Group of Eighteen (18) Vintage 2A3 Vacuum Tubes Double Tested [SOLD]

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baileyler

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Group of Eighteen (18) Vintage 2A3 Vacuum Tubes Double Tested - [SOLD]

Trade considered (see below).

I will consider breaking up this group, but the individual tube price will be higher and not related to the group price.

Buy this lot and the 6A3 lot I have listed together, and I will take $100 off the total.

I am continuing to clean out some equipment and tubes, so I have this group of 2A3 vacuum tubes available.

This is a VERY long listing, so please read it in its entirety.

Tube #1 is an RCA branded VT-95 with black connected plates, double D getter elements, top mica supports, a date code of S5 and what appears to be an original box.

Tube #2 is an RCA branded VT-95 with black connected plates, double D getter elements, top mica supports and a date code of S2.

Tube #3 is also an RCA branded VT-95 with black connected plates, double D getter elements, top mica supports and a date code of S2.

Tube #4 is Tung Sol branded with black glass, dual flat plates, top mica supports, a date code of 26 and what appears to be an original box.

Tube #5 is a Ken Rad branded JAN-CKR-2A3 VT-95 with black glass, dual flat plates, top mica supports, a date code of Z4 and what appears to be an original box.

Tube #6 is a Ken Rad branded with black glass, dual flat plates, top mica supports and a date code of S2.

Tube #7 does not have a readable brand or date code (but is probably Ken Rad), with black glass, dual flat plates and top mica supports.

Tubes #8 is RCA Radiotron branded with black connected plates, a dimple getter element, a date code of X4 and spring-loaded filaments.

Tube #9 is RCA branded with black connected plates, a dimple getter element, a date code of R2 and spring-loaded filaments.

Tube #10 is RCA branded with black connected plates, double D getter elements and a date code of V1E.   When I originally got this tube, the base was very slightly loose, so I reinforced it with a small amount of epoxy around the base (hardly noticeable).

Tube #11 is also RCA branded with black connected plates, double D getter elements and a date code of V1E.   As with tube #10, when I originally got this tube, the base was very slightly loose, so I reinforced it with a small amount of epoxy around the base (hardly noticeable).

Tube #12 is RCA branded with black connected plates, double D getter elements and a date code of 704.

Tube #13 is an RCA branded USN-CRC-2A3 with black connected plates, double D getter elements, top mica supports and a date code of K1E.  This tube glows a little blue in the testers, but it tests nicely and shows no indication of any leakage or gas (see below).

Tube #14 is RCA branded with black connected plates, double D getter elements and a date code of 713.  The flashing on this tube seems to be a bit on the light side (but it tests good with no leakage or gas, see below).

Tube #15 is RCA branded with grey connected plates, double D getter elements and a date code of 417.

Tube #16 is Raytheon branded with grey connected plates, double D getter elements and a date code of E10.

Tube #17 is some type of rebranded tube (cannot read the brand, but is probably Sylvania made) with black connected plates, a dimple getter element and a date code of 11-64.  Please note that the top mica on this tube is missing a corner, and the base has some imperfections (but is tight), but these should not affect the functionality of the tube.

Tube #18 is Ken Rad branded with black connected plates, double D getter elements, side mica supports and a date code of M3.

I first tested these tubes on my Westmore 501 (gov’t version of Triplett 3444) connected to a regulated power supply.

On the Westmore, the Gm reject point for 2A3 is 2600 and average spec is 5200.

I also tested these tubes for plate current on the Westmore.  While there is no Westmore spec for plate current, the settings on the Westmore indicate that the test parameters are 250 V plate and -40V grid bias.  The Class A plate current spec for 2A3 at 250 V plate and -45 V grid bias is 60 mA (zero signal).

The results are as follows:

Tube #1   5600/64 mA

Tube #2   5000/54 mA

Tube #3   4800/52 mA

Tube #4   5300/76 mA

Tube #5   5200/64 mA

Tube #6   5200/54 mA

Tube #7   5300/66 mA

Tube #8   5300/60 mA

Tube #9   5100/64 mA

Tube #10   4600/60 mA

Tube #11   4200/58 mA

Tube #12   4800/72 mA

Tube #13   5000/62 mA

Tube #14   5000/58 mA

Tube #15   4700/54 mA

Tube #16   4400/65 mA

Tube #17   5500/68 mA

Tube #18   2600/28 mA

I also screened the tubes on a reasonably calibrated B&K 747 connected to a regulated power supply.  Since the B&K 747 does not have a 4-pin socket, the 2A3 were tested as 6B4G using an adapter.  There is no way to get 2.5V filament on the B&K 747, so filament voltage was set at 2V (which is a little low, but 3V gave too many off scale high readings).  The “GOOD” scale on the B&K 747 ranges from a numerical value of about 68 to 120, but I can find no specific indication of what an “average new” tube should test.  I have tested several different “new in box” tubes, and my experience is that the “average new” number will vary based on the tube.  Also, the scale is also not very detailed, so the numbers I give are approximate (+/- 2).

The results are as follows:

Tube #1   115

Tube #2   93

Tube #3   89

Tube #4   115

Tube #5   116

Tube #6   107

Tube #7   119

Tube #8    93

Tube #9   110

Tube #10   70

Tube #11   83

Tube #12   95

Tube #13   100

Tube #14   85

Tube #15   80

Tube #16   80

Tube #17   118

Tube #18   70

All tubes were clean for shorts, leakage and gas (grid emission) on both testers. 

As indicated above, tube #13 did glow a little blue in the testers, but did not show any indication of gas/grid emission.  Blue is usually considered OK (as opposed to purple which is bad), but I did want to mention it in the spirit of full disclosure.

All in all, the results are reasonably consistent between two very different testers (of course, with a small number of exceptions).

While almost all test nicely, all of the above should be considered "USED" for the purposes of this listing.

My strong preference is to sell as a group, but I might consider splitting them up for the right offer.

I can provide additional pictures or info on request.

GENERAL TERMS AND CONDITIONS

Please note that these tubes are being sold "AS IS, WHERE IS". THERE ARE NO GUARANTEES OR WARRANTIES OF ANY TYPE, AND THERE ARE NO RETURNS OR REFUNDS.

I ONLY describe what I know about the tubes, and what I have tested for.  While my tube testers tend to be reliable, YOUR TUBE TESTER MAY GIVE A DIFFERENT RESULT THAN MINE, so please take that into account.  In the event of a tube tester conflict, MY TUBE TESTER CONTROLS.

AS SUCH, PLEASE NOTE THAT I CANNOT GUARANTEE (OR EVEN REMOTELY PREDICT) HOW THESE TUBES WILL SOUND OR PERFORM IN YOUR EQUIPMENT.  ANY TEST RESULTS ARE ONLY PROVIDED AS AN INDICATION OF TUBE PERFORMANCE IN A VERY LIMITED (AND NON-IDEAL) ENVIRONMENT.  EXCEPT AS EXPRESSLY INDICATED IN THIS LISTING, I DISCLAIM ANY AND ALL REPRESENTATIONS, WARRANTIES AND LIABILITY WITH RESPECT TO THESE TUBES, OR RESPONSIBILITY FOR YOUR USE OF THEM.

Payment can be via money order/cashier's check/personal check but, except for US Postal Money Orders, all must clear my bank first. Cash is OK for a local transaction.

I also accept Paypal for convenience (but add 3% to the total for US, and 4% elsewhere). IF YOU PAY VIA PAYPAL, HOWEVER, A CONDITION OF YOUR PAYMENT IS THAT YOU EXPRESSLY WAIVE THE RIGHT TO FILE A PAYPAL CLAIM OR CHARGE BACK (but do retain the right to sue me in court should you so desire).

I am open to trade for things like Nordost speaker cables or ICs, a gaming desktop/tower computer (recent) or possibly compnents to build one, a solid-state hard drive (500GB or larger), certain vacuum tubes (like 5992, 7408, 6087, ECC801s, CV1985, L63, KT90 and others), a Roku (or similar) device, and various other odds and ends.

In any event, feel free to ask.

Shipping will be at the buyer’s expense. I prefer USPS Priority Mail, but that is up to the buyer. Insurance for full value is recommended, as I am not responsible for any damage in shipping or non-delivery (but will assist in processing any legitimate claim).  Each tube will individually wrapped in bubble wrap.  Shipping weight will likely be on the order of 10 lbs.

Please check my feedback on Ebay (ID=baileyler) and buy with confidence.










« Last Edit: 26 Dec 2017, 01:42 am by baileyler »

baileyler

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Bump.

If no interest, I'll end up packing these with a large group of tubes to be sold locally (Chadds Ford, PA) with some equipment and other miscellaneous stuff.

If anyone local (to me) is interested in that, please feel free to drop me a note.