How a Magnatron works
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Paul Barker
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#1 How a Magnatron works
"Two things are infinite, the universe and human stupidity, and I am not yet completely sure about the universe." – Albert Einstein
#2 Magnatron
Nice one, Paul, very interesting you can never learn to much
Acorn
Acorn
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Paul Barker
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#3
Of course there are four items of interest inside a microwave.
A 2kv HT a high voltage solid state diode a 1ųF pio cap and a very effective EMI filter.
I haven't experimented with the transformer lately. Last time I tried it was much too noisy, but I have had the idea that two transformers, primaries connected in series, secondaries in parallel for "dual mono" which might not saturate (be noisy). It's cheaper in iron to allow a transformer to saturate when used in an oven which nobody cares if it is noisy. Then use one HT for one channel other for other channel.
In original form one end of the ht is earthed as they are half wave rectified, but this can be lifted from earth, and when you are halfing the HT you should be alright regarding voltage potential to the core at the end of the winding which is normally grounded, as after you lift it you will be careful what you do with it..
So you would get two supplies out at 1kv. Choke input 900v per channel lose a little here and there and you can supply HT to a direct coupled VT62 or 300b amplifier with an output winding per channel.
The low voltage winding is not so many turns that could couldn't unwind it and make a filament winding of your choice.
That is what you could do without grinding the welds apart. IF you did that you could rewind as an SE output transformer for fun. But as the lams are welded you won't get Onetics quality, though I expect the result would be perfectly listenable.
All I am saying is don't dump your microwave without salavaging these bits.
A 2kv HT a high voltage solid state diode a 1ųF pio cap and a very effective EMI filter.
I haven't experimented with the transformer lately. Last time I tried it was much too noisy, but I have had the idea that two transformers, primaries connected in series, secondaries in parallel for "dual mono" which might not saturate (be noisy). It's cheaper in iron to allow a transformer to saturate when used in an oven which nobody cares if it is noisy. Then use one HT for one channel other for other channel.
In original form one end of the ht is earthed as they are half wave rectified, but this can be lifted from earth, and when you are halfing the HT you should be alright regarding voltage potential to the core at the end of the winding which is normally grounded, as after you lift it you will be careful what you do with it..
So you would get two supplies out at 1kv. Choke input 900v per channel lose a little here and there and you can supply HT to a direct coupled VT62 or 300b amplifier with an output winding per channel.
The low voltage winding is not so many turns that could couldn't unwind it and make a filament winding of your choice.
That is what you could do without grinding the welds apart. IF you did that you could rewind as an SE output transformer for fun. But as the lams are welded you won't get Onetics quality, though I expect the result would be perfectly listenable.
All I am saying is don't dump your microwave without salavaging these bits.
"Two things are infinite, the universe and human stupidity, and I am not yet completely sure about the universe." – Albert Einstein
#4
Thanks for the tip off for this Paul, to resurrect this thread, I have just scavenged these parts before my old rusty/bare metal inside microwave hits the local recycling centre....
The EMI filter looks interesting, as far as I can make out, it basically looks like an X2 capacitor and choke across the live/neutral. Could this be dropped into my 801a amp power supply? I wonder what it would do?! Any experience of using it?!
Ta
Thomas
The EMI filter looks interesting, as far as I can make out, it basically looks like an X2 capacitor and choke across the live/neutral. Could this be dropped into my 801a amp power supply? I wonder what it would do?! Any experience of using it?!
Ta
Thomas
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Paul Barker
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#5
Yes they are fine. They are required so the microwave doesn't send EMI back down the mains and work just as effectively protecting your audio equipment from EMI coming from the line.
It's free ready made and one less job to do.
It's free ready made and one less job to do.
"Two things are infinite, the universe and human stupidity, and I am not yet completely sure about the universe." – Albert Einstein
