John Curl's Blowtorch preamplifier part II

[scott wurcer]

A long time since we don't have seen posts from our beach bum. Do anybody have news from him ?

Recently active elsewhere.

 

[scott wurcer]

Lucky
I was surprised when i saw your TL cantilever model (*), Next I was even more surprised reading about the dispersion in your last post.
This clings 'guided waves testing' to me

Funny coincidence, I was at the MIT DIY flea market yesterday and one dealer had a very small stack of Audio magazine from the 50's. The one on top, June 1953, featured an electro-mechanical phono cartridge model.

EDIT - surprise https://archive.org/details/am-1953-06

Have to love it...
"Therefore, he feels the need to manufacture records for consumers who will ordinarily turn the bass control, if they have one, all the way up and the treble all the way down."

 

[Kindhornman]

Esperado,
I have been communicating with him offline mostly. He has been fairly active in the Bob Cordell book thread. Often he is off doing something else and isn't available to be online, but you can always PM him and he does get back to you when he can.

 

[jacco vermeulen]

(afaig, it usually means something else if a bum gets bombed at the beach)

 

[Esperado]

Esperado,
I have been communicating with him offline mostly. He has been fairly active in the Bob Cordell book thread. Often he is off doing something else and isn't available to be online, but you can always PM him and he does get back to you when he can.

Thanks, Steven.

 

[bcarso]

Funny coincidence, I was at the MIT DIY flea market yesterday and one dealer had a very small stack of Audio magazine from the 50's. The one on top, June 1953, featured an electro-mechanical phono cartridge model.

EDIT - surprise https://archive.org/details/am-1953-06

Have to love it...
"Therefore, he feels the need to manufacture records for consumers who will ordinarily turn the bass control, if they have one, all the way up and the treble all the way down."

That's a fun read. The lead piece about patents sounds as if it could have been written yesterday.

 

[gpapag]

Funny coincidence, I was at the MIT DIY flea market yesterday and one dealer had a very small stack of Audio magazine from the 50's. The one on top, June 1953, featured an electro-mechanical phono cartridge model.

EDIT - surprise https://archive.org/details/am-1953-06

Thanks Scott
Which leads us to US2695517

George

 

[scott wurcer]

That's a fun read. The lead piece about patents sounds as if it could have been written yesterday.

I am thinking of cutting that out and sending it around. Talk about how things never change.

 

[simon7000]

Folks,

I am having an off day. I want to build a frequency shifter in analog. I have a sine-cosine oscillator, a buffered signal, a 90 degree phase shifted signal, multipliers and summing amps. All I want is the lower shifted band. I have done this before but my memory has failed me today. Anyone want to refresh it?

Thanks

ES

 

[jcx]

looks good: http://zimmer.csufresno.edu/~pkinman/pdfs/Single Sideband.pdf

 

[Esperado]

I want to build a frequency shifter in analog

http://forums.parallax.com/discussion/download/83805&d=1312754326

 

[simon7000]

Thanks guys. Mind is working better today. Good thing have a small negotiation coming up.

 

[Esperado]

Is-it indiscreet to ask-you what for, this frequency shifter ?

 

[simon7000]

Is-it indiscreet to ask-you what for, this frequency shifter ?

Just showing cool sounds to a class.

 

[hitsware]

> Just showing cool sounds to a class.

Simpler then to just use squarewaves and xor gates ....

 

[simon7000]

> Just showing cool sounds to a class.

Simpler then to just use squarewaves and xor gates ....

Or I could be lying! Even easier to use a diode bridge.

 

[dvv]

Is-it indiscreet to ask-you what for, this frequency shifter ?

George Bermard Shaw stated: Questions are never indiscreete, answers sometimes are.

 

[jacco vermeulen]

(you mean that other Irish fag)

 

[Esperado]

George Bermard Shaw stated: Questions are never indiscreete, answers sometimes are.

Is-it indiscreet to ask-you if you are sure it was George Bermard Shaw and not Oscar Wilde ?

 

[dvv]

Yes, it was Wilde, you're right, and no, it is not indiscreete,