A cheap stereo from the 90s was like that. Switch built into the arm.
I prefer the Garrard turntable my grandfather built into a big wooden box with big amplifiers. Auto stop, cushioned lowering of the stylus etc. Very smooth everything, the turntable had a lot of inertia in it, must have been a big heavy flywheel underneath for smooth rotation.
Sounds like a good way to stop your neighbour listening to the radio.
Did valve radios use Cockcroft-Walton multipliers?
I doubt it was illegal at that short a distance. You can (or could recently) buy a transmitter to convert something (mp3?) into FM to go to your car stereo. It wouldn't get far outside the car.
Mains was always AC wasn't it?
Would that change the frequency?!
That's one I have heard, but I have also heard that it is false, as brass does not contract so much faster than iron, as to cause a problem.
Yes. That's one I've heard too.
In fact it would have to be the opposite, the iron contracts more do it drops thru what holds the cannon balls when cold enough.
Don't buy that with the prefabs and we can see that your number is a lie using google street view.
I didn't read carefully. I thought he said trimming the capacitor that's in one of the tuned circuits.
No, trimming the length of the antenna would likely just decrease transmission range.
If there were no friction between train wheels and track acceleration and braking wouldn't happen.
The reason railway tracks are so level is so that the engines can have the minimum power to pull the train. Very steep inclines would require extra locomotives to be put on to get up the hills.
If course it wasn't (in the UK). Mains was AC or DC, and 120V (or so) to
250V (or so).
Yes. Mains power was produced locally to each town or city. It was only the building of the grid that standardised mains voltage and frequency across the country.
No, transformers for AC mains, dropper resistors for DC, HT/LT batteries for portables and vibrator power packs for car radios. (Or valves with
12V HT and a power transistor for hybrids.)The low power FM transmitters came later. Recently I bought Thomson wireless headphones that use UHF and reach out into the car park: much better than Bluetooth and with no latency.
They used to be very stuffy about home transmitters in the past: If you learnt Morse code you could become a radio ham. I think you could have a radio controlled toy running at 27 MHz, though might have needed a licence. People imported 27 MHz walkie-talkies but they were illegal to use. I think they eventually made CB radios legal.
Steam locos were not rated in horsepower, but 'tractive effort' . How many tons of pull they could generate before the wheels slipped.
That's why they had a lot of driving wheels - at least four, generally 6 and up to 8.
At a given slope even the loco alone cant get up it which is where rack and pinion railways come in.
Mains was always AC post WWII and probably post the advent of consumer tube radios and IIRC was always 240VAC post WWII.
"The Electricity (Supply) Act 1919 merged the 600-odd local generating companies into area boards, who in turn were centralised into the Central Electricity Board by the Electricity Supply Act 1925. That is when the voltage was standardised at 240V, and the National Grid created.
(But DC persisted, in some areas as late as the mid 60s. Refrigerators, Vacuum Cleaners, Sewing Machines, Electric Drills, Radios and TVs were available with universal input. They would all work on AC or DC 240V (one or two DC areas were only 180V, like Dundee or Exeter))"
There were at least two classes of licence - you needed to learn morse for the higher licence that permitted more options and made for long range communications.
27MHz AM radio control had been around for a long time and I don't think a licence was required. 35MHz FM came in later, again no licence required.Imported CBs were 27MHz AM and caused problems with ambulance service communications IIRC. When CBs were legalised, it was on 27MHz FM, with the AM sets remaining illegal and the FM sets being limited to 4 Watts. Only 40 channels were legal, although some imported sets could access 80.
And then the EU stole ten of our good, English volts!
Have we got them back yet?
That rather contradicts your first para.
You were usually recommended to use each needle only once. Gramophones often had a little caddy to put the used needle into.
Shellac is very hard. Before I could get proper needles for an electric record deck I inherited I use panel pins without any trouble.
[Snip]
In the early 1960s, Cambridge was supplied with 200v.
In the 1960s it required a license. The advent of CB "good buddy, there's a bear up your rear' types more or less destroyed the band.
RC moved up to 35Mhz and 40Mhz. 27 is now cars and toys only. No licenses were required
They did.
Not really.
When CBs were legalised, it was on 27MHz FM, with
Not sure that is correct. 27 was always AM. I dont think there were more than about 10 channels either
DC and non 240V was highly localised and never part of the National Grid.
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