Hookup wire colour conventions?

[kevingtonbeare]

Hi guys,

Are there any recognised conventions for the hookup wire colours in valve sets? E.g. red for HT, orange? for screen supplies, brown for mains active, blue for mains neutral, green/yellow for ground?

Any suggestions would be most welcome.

Thanks

Kevington Beare

[newlite4]

In addition to the colours that you mention which make good sense, I use white for input (say, around the tuned circuit) and yellow for output (for example connections to and from the output transformer).
Neil

[Sideband]

Originally Posted by kevingtonbeare

Hi guys,

Are there any recognised conventions for the hookup wire colours in valve sets? E.g. red for HT, orange? for screen supplies, brown for mains active, blue for mains neutral, green/yellow for ground

Kevington Beare

The memory is a bit hazy but I think yellow was decoupled HT, Orange for screen feed, Red for HT (unsmoothed) green for earth and I think blue was used for the connection from output transformer primary to anode of output valve. Anyone else out there with a better memory than me? (nearly everyone)!!


Rich.

[Ed_Dinning]

Hi Gents, try some of the FJ Camm books (PW servicing manual etc) they had a list in the back of standard (UK) colours that covered a wide variety of circuits, including battery sets. Perhaps this would be worth publishing on the forum in the "front pages" beside links etc. If no-one can fins anything PM me and I'll see what can be found when I'm home again at the weekend.

ED

[GMB]

I'm astonished that there is a convention at all.
I thought the idea was to either use the same colour for everything or else to try to make wires change colour as they go, especially where they go though a hole in a panel, or with the application of coloured dirt. Anything else would just make servicing too easy.

[pmmunro]

There was a standard: BS 2311, 1955 (now withdrawn).

From my BBC Fundamentals course (TA21B, 1965) notes the significant part of this standard is:

Valve Electrodes:

Anode Blue
Cathode Yellow
Control Grid Green
Screen Grid Orange

Suppressor Grid
or modulator grid Grey

Heaters Brown

DC Supplies

Chassis Black
Positive to chassis Red
Negative to chassis Violet


Miscellaneous Wiring, not part of any valve electrode or supply circuit, White or Mauve.

AC Supplies [No longer advisable for new use], modern equivalents in brackets)

Single phase line Red (Brown)
Neutral Black (Blue)
Earth Green (Green Yellow)

Three phase
Line Red (Brown)
White (Black)
Blue (Grey)
Black (Blue)

If I remember correctly this convention was followed by PYE TVT except that supplies negative to chassis were sometimes blue. I believe that PYE also used colours derived from these for transistors so that emitters were yellow, bases green and collectors blue, both for PNP and NPN transistors.

This code was certainly not used by all manufacturers of either domestic or broadcast equipment, for example Marconi had a phase when some of their television camers used pink wiring throughout with yellow marker sleeves at the ends, all neatly laced with round, black coated lacing cord.

[kevingtonbeare]

Thanks for this very helpful reply.

Kevington

[Mike Phelan]

Originally Posted by pmmunro

There was a standard: BS 2311, 1955 (now withdrawn).

From my BBC Fundamentals course (TA21B, 1965) notes the significant part of this standard is:

Valve Electrodes:

Anode Blue
Cathode Yellow
Control Grid Green
Screen Grid Orange
Heaters Brown

The 1936 Fergie I am restoring supports all these colours, except that the original top-cap leads to the RF amp and mixer from the tuning gang are red!