General > General Technical Chat
What ever happened to TV technicians?
<< < (10/17) > >>
Zoli:

--- Quote from: NiHaoMike on May 08, 2022, 08:10:19 pm ---...
I assume you're referring to build quality since modern transistors and opamps perform vastly better than old ones. They're still improving albeit well into diminishing returns.
...
--- End quote ---
I challenge you to build the Alexander amplifier(https://www.analog.com/media/en/technical-documentation/application-notes/58052492001115525484056221917334an211.pdf) with current transistors, and show the original performance(output power, distorsions, bandwith).
Case rested.
vk6zgo:

--- Quote from: NiHaoMike on May 08, 2022, 08:10:19 pm ---
--- Quote from: cdev on May 08, 2022, 04:56:17 pm ---Old audio equipment is often better than new audio equipment so is often worth fixing.

--- End quote ---
I assume you're referring to build quality since modern transistors and opamps perform vastly better than old ones. They're still improving albeit well into diminishing returns.

I also read claims that old music (especially from the days of tube amps) was mastered with technical limitations of that era consumer equipment in mind and sound "wrong" on modern equipment, similar to retro games looking really poor on a modern gaming monitor.

--- End quote ---

Audio reproduction long surpassed the capacity of human hearing, so a lot of modern specs seem to be for their own sake, rather than any audible improvement.
That said, many FM/AM tuners from the later 1970s to today, are very poor, particularly on AM, where the reproduced bandwidth is barely better than communications quality, wasting the relatively wide audio response of AM stations in those countries which still transmit baseband audio out to 9 or 10 kHz on AM.
NiHaoMike:

--- Quote from: Zoli on May 09, 2022, 12:44:55 am ---I challenge you to build the Alexander amplifier(https://www.analog.com/media/en/technical-documentation/application-notes/58052492001115525484056221917334an211.pdf) with current transistors, and show the original performance(output power, distorsions, bandwith).
Case rested.

--- End quote ---
I'm pretty sure there exist specialty amplifiers for scientific equipment with even more impressive specs than that, especially with respect to bandwidth.

There also has been a trend of audio ADCs and DACs going up to 384kHz sample rate and beyond. While that's not going to make audible differences for the original application, it did come with the side benefit of making a reasonably low cost source of high speed, high resolution ADCs and DACs for stuff like narrowband SDR and ultrasound experimentation.
Zoli:

--- Quote from: NiHaoMike on May 09, 2022, 02:26:47 am ---
--- Quote from: Zoli on May 09, 2022, 12:44:55 am ---I challenge you to build the Alexander amplifier(https://www.analog.com/media/en/technical-documentation/application-notes/58052492001115525484056221917334an211.pdf) with current transistors, and show the original performance(output power, distorsions, bandwith).
Case rested.

--- End quote ---
I'm pretty sure there exist specialty amplifiers for scientific equipment with even more impressive specs than that, especially with respect to bandwidth.

There also has been a trend of audio ADCs and DACs going up to 384kHz sample rate and beyond. While that's not going to make audible differences for the original application, it did come with the side benefit of making a reasonably low cost source of high speed, high resolution ADCs and DACs for stuff like narrowband SDR and ultrasound experimentation.

--- End quote ---
If you are so sure, why don't you link it?
Thank you.
VK3DRB:

--- Quote from: Circlotron on May 08, 2022, 12:13:12 pm ---
--- Quote from: vk6zgo on May 07, 2022, 01:49:03 pm ---The thing is, they did have a solid background of theory, although not to an EE level.

--- End quote ---
I tip my hat to any old school TV repairman that understands the finer points of a vacuum tube horizontal output stage.

--- End quote ---

Of the top of my head.... 6AL3, 6CM5!

I had a huge collection of TV valves and gave them to Arthur Courtney (the original founder of Resurrection Radio) when he was one of the managers at IBM. Sort of spewing I did that, but Arthur was a top bloke.

Navigation
Message Index
Next page
Previous page
There was an error while thanking
Thanking...

Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod