Stumbled on to this while searching on similar topics. I enjoyed watching and subscribed. Very informative and helped fill some gaps of things I already knew, but just not as well.
Thank you for taking the time to make this (and others) and sharing what you know.
your videos helped explain in more detail then over a hundred vidoes and websites i have looked at have been able to thank you.
i had an idea if i made a coil with lets say 1000 turns and every 10 turns i make a loop. would i be able to get short, meduim and long wave by just moving to a different loop and have a variable capaciter to closer tune the stations
You're absolutely right: it would work as you say. In fact, very early on, that was probably the most common way of getting medium and long wave on one set without having the bother of unplugging one coil and plugging in another. In the earliest times, you just had a coil with many taps, selected by a rotary switch (or a slider) and relied on the capacitance of the aerial & other 'stray capacitance' to tune the circuit. Short wave reception is possible, but too difficult for me! Cheers.
so if i make a coil and use a slider think that be best more tuning ability couls i also use a 365pf varible cap in parallel with the coil for finer tuning is so how would i wire this i looked at loads of circuits and they all do it diferent ways so im very confused at present moment radio five live kills any channel selection on my fox hole radio
A 365 pF variable capacitor is ideal for tuning a Medium & Long wave crystal set. If 'Radio 5 Alive' is very powerful and 'swamps' other signals, you must first reduce the coupling of the aerial (antenna) into your foxhole crystal set. The simplest way to so this is by putting a small capacitor in series with the aerial. Say 100 pF, 200 pF. That will increase the selectivity, albeit at the expense of volume. I think this is illustrated in part 2 of my videos. Good luck!
@bixanorak funny you should say that i have a varible 125pf cap to the other idea i thoght about 2 sliders on the coil one for the diode and the other the antenna then place a 365pf varibale cap between the diode terminal and the ground terminal of the coil i think this way i should get a very large varation of coil winds to tunabailty what you think
Yes, that would work. Take the aerial in through the 125 pF variable to a tap on the coil, probably fairly low down it. Then take a tap higher up it to your 365 pF variable, & the other side of it to the bottom of the coil. Then take the signal from the 'hot' (upper) end of the 365 pF to your diode & from there to your headphones or amplifier. In this usage, the coil is called an 'auto-transformer' and the method was widely used in the early days.
Very interesting. I always wondered how a Crystal radio would work as I have seen several advertisements on old (Korean) newspapers - Thanks for posting this!
Hi, I'm Andreas! Really like your videos, are you going to receive a stereo signal later on? Have a nice evening, thanks for interesting and funny entertainment!
Thanks: glad you liked it! Yes, it does have a diode detector; in fact, it wouldn't work without one. The detector is the bit of crystal lying of the top plate of the capacitor, which has one strand of wire pressing on it. The contact point between the wire and a facet of the crystal acts as a diode. Hopefully I'll make more videos in this series, which will improve on this completely basic 'first attempt'.
Stumbled on to this while searching on similar topics. I enjoyed watching and subscribed. Very informative and helped fill some gaps of things I already knew, but just not as well.
Thank you for taking the time to make this (and others) and sharing what you know.
EvilPacketMonkey 2 weeks ago
ty think i gor that pictured in my mind
1981dasimpson 4 months ago
your videos helped explain in more detail then over a hundred vidoes and websites i have looked at have been able to thank you.
i had an idea if i made a coil with lets say 1000 turns and every 10 turns i make a loop. would i be able to get short, meduim and long wave by just moving to a different loop and have a variable capaciter to closer tune the stations
1981dasimpson 4 months ago
You're absolutely right: it would work as you say. In fact, very early on, that was probably the most common way of getting medium and long wave on one set without having the bother of unplugging one coil and plugging in another. In the earliest times, you just had a coil with many taps, selected by a rotary switch (or a slider) and relied on the capacitance of the aerial & other 'stray capacitance' to tune the circuit. Short wave reception is possible, but too difficult for me! Cheers.
bixanorak 4 months ago
so if i make a coil and use a slider think that be best more tuning ability couls i also use a 365pf varible cap in parallel with the coil for finer tuning is so how would i wire this i looked at loads of circuits and they all do it diferent ways so im very confused at present moment radio five live kills any channel selection on my fox hole radio
1981dasimpson 4 months ago
A 365 pF variable capacitor is ideal for tuning a Medium & Long wave crystal set. If 'Radio 5 Alive' is very powerful and 'swamps' other signals, you must first reduce the coupling of the aerial (antenna) into your foxhole crystal set. The simplest way to so this is by putting a small capacitor in series with the aerial. Say 100 pF, 200 pF. That will increase the selectivity, albeit at the expense of volume. I think this is illustrated in part 2 of my videos. Good luck!
bixanorak 4 months ago
@bixanorak funny you should say that i have a varible 125pf cap to the other idea i thoght about 2 sliders on the coil one for the diode and the other the antenna then place a 365pf varibale cap between the diode terminal and the ground terminal of the coil i think this way i should get a very large varation of coil winds to tunabailty what you think
1981dasimpson 4 months ago
Yes, that would work. Take the aerial in through the 125 pF variable to a tap on the coil, probably fairly low down it. Then take a tap higher up it to your 365 pF variable, & the other side of it to the bottom of the coil. Then take the signal from the 'hot' (upper) end of the 365 pF to your diode & from there to your headphones or amplifier. In this usage, the coil is called an 'auto-transformer' and the method was widely used in the early days.
bixanorak 4 months ago
Comment removed
1981dasimpson 4 months ago
I really enjoyed it Norman!
lindyhoppers 11 months ago
Very interesting. I always wondered how a Crystal radio would work as I have seen several advertisements on old (Korean) newspapers - Thanks for posting this!
transformingArt 11 months ago
Fantastic! Thanks Norman for reminding me of basic 'electronics' learned at school and long forgotten.
WalsallWatchMaster 11 months ago
Another wonderful lesson.
78rpmblog 11 months ago
Comment removed
78rpmblog 11 months ago
Hi, I'm Andreas! Really like your videos, are you going to receive a stereo signal later on? Have a nice evening, thanks for interesting and funny entertainment!
Falkis1984 11 months ago
Nice, no diode for detection?
legOldtimer 11 months ago
Thanks: glad you liked it! Yes, it does have a diode detector; in fact, it wouldn't work without one. The detector is the bit of crystal lying of the top plate of the capacitor, which has one strand of wire pressing on it. The contact point between the wire and a facet of the crystal acts as a diode. Hopefully I'll make more videos in this series, which will improve on this completely basic 'first attempt'.
bixanorak 11 months ago