Forums :: NEW! Web Resources :: Features :: Photo Gallery :: Vintage Radio Shows :: Archives
Support This Site: Contributors :: Advertise


It is currently Nov Sat 26, 2022 3:35 pm


All times are UTC





Post New Topic Post Reply  [ 15 posts ] 
Author Message
 Post subject: Led/Tube homebrew?
PostPosted: Nov Mon 21, 2022 7:11 pm 
Member

Joined: May Tue 30, 2006 3:46 pm
Posts: 11576
Location: Santa Rosa, CA
I've built radios with type 30 or 1U4 tubes and never liked the idea that the filament is usually invisible when "illuminated".

This gentleman gave me an idea. https://www.theradioboard.org/forum/other-electronic-projects/12au7-mini-mini-watter

Seems easy to do with all-glass miniature tubes. I wonder if anyone has tried it with octals, like the 30 or 1G4 types? Seems like the bottom of the locating base could be drilled or cut away with a Dremel and an LED mounted in the socket in close proximity. I would use orange LEDs; the blue are kind of spooky. Although, one could use a blue and power it from the B+ current in a way that modulates the light with audio peaks. Just like a mercury vapor rectifier.

I don't want it to be merely a "display" tube; I want it to function in a radio.

Rich


Image


Top
 Profile  
 
 Post subject: Re: Led/Tube homebrew?
PostPosted: Nov Mon 21, 2022 10:17 pm 
Member

Joined: Jan Sat 25, 2020 4:23 am
Posts: 1236
Location: Colorado Springs, CO 80917
Location: Colorado Springs, CO 80917
Why would this be desirable? Unless we're making a night-light.
The LED sure doesn't prove the tube filament is working.
This seems like trying to gild a lily, or impress someone who knows nothing about tubes.


Top
 Profile  
 
 Post subject: Re: Led/Tube homebrew?
PostPosted: Nov Mon 21, 2022 11:48 pm 
Member
User avatar

Joined: Jan Thu 01, 1970 12:00 am
Posts: 5902
Location: Austin TX
I've seen some commercial units with that feature. For some reason they prefer blue LEDs. I like glows.


Top
 Profile  
 
 Post subject: Re: Led/Tube homebrew?
PostPosted: Nov Tue 22, 2022 1:46 am 
Member

Joined: May Tue 30, 2006 3:46 pm
Posts: 11576
Location: Santa Rosa, CA
WHY????

So it has the nostalgic glow of warm tube filament!

Rich


Top
 Profile  
 
 Post subject: Re: Led/Tube homebrew?
PostPosted: Nov Tue 22, 2022 2:27 am 
Member

Joined: Jan Sat 25, 2020 4:23 am
Posts: 1236
Location: Colorado Springs, CO 80917
Location: Colorado Springs, CO 80917
Quote:
So it has the nostalgic glow of warm tube filament!

But it's NOT.
It's the wrong color.
It's in the wrong place.
It doesn't get warm at all.
It's an unnatural abomination and should be banned!!
:roll:


Top
 Profile  
 
 Post subject: Re: Led/Tube homebrew?
PostPosted: Nov Tue 22, 2022 3:06 am 
Member

Joined: May Tue 30, 2006 3:46 pm
Posts: 11576
Location: Santa Rosa, CA
Amen, Brother!

Image

Anyone who misuses a vacuum tube should expect the Spanish Inquisition.

Rich


Top
 Profile  
 
 Post subject: Re: Led/Tube homebrew?
PostPosted: Nov Tue 22, 2022 4:43 am 
Member
User avatar

Joined: Jan Fri 17, 2014 6:26 am
Posts: 2513
Location: In the Village
Location: Phila., PA 19115
Rich, W3HWJ wrote:
I've built radios with type 30 or 1U4 tubes and never liked the idea that the filament is usually invisible when "illuminated".

This gentleman gave me an idea. https://www.theradioboard.org/forum/other-electronic-projects/12au7-mini-mini-watter

Seems easy to do with all-glass miniature tubes. I wonder if anyone has tried it with octals, like the 30 or 1G4 types? Seems like the bottom of the locating base could be drilled or cut away with a Dremel and an LED mounted in the socket in close proximity. I would use orange LEDs; the blue are kind of spooky. Although, one could use a blue and power it from the B+ current in a way that modulates the light with audio peaks. Just like a mercury vapor rectifier.

I don't want it to be merely a "display" tube; I want it to function in a radio.

Rich

I think that the newer Mcintosh amps use that feature! :D

Image

_________________
I like things that light up, tubes, bulbs, LEDs, whatever, and things that make noise.


Top
 Profile  
 
 Post subject: Re: Led/Tube homebrew?
PostPosted: Nov Tue 22, 2022 6:41 am 
Member
User avatar

Joined: Sep Mon 16, 2013 1:42 am
Posts: 5998
Location: Tucson, Arizona U.S.A.
Location: Tucson, Arizona U.S.A.
Why not just use a 6J5GT or 6C4 tube that naturally light up?

_________________
Jim Mueller

Who's that swimming in the punch bowl?
It's Walter Wart, the freaky frog!


Top
 Profile  
 
 Post subject: Re: Led/Tube homebrew?
PostPosted: Nov Tue 22, 2022 4:03 pm 
Member

Joined: May Tue 30, 2006 3:46 pm
Posts: 11576
Location: Santa Rosa, CA
As a youth, I grew up with the "Boys First Book of Radio" (Alfred Morgan). He used tubes that operated from filament batteries so that a power supply transformer and 120V AC connections weren't needed.

Sure you can use a 6V triode, but that complicates the power requirements. LEDs are perfect for battery radios.

Rich


Top
 Profile  
 
 Post subject: Re: Led/Tube homebrew?
PostPosted: Nov Tue 22, 2022 4:52 pm 
Member

Joined: Jul Thu 12, 2007 8:36 am
Posts: 799
Location: Boston,Ma
NOBODY expects the Spammish Repetition !

Rich : You are hereby sentenced to spend one hour in the comfy chair and to be severely poked with the soft cushions.


Top
 Profile  
 
 Post subject: Re: Led/Tube homebrew?
PostPosted: Nov Tue 22, 2022 6:31 pm 
Member
User avatar

Joined: Jan Thu 01, 1970 12:00 am
Posts: 18515
Location: S. Dartmouth MA USA
krystallo wrote:
NOBODY expects the Spammish Repetition !
Rich : You are hereby sentenced to spend one hour in the comfy chair and to be severely poked with the soft cushions.
100 lashes with a wet noodle :lol:

There has been recent posting(s) of the effect of photons on gas tubes. I have seen this effect myself from a an overhead fluorescent lamp (40w tubes)on a functioning 200a detector triode. A raspy hum. Now that is on a gas tube with a clear envelope, close the cover of the radio and the noise stops or shut the darn light off :roll:

That, makes me think if noises or the from "modulation" were to be impressed on the LED and inconsideration if the LED is a fast responsive type such as used in computer camera. What would be the effect on the electron stream and could this be used to any benefit such a signal injection or mixing?

Chas

_________________
List' & I will Enchant Thine Ear


Top
 Profile  
 
 Post subject: Re: Led/Tube homebrew?
PostPosted: Nov Tue 22, 2022 8:11 pm 
Member

Joined: May Tue 30, 2006 3:46 pm
Posts: 11576
Location: Santa Rosa, CA
The fluorescent tube problem is likely caused by "hash" due to the Hg ionizing and de-ionizing in the fluorescent tube. 83 mercury rectifiers have similar issues.

Interesting about using a fast LED, probably UV to modulate the electron stream.

I have used laser pointers to ignite old NE-2 lamps that won't fire in a normal circuit. Had an indicator light on an outdoor box that worked only in the daytime. Using a laser pointer, I could trigger it at night.

Rich


Top
 Profile  
 
 Post subject: Re: Led/Tube homebrew?
PostPosted: Nov Thu 24, 2022 10:57 am 
Member
User avatar

Joined: Dec Sun 25, 2016 4:53 am
Posts: 598
Location: Santa Barbara County Calif
I can picture a vacuum tube aficionado seeing that tube for the first time and freaking out, "OMG that tube is red plating like a son of a gun! " But wait, I see the plate isn't connected.
I have a few 5mm led's most likely intended for some sort of display effects. They cycle through a bunch of colors and flashing routines and then repeats them. That would really get 'em going if one was mounted at the base of glass envelope tube. Might even be hyped up as the latest exotic snake oil mod/upgrade.

_________________
1970's Avionics Tech, USN Attack Squadron 147, "ARGONAUTS" A-7E A/C


Top
 Profile  
 
 Post subject: Re: Led/Tube homebrew?
PostPosted: Nov Sat 26, 2022 1:28 am 
Member
User avatar

Joined: Dec Sat 24, 2011 8:17 pm
Posts: 10304
Location: Qualicum Beach, Canada
Instead of the switch, which doesn't look vintage, he should put a Morse code keyer on there.
"In a crowded room or a boring meeting, communicate silently with friends that know code!"

_________________
Watch the doughnut, not the hole.
Burl Ives, RIP, oldtimer.
[:l>)


Top
 Profile  
 
 Post subject: Re: Led/Tube homebrew?
PostPosted: Nov Sat 26, 2022 1:47 am 
Member
User avatar

Joined: Jan Thu 01, 1970 12:00 am
Posts: 2052
Location: Wayside, NJ Monmouth
Found this at a local Pharmacy. TRF AM and FM.


Attachments:
LED Radio.jpg
LED Radio.jpg [ 806.13 KiB | Viewed 37 times ]
Top
 Profile  
 
Post New Topic Post Reply  [ 15 posts ] 

All times are UTC


Who is online

Users browsing this forum: Vintage A and 1 guest



Search for:
Jump to:  




































Privacy Policy :: Powered by phpBB