voltages and sizes may be in error.

 

British Code for wander plugs used on Battery packs

Type Colour Comment
Highest + HT Red 45, 67, 90, 120 up to over 200V
2nd highest Yellow Typically g2 or Screen Grid
3rd " Green  
4th " Blue  
LT Positive Pink 2V, 4V, 6V till 1938
Negative Black Can be common GB+, HT-, LT-
Max GB neg. Brown Can be up to -18V
2nd GB neg. Grey typically -1.5, -3, -4.5, -6, -7.5 etc
3rd GB neg. White typically -1.5, -3, -4.5, -6, -7.5 etc
Centre tap White  
Additional Violet Two GB, every 3V from 63V

 

HT Cell packs from 1938/1939 using B size Cells

Type Voltage Cells mAH use mA W mm   H mm D mm Conn. Weight
AD2 45 30xB              
AD3 90 + 1.5 60xB, 8x              

Notes:

AD3 replaced by B103 and B130 (high capacity) packs using layer cells for HT about 1946. US Eveready (NCC) introduced "mini-max" (prismatic or  layer cells) between 1938 and 1940, the UK Ever Ready "batrymax" are the same. There was also layer version of the Winner 120 called PP120. Layer cells are twice the capacity in the same volume (and two thirds weight) as the "B"/U10 based HT packs at 10mA..