Home | Links | Contact |

Printed from www.nzmeccano.com

Top Home Bottom

Meccano Radio

(Author: Barry Gerdes)

The Meccano Radios

The Meccano radio was first released about Sept 1922 and was advertised in the Meccano magazine of that date. It had a variable capacitor made from 15 P/No 76 plates for tuning and some special insulating parts. The tuning flat coils were wound on slotted insulating material. One coil was the main resonator and the other was the aerial coupling coil that could be adjusted to improve selectivity at the expense of volume. The crystal detector was the open type still available in the 1950’s and used a spring wire “cats whisker” to contact a sensitive point on the galena crystal (lead sulphide). The headphone was a standard telephone earpiece with a reasonably high impedance to reduce loading and make maximum use of the available signal. The set sold for the princely sum of 55/-. A lot of money in 1922. A licence was also required at an additional cost of 10/-

For some reason not explained anywhere it did not meet the approval of the authorities and was withdrawn almost immediately. In October of 1922 a much simpler version was released to get around the problem. This was now called Meccano Radio No1. This set sold also for 55/-. It was far more primitive than the original version. The main coil was now wound on an insulated former about 3” in diameter and tuning was effected by a sliding tap on the main coil. However the crystal detector was now the enclosed type also still available in the 1950’s. Of note was the use of brackets P/No 108 with one side folded over at 90 degrees to hold the sliding contact arrangement. This part was later released as P/No 139 and 139a in 1923.

In May 1923 the original radio was released again as No 2 radio followed by a construction article in June 1923. This version required a special experimenters licence at 15/-. In 1924 a later improved version of Meccano Radio No 1 was released. It now was reconnected with two sliders. One for tuning and one for aerial coupling. The price had now dropped to 29/- for the No1 set and 25/- for a set of parts to build the No 2 set.

The simple open crystal set, as both of these designs were was the way most radio hams and constructors began their hobby right up to the 1970’s. By this time the basic crystal set was taken over by more effective simple radios at a far cheaper price and are now just a novelty item. They still can be made and operated but will no longer be feasible when the change to digital radio is effected.

During world war II. Crystal sets were made by prisoners of war in camps particularly Changi out of a range of odd materials. It was found that quite good detectors could be made with a safety pin and a “Blue Gilette” razor blade.

Construction

For anyone contemplating making a replica. The cylindrical coils need about 70 turns of 18G enameled copper wire on a 3” diameter plastic tube (downpipe). The flat type have about the same number of turns on a 3.5” disk with five or seven radial slots to wind the wire on.

The crystal can be replaced by a solid state germanium diode or you can make an open detector with a piece of springy copper wire sharpened to a point and a galena crystal made from lead and sulphur with suitable holders. I made galena crystals by melting about a cc of lead in a teaspoon over a candle. When the lead was nice and liquid I dropped a similar amount of sulphur into it. There was a blue flash and I was left with a congealed mass of galena that worked great as a crystal. The teaspoon never stirred another cup of tea!

The headphone needs to be the high impedance type and you will need a long aerial wire and good ground.

Meccano Magazine references
Page 6 Sept 1922 First reference to the Meccano radio
Page 6 Nov 1922 First reference to the new Meccano Radio (No1)
Page 1 Dec 1922 Full description of the new version of the Meccano Radio
Page 6 May 1923 Release of Meccano Radio No2
Page 6 June 1923 Construction details for Meccano Radio No 2 (re done 1st ver)
Page 148 Nov 1923 Advertisement for some accessories .1st appearance of Ad
Page 128 May 1924 Small reference to the improved No1 receiver with photo.

Barry

 


 

Total number of messages on this page: 15.  This is page 1 of 3.   Next

frxnzv      (at 4:34am, Mon 17th Dec, 12)

pa73PK qidozsckatge

lqdsublwirz      (at 12:07am, Thu 13th Dec, 12)

IN9wPY nsmaqxtjmchf

lqdsublwirz      (at 12:05am, Thu 13th Dec, 12)

IN9wPY nsmaqxtjmchf

jmheskreoe      (at 12:04am, Thu 13th Dec, 12)

zkgokt iirnydsrsrlq

Rosines      (at 9:20pm, Wed 12th Dec, 12)

Pretty component to coetnnt. I simply stumbled upon your website and in accession capital to assert that I acquire actually enjoyed account your blog posts. Any way I'll be subscribing for your augment or even I success you get right of entry to consistently rapidly.

kbisset      (at 8:03pm, Sat 26th Nov, 11)

My copy of Love and Gamble has emerged from the boxes. On page 87 is a discussion of Frank Hornby's visit to the US and Canada, and his interest in the new US radio. The discussion continues to explain the first British Meccano radio, but only shows the (apparently) second version, according to Barry's presentation.


Your name:
Your message:
Security check: (Please type in the text to prove you're a person!)
 
Login status:  You have not yet entered your user name and password. You cannot create or edit documents until you do.
Enter your user name and password to log in

Remember me

If you click on the box marked 'remember me next time', you will not have to log in again on this computer for three months.

If you don't have a user name yet, please click here

Latest documents:

 
(Neil Bedford and Richard Smith)
Midlands Meccano Guild
Model Report 
97th Meeting 
 
The Arduino Sketch 
and how to upload a Youtube or Vimeo video to the Gallery 
(Paulo Kroeff de Souza)
"Homemade" Screwed Rods
 
(Paulo Kroeff de Souza)
The Meccano driving band problem
 
(Paulo Kroeff de Souza)
Meccano Cord Reproduction
 
(Paulo Kroeff de Souza)
Substitutes for parts 142 and 155
 
(Philip Drew & Richard Smith)
Midlands Meccano Guild
105th Model Report 
92nd Model Report 
(Neil Bedford and John Rogers)
Midlands Meccano Guild
104th Model Report 
91st Model Report 
 
103rd Meeting Model Report 
by Peter Stuart, Meccano Modellers Association Sydney Inc 
(Richard Smith and Neil Bedford)
Midlands Meccano Guild
102nd Meeting Model Report 
(John Rogers & Colin Bull)
Midlands Meccano Guild
101st Meeting Model Report 
Spanner Challenge 
(John Rogers and Neil Bedford)
Midlands Meccano Guild
100th Meeting Model Report 
 
A G gauge model 
(Colin Bull & Richard Smith)
Midlands Meccano Guild
99th Meeting Model Report 
98th Meeting Model Report 
 
97th Meeting Model Report 
(David Couch)
The Little Tram
An introductory Arduino project 
(G. Eiermann and M. Schild)
A Short History of MARKLIN Metall
 
96th Meeting Model Report 
83rd Meeting Model Report 
 
82nd Meeting Model Report 
Picks up three golf balls 
(Roger Marriott)
Midlands Meccano Guild
95th Meeting Model Report 
The Spanner Challenge 
 
 
94th Meeting Report 
(Andre Theberge)
Meccano Segway
Instructions 
(Andre Theberge)
A Meccano Segway
Arduino code 
(Andre Theberge)
A Meccano Segway
Assembly instructions 
(Michael J. Walker)
Meet the new MMG President
Geoff Wright 
The Spanner Challenge 
(Michael Walker)
Midlands Meccano Guild
93rd Model Report 
Report by Michael J. Walker. 
92nd Model Report 
(Stan Knight)
Minimal Meccano
Pocket Meccano Sets of the 1970s 
Little Lever, Bolton 
The Spanner Challenge 
91st Model Report 
(Bob Thompson)
Back to the beginning
Shop Display Model 
90th Meeting Report 
(Old Blue Gold)
Getting Old
A screwy story 
The Spanner Challenge 
Model report written by Michael J. Walker 
76th Meeting Report 
Exhibition in Nelson, New Zealand 
(Barry Gerdes)
Meccano Radio
 
 
How to flatten  
(Rod Socket)
Dear Mrs Spanner
Survival techniques for the Meccanoman's wife 
(Stan Knight)
The Top Ten Tools
Indispensable Tools for the Meccanoman 
A call for help 
The Spanner Challenge 
 
For small brass and nickel parts. Also for stripping paint and rotted zinc plating. 
(Stephen Heafield)
Waterslide Transfers
Refurbishing 0 & 00 Aero Models 
Construction details 
or Put Your Hammer Away 
Mobile Morris Crane from 1968 MM 
Bert Love's Blocksetter in colour 
The dangers of internet auctions 
(Rob Thompson pp Terry Bullingh)
BlockSetter Tower
Built by Terry Bullingham 
(Rob Thompson pp John Reid)
Captain Robert Falcon Scott
1912 Polar Sledging Party 
(Niels Gottlob)
Bucket Wheel Excavator
Transcribed from typed document with photos 
Selected Spanner messages 18th to 24th January 
Selected Spanner messages 11th to 17th January 
Selected Spanner messages 4th to 10th January 
 
(Norbert Klimmek)
Hulett Ore Unloader
A 1 to 32 Scale Model 
 
(Joe Attard of Malta)
A model ship
 
 
 
(Arup Dasgupta (ISM 652))
My E15R Motor
A repair story 
(Charles)
About Meccano
What is Meccano? 
Thoughts about modern Meccano 
Some hints and tips 
Not many in this condition I'll bet! 
 
 View all | Chat | Models | Hints and Tips | Opinion | Reviews | Mine