Semiconductor history - Revision history

Cornish semiconductor at 16:33, 12 July 2026

2026-07-12T16:33:16Z

← Older revision		Revision as of 16:33, 12 July 2026
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	The advantage of the crocodile clips and flying cat's whiskers approach I've been using is that you are much less restricted with the size and constituency of the crystal, it can have large amounts of matrix material with it for example. However, this 1920s design is more stable, as it does stay quite well 'set' once you find a good spot. Having said that, knocking it, or the table still causes jumps and changes in states so the radio must have still be tricky to keep working.		The advantage of the crocodile clips and flying cat's whiskers approach I've been using is that you are much less restricted with the size and constituency of the crystal, it can have large amounts of matrix material with it for example. However, this 1920s design is more stable, as it does stay quite well 'set' once you find a good spot. Having said that, knocking it, or the table still causes jumps and changes in states so the radio must have still be tricky to keep working.

			It has taken it's place in the [[Variscan Synthesis]] live rig, as part of the [[diode ladder filter]] this is because of it's extra reliability. If used in addition to using crystals in a noise generator it's handy to having something a bit more stable filtering the results otherwise it's hard to get them both working at the same time.

	==Full radio set==		==Full radio set==

Cornish semiconductor: /* Full radio set */

2026-07-01T09:54:07Z

Full radio set

← Older revision		Revision as of 09:54, 1 July 2026
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	==Full radio set==		==Full radio set==

	I managed to get a full radio, with all the parts needed to run. It's extremely cute - very small compared to most of the examples I've seen, but still in the same style, in a mahogany box with the ubiquitous BBC stamp. It was made in 1923 by a company called [https://www.radiomuseum.org/r/master_master_junior.html Master Radio Manufacturing Co. Ltd. Carver St., Old Trafford, Manchester (1925)]		I managed to get a full radio, with all the parts needed to run. It's extremely cute - very small compared to most of the examples I've seen, but still in the same style, in a mahogany box with the ubiquitous BBC stamp. Presumably designed as a kid's "my first radio", it was made in 1923 by a company called [https://www.radiomuseum.org/r/master_master_junior.html Master Radio Manufacturing Co. Ltd. Carver St., Old Trafford, Manchester (1925)]

	[[File:Junior.jpg\|center]]		[[File:Junior.jpg\|center]]

Cornish semiconductor at 09:52, 1 July 2026

2026-07-01T09:52:57Z

@@ Line 24: / Line 24: @@
 Neutron were a company that was immensely popular for a few years - apparently following [https://www.radiomuseum.org/dsp_hersteller_detail.cfm?company_id=6631 16 months of R&D] they developed a crystal that "doubled the range" of a radio receiver. Inside the tin we find several galena crystals, all bright and fresh - I've often wondered how long it takes for fresh galena to tarnish, it seems these have lasted well since the 1920s. Apparently the best galena was argentiferous, or silver bearing. Some of the Cornish mines also reported silver sales from galena processing.
-==Radio sets and crystal diodes==
+==Radio parts and crystal diodes==
 [[File:Radio.jpg|500px|right]]
@@ Line 60: / Line 60: @@
 The advantage of the crocodile clips and flying cat's whiskers approach I've been using is that you are much less restricted with the size and constituency of the crystal, it can have large amounts of matrix material with it for example. However, this 1920s design is more stable, as it does stay quite well 'set' once you find a good spot. Having said that, knocking it, or the table still causes jumps and changes in states so the radio must have still be tricky to keep working.

Cornish semiconductor at 06:37, 20 June 2026

2026-06-20T06:37:47Z

← Older revision		Revision as of 06:37, 20 June 2026
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	[[File:Dismantled.jpg\|500px\|right]]		[[File:Dismantled.jpg\|500px\|right]]

	This design is really well thought out as the whole thing can be dismantled easily, so the cup containing the crystal can be replaced or the cat's whisker changed. It works so much better than my attempts, as it holds much more securely to the location you pick, and the glass will protect it from dust.		This design is really well thought out as the whole thing can be dismantled easily, so the cup containing the crystal can be replaced or the cat's whisker changed. It works so much better than my attempts, as it holds much more securely to the location you pick, and the glass will protect it from dust. See also [[historical cat's whisker designs]] for photos of more of these.

	I've managed to carefully remove the crystal holder from the radio panel (and kept all the screws and bolts for safe keeping so I can rebuild it) and put it on a wood base, as the enormous variable capacitor (which give a range between 0.7 and 1.3 pF) was making it cumbersome.		I've managed to carefully remove the crystal holder from the radio panel (and kept all the screws and bolts for safe keeping so I can rebuild it) and put it on a wood base, as the enormous variable capacitor (which give a range between 0.7 and 1.3 pF) was making it cumbersome.

Cornish semiconductor at 17:20, 9 June 2026

2026-06-09T17:20:52Z

← Older revision		Revision as of 17:20, 9 June 2026
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	[[File:Radio-xtal-curves.png\|center]]		[[File:Radio-xtal-curves.png\|center]]

	The ~~advantages though~~ with this design is ~~its stability~~, ~~something I've not really been prioritising - but~~ it does stay quite well 'set' once you find a spot. Having said that, knocking it, or the table still causes jumps and changes in states so the radio must have still be tricky to keep working.		The advantage of the crocodile clips and flying cat's whiskers approach I've been using is that you are much less restricted with the size and constituency of the crystal, it can have large amounts of matrix material with it for example. However, this 1920s design is more stable, as it does stay quite well 'set' once you find a good spot. Having said that, knocking it, or the table still causes jumps and changes in states so the radio must have still be tricky to keep working.

Cornish semiconductor at 22:04, 8 June 2026

2026-06-08T22:04:32Z

← Older revision		Revision as of 22:04, 8 June 2026
Line 48:		Line 48:

	I've managed to carefully remove the crystal holder from the radio panel (and kept all the screws and bolts for safe keeping so I can rebuild it) and put it on a wood base, as the enormous variable capacitor (which give a range between 0.7 and 1.3 pF) was making it cumbersome.		I've managed to carefully remove the crystal holder from the radio panel (and kept all the screws and bolts for safe keeping so I can rebuild it) and put it on a wood base, as the enormous variable capacitor (which give a range between 0.7 and 1.3 pF) was making it cumbersome.

			==Testing the crystal diode==

	[[File:Radio-xtal-test.jpg]]		[[File:Radio-xtal-test.jpg]]

Cornish semiconductor: /* Radio sets */

2026-06-08T22:02:55Z

Radio sets

← Older revision		Revision as of 22:02, 8 June 2026
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	Neutron were a company that was immensely popular for a few years - apparently following [https://www.radiomuseum.org/dsp_hersteller_detail.cfm?company_id=6631 16 months of R&D] they developed a crystal that "doubled the range" of a radio receiver. Inside the tin we find several galena crystals, all bright and fresh - I've often wondered how long it takes for fresh galena to tarnish, it seems these have lasted well since the 1920s. Apparently the best galena was argentiferous, or silver bearing. Some of the Cornish mines also reported silver sales from galena processing.		Neutron were a company that was immensely popular for a few years - apparently following [https://www.radiomuseum.org/dsp_hersteller_detail.cfm?company_id=6631 16 months of R&D] they developed a crystal that "doubled the range" of a radio receiver. Inside the tin we find several galena crystals, all bright and fresh - I've often wondered how long it takes for fresh galena to tarnish, it seems these have lasted well since the 1920s. Apparently the best galena was argentiferous, or silver bearing. Some of the Cornish mines also reported silver sales from galena processing.

	==Radio sets==		==Radio sets and crystal diodes==

	[[File:Radio.jpg\|500px\|right]]		[[File:Radio.jpg\|500px\|right]]

Cornish semiconductor at 22:01, 8 June 2026

2026-06-08T22:01:09Z

← Older revision		Revision as of 22:01, 8 June 2026
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	This design is really well thought out as the whole thing can be dismantled easily, so the cup containing the crystal can be replaced or the cat's whisker changed. It works so much better than my attempts, as it holds much more securely to the location you pick, and the glass will protect it from dust.		This design is really well thought out as the whole thing can be dismantled easily, so the cup containing the crystal can be replaced or the cat's whisker changed. It works so much better than my attempts, as it holds much more securely to the location you pick, and the glass will protect it from dust.

			I've managed to carefully remove the crystal holder from the radio panel (and kept all the screws and bolts for safe keeping so I can rebuild it) and put it on a wood base, as the enormous variable capacitor (which give a range between 0.7 and 1.3 pF) was making it cumbersome.

			[[File:Radio-xtal-test.jpg]]

			I then tested to see what curve traces I could get from it - exciting to pass some voltages over this crystal for perhaps the first time in a century. It's not that different from what I've been used to seeing, which in itself is interesting - I had wondered if I was replicating this properly for a while. The curves represent different spots on the crystal, and you see some different behaviours - and a bit of inverse curves which I've seen from galena before.

			The top right is typical of it 'properly' performing as a rectifying diode, the voltage jump in the positive region on the right happens at a very low voltage, and rivals a germanium diode. It is quite leaky though, as it starts conducting (although, with some resistance) at higher negative voltages.

			[[File:Radio-xtal-curves.png\|center]]

			The advantages though with this design is its stability, something I've not really been prioritising - but it does stay quite well 'set' once you find a spot. Having said that, knocking it, or the table still causes jumps and changes in states so the radio must have still be tricky to keep working.

Cornish semiconductor at 14:15, 7 June 2026

2026-06-07T14:15:45Z

← Older revision		Revision as of 14:15, 7 June 2026
Line 45:		Line 45:
	[[File:Dismantled.jpg\|500px\|right]]		[[File:Dismantled.jpg\|500px\|right]]

	This design is really well thought out as the whole thing can be dismantled easily, so the cup containing the crystal can be replaced or the cat's whisker changed.		This design is really well thought out as the whole thing can be dismantled easily, so the cup containing the crystal can be replaced or the cat's whisker changed. It works so much better than my attempts, as it holds much more securely to the location you pick, and the glass will protect it from dust.

Cornish semiconductor at 14:10, 7 June 2026

2026-06-07T14:10:20Z

← Older revision		Revision as of 14:10, 7 June 2026
Line 35:		Line 35:

	The raised plug at the top is where you plug in a secondary inductor coil which could be bought separately. The panel is probably made from bakelite and the knob and plug block is perhaps ebonite - both early forms of plastic that would have seemed like dazzling and futuristic materials at the time.		The raised plug at the top is where you plug in a secondary inductor coil which could be bought separately. The panel is probably made from bakelite and the knob and plug block is perhaps ebonite - both early forms of plastic that would have seemed like dazzling and futuristic materials at the time.

			[[File:Radio-close.jpg]]

			[[File:Radio-micro.jpg\|500px\|right]]


			I was so happy to get such a good example of this kind of crystal setup - a precursor to all diodes to come! The cat's whiskers match the ones in the 'mighty atom' tin, and the pressure on the crystal is quite a lot more than I thought it would be. The handle end has a ball bearing so you can move it around to find a working spot. I think the cat's whiskers are made from silver, which apparently works best with galena. The crystal itself seems too dark for galena, but on close inspection it shows cubic formations and the hardness is a match so I presume this is tarnish. The top surface is scratched into rounded masses, but there was an area on the side that had been protected showing these original crystals.

			[[File:Dismantled.jpg\|500px\|right]]

			This design is really well thought out as the whole thing can be dismantled easily, so the cup containing the crystal can be replaced or the cat's whisker changed.