THE GREAT MULLARD MAGIC BLOG

In January of 1948, a group of engineers at Mullard Research Laboratories, Salfords were given the brief to design and bring to production within two years (24 months), 'a valve testing apparatus suitable for use by dealers and service engineers'.  The aim was to showcase this exciting new post war development at the British Industries Fair Radio Show in late 1950 at the Castle Bromwich, Birmingham halls.   The target was met and sure enough, on Mullard's stand at Site 64, the 'valve testing apparatus' was proudly presented to the waiting market. The design brief and the problems in meeting this requirement...

Ello peeps, well, I'm back from my travels and am in a good mood so, I thought I would share this radio related radio joke with you, anyhow, here goes............ An elderly couple are listening to a preacher on their Atwater Kent breadboard radio when the preacher tells the listeners "If you need healing today, I want you to place a hand on the part of your body you need healed, then place your other hand on the radio's output valve and you will be healed!"    The old man slowly places a hand on the power output valve then  inches his other hand  firmly...

The Radio Corporation of America (RCA) was formed in 1919 by General Electric, AT & T and United Fruit with the encouragement of the US Federal Government which wanted to maintain US leadership in long distance communications.  Post war American Marconi was bought by General Electric and transferred to RCA.  General Electric and Westinghouse made RCA their exclusive marketing channel for receivers and tubes in return for cross licenses to their patents.  In 1941 RCA had decided to bring its R&D on to a single 260 acre site it purchased near Princeton University. The chosen site was close to its...

OK, previous blog entries have described the “3 Services” legacy valve numbering systems as well as the GPO numbering system and as we have seen there was little if no commonality. Something had to be done and in 1941 everyone agreed to use a common system of nomenclature known as the COMMON VALVE or CV numbering. The agreement was a bit of a compromise as it only applied to NEW valves so there would always be old system labelled valves kicking about in stores.  However, a volte-face occurred in 1943 as the Navy kicked up a fuss, so all valve...

Hi peeps, well, in response to another valve related query, this time about 'JAN codes', I thought I would pen a little information nuggett here today. I shall be doing a further more detailed blog entry on military coding history and types soon but for now here's a quick info - bite. The JAN code is of course the US Military Joint Army Navy coding introduced in 1942 in which the code for a particular valve type comprises of an alphanumeric code, for example VT-114 and additionally a three digit alpha code. I will deal with the former in more...