John Curl's Blowtorch preamplifier part II

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I'd stick a 100-200 pF cap before the ferrite directly to the chassis.

I did a lot of work in an EMC chamber about 20 years ago. Without the devices I would not have gotten the products through Qualcom and eventually accreditation. Testing was IIRC 50MHz up to 3GHz. Very tough to pass, but we made it.
 
So, lets stop applying 'Bybee Science' and focus on solving engineering issues with engineering solutions.

Found a copy of Walt Wood's dowsing kit while doing the laundry (no idea where it came from). It's pretty easy to get the hang of the standard J-hook dowsing rods, they want to act like they have a mind of their own. I kid you not, in less than a minute I could walk past the cold water line and the thing just kept pointing right at it. I'm impressed. The map dowsing with a pendulum is impressive too as well as using dowsing to neutralize GMO foods.

https://www.youtube.com/watch?v=AxQzuV6Zhy4
 
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well if you want to stop EMI you need to give it a lower impedance path out the way. So a ferrite on its own may not help. But of course you knew that!

Fingers of course are the best way of either coupling in or removing RF from circuits 🙂

when I were a lad in the lab we had a slightly out of spec batch of 7/16 RF connectors come in. You could change intermod performance by 30dB just by adjusting tightness a few Nm.

I keep 1 nF ceramic capacitors in the kit with the beads. Just very hard to get the local 50 KW 1020 kHz AM station out of nearby systems. Then are the folks with light dimmers so much noise so close to audio.. Very fond of input transformers.


Found a copy of Walt Wood's dowsing kit while doing the laundry (no idea where it came from). It's pretty easy to get the hang of the standard J-hook dowsing rods, they want to act like they have a mind of their own. I kid you not, in less than a minute I could walk past the cold water line and the thing just kept pointing right at it. I'm impressed. The map dowsing with a pendulum is impressive too as well as using dowsing to neutralize GMO foods.

https://www.youtube.com/watch?v=AxQzuV6Zhy4

Scott,

I don't know if you are kidding or ill! 🙂
 
I don't think they were shut down, it is just that the were no longer selling to the DIY market. Loudspeaker manufacturers want to keep the best drivers to themselves! But recently I have seen new Audax drivers being marketed again to our crowd. Don't know about your tweeter though.

Yes, I found the Madison ad as well. Looking it over, I notice that it seems all three dirvers used in by speaker boxes are still on offer, although their markings seem t have changed as well, so my tweeter is now gold plated (WTF?), but the price is still about the same, $ 110 per piece, in 2002 mine cost €97 (catalog list price, I actually paid less, the company owner is a friend of old). I'm not surprised, in their time they were considered the best from Audax.

I also saw quite a few models which were used by JBL in their commercial modles while they were being made in Denmark. The pro drivers were never generally sold, although JBL would sell them on specific request, but don't ask about the price, not good for your health.
 
You should read up on the dowsing culture, if I train hard enough I should be able to pick out the best resistors. No I actually found this is a pile of stuff we are culling from the mess, in getting ready to possibly move. Seems OP and rather dear for what it is. I'm sure my wife paid a $1 or two for it.

Amazon.com: Powers That Be (9780883639313): Walter Woods: Books

I will believe that if you train hard enough that you can pick out the best resistors, but not by dowsing, physics and engineering would get you there faster. OP??
 
Hovland went under inspite of their tube and transformer dowsing. And the dowsing dude claimed to have a brother that could dowse for gold. With all that, no Hovland and no gold. It may find water, but I ask; Then wouldn't all the dowsers be here in California making a killing and I could take showers without guilt?
 
Hovland went under inspite of their tube and transformer dowsing. And the dowsing dude claimed to have a brother that could dowse for gold. With all that, no Hovland and no gold. It may find water, but I ask; Then wouldn't all the dowsers be here in California making a killing and I could take showers without guilt?

My guys picked up a case of bottled water at the local Home Depot. It was labeled as produced in California! Then you do know where much of the Budweiser beer is produced? L.A.

I am pretty sure I have mentioned my great uncle was issued a horse and two mules to help with making the maps to do the dam at Boulder and irrigate your neck of the woods.
 
My guys picked up a case of bottled water at the local Home Depot. It was labeled as produced in California! Then you do know where much of the Budweiser beer is produced? L.A.

I am pretty sure I have mentioned my great uncle was issued a horse and two mules to help with making the maps to do the dam at Boulder and irrigate your neck of the woods.
And huge amounts of Cali' water is used to grow Almonds that are shipped to China!

Pakleds quote "we are not smart"

But "thank you" to your great uncle.
 
I'd stick a 100-200 pF cap before the ferrite directly to the chassis.

I did a lot of work in an EMC chamber about 20 years ago. Without the devices I would not have gotten the products through Qualcom and eventually accreditation. Testing was IIRC 50MHz up to 3GHz. Very tough to pass, but we made it.

Sorry, that should have read qualification and not Qualcom.

F;;(;🙂g Apple spell corrector again.
 
Found a copy of Walt Wood's dowsing kit while doing the laundry (no idea where it came from). It's pretty easy to get the hang of the standard J-hook dowsing rods, they want to act like they have a mind of their own. I kid you not, in less than a minute I could walk past the cold water line and the thing just kept pointing right at it. I'm impressed. The map dowsing with a pendulum is impressive too as well as using dowsing to neutralize GMO foods.

https://www.youtube.com/watch?v=AxQzuV6Zhy4

Well, he claims they found the big chief!

Do you think you could find the Perrier?

😉
 
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