FLASHER UNIT TYPE B
Note: Not Lightning
LEADING PARTICULARS
| Stores Ref. No.: | 5CZ/6796 |
| Manufacturer: | Specto |
| Connection: | 104 Pattern / Plessey Mk. 4, small body 3-way |
| Attachment: | 3.11 in. square flange |
DESCRIPTION
The flasher unit Type B is of the same form and fit as the flasher unit Type A, however, function is slightly different: I have found it to switch to earth (current sinking) rather than the positive supply (current sourcing) as per the Type A.
EXAMPLE
Flasher unit Type B, new old stock, in original "primary standard packaging".
Experiment No.1
This unit was packed in 1966, opened 57 years later in 2023, and worked first time with no issues!
I dont' have the documentation for the Type B, but as stated in paragraph 5 of AP4343C, Volume 1, Section 3, Chapter 86, A.L.97, Feb. 1957, Flasher Unit, Type A, it can be seen in the video that the lamp temporarily illuminates when power is applied to the flasher unit, before the 50% duty cycle square wave starts.
REFERENCES
Flasher unit Type A, general and technical information:
AP4343C, Volume 1, Section 3, Chapter 86, A.L.97, Feb. 1957, Flasher Unit, Type A