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[212Mavguy]

Just recently scored this on Ebay. Search 290230400217 labeled Texas instruments...so here's an impromptu vintage old stock tube ID that takes some tube weenie knowledge to solve...

Who made it?

When was it produced?

What is current ebay market value for the properly ID'ed tube?



:?: :wink:

 

[Timbre Wolf]

Tube troll?? :roll: Hey, you're doing great with your sleuthing! I can only add that "280" is the Raytheon EIA manufacturer's code (RCA is 274, Sylvania 312, Tung-Sol 322, GE is 188, etc.). So it is likely a Raytheon.

Cheers to you both!

- T

p.s. Mav: I'm enjoying a "new" (to me) Siegmund micro tube boost - quite a bit!!

 

[212Mavguy]

Greetings from Mommy's basement and ****, that Chicken pot pie tastes so good! :lol:

Shredd, your tube pussy knowledge is both humorous and consistently accurate. Kudos! There is always something good to digest in your posts. The only place we might agree to disagree is market value, with a more informed description it will likely bring more like 40-60 bucks. The JAN type red print, blackplate, triple mica, windmill getter tube in your pic is considered by many to be a holy grail type 5751. A really nice pair went for around 150 bucks more than once recently on ebay. That is on the high side, par is around 50 bucks plus or minus 10 each for vintage old stock. I have a few, and a couple of identical tubes with a rectangular getter wire instead of the unique to Raytheon windmill getter structure and yellow Raytheon label instead of red. As wonderful as the windmill units sounded, the wire getter pair I have are even better, even more detailed, possibly due only to having run less hours than the windmill units before I got them.

Moderately microphonic 9 pin preamp tubes can often be made more usable by shrinking two layers of 1" heatshrink tubing over the bottle sides appropriately cut to allow the tube to still socket in a skirted 9 pin socket/shield setup... in a head instead of a combo amp. The longer the amp stays on, the hotter and more rubbery the heatshrink becomes, increasing damping.

Wolf, Siegmund makes amazing stuff. Glad you are enjoying your micro tube boost. I love my Doubledrive. Did you check to see if he has a secondhand buyer's warranty available for your pedal? I have one on my Midnight Blues Breaker head. Tough for others to chase your tones when you have anything Siegmund makes in your tone chain.

Peace.

 

[212Mavguy]

Well, it came in today and just spent the last two hours plugged in...Wow! Classic Raytheon blackplate 12__7 family tone and dead quiet for microphonics. 8) It was definiely used, but not used up by nearly any means.

The sound could only get better and stronger after cleaning the pins, but even socketing it straight out of the post box it was very smooth, balanced top to bottom, musical, abundant rich, sweet harmonic content, and strong in gain. For the price I paid I practically stole it considering performance alone.

 

[Timbre Wolf]

Niiiiiiiiiiiiiiice!! 8)