MR diode - half symbol

[Nickthedentist]

Similar to the symbol for a "Shockley diode":
https://en.wikipedia.org/wiki/Shockley_diode

But I suspect that's a red herring!

[Nickthedentist]

All you could want to know about current diode symbols here: https://www.electricaltechnology.org...es-Symbols.png

[kalee20]

Practical Wireless used the half-arrow, such as in this circuit diagram from Jan 1959 (the detector diode is germanium, the power rectifier selenium - no distinction in the symbol).

I use the half-arrow myself to this day...

[ScottBouch]

Here's an example from an RAF instrument trade training manual, AP3280B, Section 1, Chapter 5, from 1964.

This chapter on electronics uses the half arrow throughout.

But another similar training manual from 1970 uses the full arrow for diodes.

[pmmunro]

Originally Posted by Nickthedentist

All you could want to know about current diode symbols here: https://www.electricaltechnology.org...es-Symbols.png

There are some symbols here that I've never seen before, some of them quite imaginative. I think if I used some of those, I would put a note alongside on the circuit diagram.

The old BS 3939 was quite informative if honoured more in the breach than the observance, but then it was split into several parts and based on an advanced "modular" symbol concept which was probably very elegant in concept but challenging to use.

However the present pricing policy makes the use of British Standards somewhat academic for many people (even academic institutions which once held complete sets).

PMM

[G6Tanuki]

Originally Posted by ScottBouch

Interesting to note they also are shown with the half symbol too!

Maybe it was an Air Ministry thing? Was the R4187 mady by Plessey, if so, maybe it was a Plessey thing?

No, the 4187 and its transmitter buddy [4188] and the rest of the V-bomber radio installation was made by STC [Standard Radio].

I suspect it was a Ministry of Defence thing, as the drawn block-diagrams/schematics/circuits all have the same style as EMERs and the like from the 'fifties, down to the letters/numbers along the sides by which components are located in the parts-list.

[ScottBouch]

Originally Posted by G6Tanuki

...the 4187 and its transmitter buddy [4188] and the rest of the V-bomber radio installation was made by STC [Standard Radio].

That's really interesting, I have just read up on those HF units.

I have the comms radios ARC-52 (UHF) used on the Vulcan B1/B1A, and PTR-175 (UHF and VHF) used on the B2. these radios would be used for air/air comms and air traffic control, airfields, tower, etc... but what would the HF radios be used for? To talk to ships maybe?

I believe the ARC-52 (UHF only) was a Collins design, but produced in the UK by Plessey, then was developed into the PTR-175 (UHF & VHF), and PTR-177 (UHF, VHF & Data Link [Link 4]).

The STC kit resembles in appearance of its features, the ILS kit also made by STC.

Cheers, Scott (digressing off topic)

[G6Tanuki]

Originally Posted by ScottBouch

That's really interesting, I have just read up on those HF units.

I have the comms radios ARC-52 (UHF) used on the Vulcan B1/B1A, and PTR-175 (UHF and VHF) used on the B2. these radios would be used for air/air comms and air traffic control, airfields, tower, etc... but what would the HF radios be used for? To talk to ships maybe?

I believe the ARC-52 (UHF only) was a Collins design, but produced in the UK by Plessey, then was developed into the PTR-175 (UHF & VHF), and PTR-177 (UHF, VHF & Data Link [Link 4]).

The STC kit resembles in appearance of its features, the ILS kit also made by STC.

Cheers, Scott (digressing off topic)

The STC radios were used for long-range ground-to-air comms; only HF radio could get transcontinetal coverage [as needed if you were flying from the UK to bomb Moscow, or - as was the case in the 1980s - reach the Falklands]

[Cobaltblue]

Can we get back on topic please.

Cheers

Mike T

[G6Tanuki]

Originally Posted by Cobaltblue

Can we get back on topic please.

Sorry...

[m0cemdave]

My copy of BS530:1948 "Graphical Symbols for Telecommunications" gives both symbols for rectifiers - the half arrow described as preferred and the full arrow as alternative.

A stuck-on addendum note (undated) states that the full arrow "should be used for designating a signal rectifier, where it is necessary to distinguish between signal rectifiers and others"

Supplement No.7 (1962) "Symbols for Semiconductor Devices" updates this to use the full arrow only.

[ScottBouch]

Originally Posted by m0cemdave

My copy of BS530:1948 "Graphical Symbols for Telecommunications" gives both symbols for rectifiers - the half arrow described as preferred and the full arrow as alternative.

A stuck-on addendum note (undated) states that the full arrow "should be used for designating a signal rectifier, where it is necessary to distinguish between signal rectifiers and others"

Supplement No.7 (1962) "Symbols for Semiconductor Devices" updates this to use the full arrow only.

Good work!!! Problem solved!

Brilliant detectorist effort there, and lucky that you have copies of the standard!!!

Many thanks, Scott.