What a beautiful innards and it makes me long for days gone bye. Thanks for showing.
More important Books!
Acoustical Engineering Harry Olsen
Radiotron Designers Handbook F Langford-Smith
Low-Noise Electronic Design Motchenbacher & Fitchen
Noise Reduction Techniques in Electronic Systems Henry Ott
A Textbook of Sound A. B. Wood (Rare!)
Machinery's Handbook Industrial Press (Expensive!)
Acoustical Engineering Harry Olsen
Radiotron Designers Handbook F Langford-Smith
Low-Noise Electronic Design Motchenbacher & Fitchen
Noise Reduction Techniques in Electronic Systems Henry Ott
A Textbook of Sound A. B. Wood (Rare!)
Machinery's Handbook Industrial Press (Expensive!)
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Good find, but the 1955 revised edition has more in it!
What is interesting is as some of the material was important for Sonar it didn't seem to show up in post war textbooks.
Ed have you seen "Mechanisms and Dynamics of Machinery" by Mabie and Ocvirk?
An amazing collection of information, more a textbook than handbook.
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Definitely a textbook. I like the Fortran bits. Some where I have an English translation of an extraordinary complete Russian machinery text from the late 1920's.
I did have a quite a few books lost in the 2004 flood. Unfortunately my mind is like an old steel trap, rusted shut.
BOY, n
1. noise with dirt on it.
--------------------------
In my defense,
I was left
unsupervised.
1. noise with dirt on it.
--------------------------
In my defense,
I was left
unsupervised.
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Boy Dirt Car (ironically appropriate)
https://www.youtube.com/watch?v=2Q3AmaIJqa8
I actually own this LP. What came first the dirt, the noise, or the cars?
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I have two of those Ed. The Radiotron Designers Handbook, Smith.
One is the 4th edition, very good reference the 1957 printing from Radio
Corporation of America, and the Newnes Classic edition.
The Crappy one is the 3rd edition isn't anything like the 4th edition.
It is a bunch of written stuff without diagrams, figures, etc.
Another good one is the Audio Cyclopedia, Tremaine, 2nd edition, first printing.
UPDATE: I put the filter on hold...I figured I should get the amp working first,
so I just got is working properly,. Nothing fancy, just a simple JFET,
2N5485, goal is design to a gain = 22. Bandpass from 15kHz - 30kHz.
The hard part was dialing in that gain. It was simple to get it to 10,
then some Drain and Source resistance sweeps, then I sat there in disgust.
Then I recalled I only have a VDD of 15 volts and swept it up
to about 20 V and made progress. Finally it was just sweeping
the S & D resistors and backed the voltage back down to a
+17 VDD and it worked like a champ.
So I've got 22.5kHz, .100 Vin and 2.200 Vout. Now it's fooling
around to make the filter work.
It doesn't do me any good to have a filter but not the amp
to provide a signal into it.
Now I've just got to doucment everything.
Cheers,
One is the 4th edition, very good reference the 1957 printing from Radio
Corporation of America, and the Newnes Classic edition.
The Crappy one is the 3rd edition isn't anything like the 4th edition.
It is a bunch of written stuff without diagrams, figures, etc.
Another good one is the Audio Cyclopedia, Tremaine, 2nd edition, first printing.
UPDATE: I put the filter on hold...I figured I should get the amp working first,
so I just got is working properly,. Nothing fancy, just a simple JFET,
2N5485, goal is design to a gain = 22. Bandpass from 15kHz - 30kHz.
The hard part was dialing in that gain. It was simple to get it to 10,
then some Drain and Source resistance sweeps, then I sat there in disgust.
Then I recalled I only have a VDD of 15 volts and swept it up
to about 20 V and made progress. Finally it was just sweeping
the S & D resistors and backed the voltage back down to a
+17 VDD and it worked like a champ.
So I've got 22.5kHz, .100 Vin and 2.200 Vout. Now it's fooling
around to make the filter work.
It doesn't do me any good to have a filter but not the amp
to provide a signal into it.
Now I've just got to doucment everything.
Cheers,
..... More culled from the DIYAudio's line of famous advice;
STRESS RELIEF TIPS
1. Stand up
2. Stretch
3. Take a walk
4. Go to airport
5. Get on plane
6. NEVER RETURN
STRESS RELIEF TIPS
1. Stand up
2. Stretch
3. Take a walk
4. Go to airport
5. Get on plane
6. NEVER RETURN
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I have the same one that I still use everyday and love it. Never had to open it and fix it, I hope I dont have to
If it wasn’t for the shielding the outer case provides, I’d have it always naked (porn fan here)
😀
>Edit. Like vacu I' d say
George
Yup - I also have a tek 475 amongst other scopes and kit I use for work and play! It's still a great scope!
Yes, the TEK 400 series of scopes was one of their best, and we have a tendency to hold on to what works, like the HP339 as well.
On another topic, I noticed on another thread that some here are still trying to get away with high q ceramics, as if there are no MEASURABLE problems with them. Some in DIY have even mentioned me, and my opinion, while using them. OK, do what you want, I will still advise against using most ceramic caps for coupling.
Now, I was not always this way. Back in the early 1970's, I thought that 2.2uF ceramic caps were potentially wonderful, and I replaced Mylar capacitors for them in a vacuum tube Fisher tuner that I used at the time. Over a while, I noticed a 'rougher' character coming from the tuner that I had used for many years. Guess what? It was coming from the ceramic caps. Once I replaced them, the problem went away.
Now, what about measurements? Yes, most ceramic caps measure really, really, badly when put to a stringent test.
Tektronix discovered the best way to test for ceramic non-linearity, and I happened to be at the factory, when they were testing out a modification to a TEK 577 curve tracer that showed the obvious problem. Many ceramics not only are nonlinear, but they can actually store charge like a battery, and have hysteresis. They are the very worst of virtually all caps, but they can be useful in cheap and dirty applications. Now, are there alternatives? Of course, you just have to care enough to use the right parts.
I would like to tell about an experience that I had with a potential job offer, back about 40 years ago.
I was offered a job to design a preamp from a California electrostatic loudspeaker company, who wanted to expand their products. This company already made some sort of active pre-equalizer for their speaker, and they gave me a schematic of it. I noticed a cheap ceramic cap used as a roll off filter at about 20KHz, so I explained to the VP of the company that this cap, in its present position could cause problems. I showed him measurements of a similar ceramic cap and I suggested that they switch at least, to Mylar. Well, after a few weeks, I was invited to San Francisco to meet the owner of the company. It was an interesting meeting, and Nelson Pass was there as well. In fact, that is the first time we had actually hung out together.
After awhile, at dinner, the big boss asked me if I was going to come online and work with them. I asked: 'Did you change the ceramic cap?' He said no, that he did not believe in such changes, so I then refused to work with him, pointing out that if even the obvious from me would be disputed by him, and it just was not worth it to suffer working with him.
That is how much I believe in using the right components in audio design.
On another topic, I noticed on another thread that some here are still trying to get away with high q ceramics, as if there are no MEASURABLE problems with them. Some in DIY have even mentioned me, and my opinion, while using them. OK, do what you want, I will still advise against using most ceramic caps for coupling.
Now, I was not always this way. Back in the early 1970's, I thought that 2.2uF ceramic caps were potentially wonderful, and I replaced Mylar capacitors for them in a vacuum tube Fisher tuner that I used at the time. Over a while, I noticed a 'rougher' character coming from the tuner that I had used for many years. Guess what? It was coming from the ceramic caps. Once I replaced them, the problem went away.
Now, what about measurements? Yes, most ceramic caps measure really, really, badly when put to a stringent test.
Tektronix discovered the best way to test for ceramic non-linearity, and I happened to be at the factory, when they were testing out a modification to a TEK 577 curve tracer that showed the obvious problem. Many ceramics not only are nonlinear, but they can actually store charge like a battery, and have hysteresis. They are the very worst of virtually all caps, but they can be useful in cheap and dirty applications. Now, are there alternatives? Of course, you just have to care enough to use the right parts.
I would like to tell about an experience that I had with a potential job offer, back about 40 years ago.
I was offered a job to design a preamp from a California electrostatic loudspeaker company, who wanted to expand their products. This company already made some sort of active pre-equalizer for their speaker, and they gave me a schematic of it. I noticed a cheap ceramic cap used as a roll off filter at about 20KHz, so I explained to the VP of the company that this cap, in its present position could cause problems. I showed him measurements of a similar ceramic cap and I suggested that they switch at least, to Mylar. Well, after a few weeks, I was invited to San Francisco to meet the owner of the company. It was an interesting meeting, and Nelson Pass was there as well. In fact, that is the first time we had actually hung out together.
After awhile, at dinner, the big boss asked me if I was going to come online and work with them. I asked: 'Did you change the ceramic cap?' He said no, that he did not believe in such changes, so I then refused to work with him, pointing out that if even the obvious from me would be disputed by him, and it just was not worth it to suffer working with him.
That is how much I believe in using the right components in audio design.
Sorry American humor...
I thought both of his definitions VERY funny as did my wife....
dennis h
Ceramic caps are not a single class of capacitor any more that treating a mylar cap as being interchangeable with a teflon cap. The high value small ceramic caps have very large voltage coefficients with the value decreasing substantially (90%) with voltage http://datasheets.avx.com/Y5V.pdf while others http://datasheets.avx.com/C0GNP0-Dielectric.pdf are largely interchangeable with teflon/polystyrene and will have much lower esr and inductance. However someone may like the distortion spectrum of a Y5V cap.
Given the voltage effects on Y5V (not to mention the microphonics and piezo effects) they would not be a good choice for most bypassing needs, even digital bypassing.
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