View Full Version : Sometimes it's the little things.....RCA Pencil


soundmotor
10-29-2009, 04:58 PM
I was at the Todd Farm flea market last weekend and I stumbled up this, an RCA rotary pencil. The top half is a tube partially filled with glycerin or mineral oil and in that, a teeny RCA 5693 tube that can float up or down. At some point I am going to figure out how to open it and replenish the fluid. The barrel is engraved:

RCA (meatball logo)
"Special Red Tubes"
Radio Shack Corp.
Boston, Mass.

Pretty neat!

http://i139.photobucket.com/albums/q294/soundmotor/rca_pencil.jpg

Stephen J
10-29-2009, 05:01 PM
:thmbsp:

Sam Cogley
10-29-2009, 05:23 PM
What was a red RCA tube?

Cool pencil.

thefragger
10-29-2009, 05:24 PM
That's pretty awesome!!

soundmotor
10-29-2009, 05:45 PM
What was a red RCA tube?



Something you didn't realize you needed until this thread, red-based tubes!

;)

Super 6SJ7

https://www.cryoset.com/catalog/images/rca59631.jpg

Super 6SN7

http://www.tubemongerlib.com/gallery2/d/10287-1/RCA+5692+1950s+Black+Plate+Red+Base+1+-+USA.jpg

Super 6SL7

https://www.tubeworld.com/5691rca.jpg

Super 5Z4

http://www.the-planet.org/images/5690.jpg

Sam Cogley
10-29-2009, 06:39 PM
Something you didn't realize you needed until this thread, red-based tubes!

I assume the red signifies something? Most of them seem to have military numbers...

dsndblm
10-29-2009, 06:43 PM
I read an old RCA add that said the red base tubes had filaments rated at 10,000 hour life.

GordonW
10-29-2009, 07:19 PM
Too bad the only pair of red-base RCA tubes (5692) that I ever got, were the absolute noisiest 6SN7-type tubes I've ever encountered! Jet planes don't make that much rushing noise!

Guess they had already put in their 10000 hours before I came across them... :(

Regards,
Gordon.

sloober
10-29-2009, 07:44 PM
I have a Fisher pencil. Not as cool as yours. John
http://homepage.mac.com/johnhuber/AK/Fisher/pencil.jpg

soundmotor
10-29-2009, 09:14 PM
I assume the red signifies something? Most of them seem to have military numbers...

Yep, ~$100+ for NOS 5692's & $50+ for good/used. Contrast that with typical 6SN7 resale.

soundmotor
10-29-2009, 09:14 PM
I have a Fisher pencil.

That's very cool. Is it mechanical?

soundmotor
10-29-2009, 09:16 PM
Too bad the only pair of red-base RCA tubes (5692) that I ever got, were the absolute noisiest 6SN7-type tubes I've ever encountered! Jet planes don't make that much rushing noise!

Guess they had already put in their 10000 hours before I came across them... :(

Regards,
Gordon.

I've heard that complaint before about NOS ones too.

sloober
10-29-2009, 09:43 PM
That's very cool. Is it mechanical?

Yes Mechanical pencil from about 1948 I think. The best part is it was a gift from Chip Fisher.

JonL
10-30-2009, 12:50 AM
My old bunkmate Chip!

Mike Stehr
10-30-2009, 04:30 PM
I picked up a small box of parts at a estate sale today, and it had this little container in it.

JonL
10-30-2009, 04:45 PM
No pic?

spaceman
10-30-2009, 05:11 PM
That's pretty cool alright. :thmbsp: I didn't realize they made tubes that small before. ;) :D I'm learning to have more respect for RCA tubes lately, especially after seeing what their 6L6GCs go for.

Mike Stehr
10-30-2009, 05:47 PM
oops

http://img262.imageshack.us/img262/6043/002be.jpg

33&athird
10-30-2009, 06:22 PM
You guys are making me want things I can't find or afford :sigh:

Seriously neat stuff though...maybe I should root in the stock to see if we have any neat branded items. I would love to see a company produce stuff like this for their products now, I think a couple still do, but not many.

Hmm, i've seen a small tube like that before...I think it was called a transistor.:D