locked Vacuum tubes
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I photographed some 40+ tubes at the last work session. They were not in boxes, but the manufacturers included RCA, GE, and Sylvania. The newspaper that each individual tube is wrapped in dates from the 1980s-1990s. This is a New Old Stock situation although we cannot guarantee that any of them work. That said anyone buying them knows that they may have to buy more than one to get a good one. If they need it back enough for vintage equipment, they will assume the risk.
Until we get done with the inventory and place a valuation on each tube, we will not really know what we have. Once you see the number of boxes of tubes and other components, you will release that this will be a long and tedious process.
Your comments give me hope that in the end it will all be worthwhile for SARC and the wider ham community plus maybe others.
Harold C. Fleischer, III
From: Richard Blank <rikblank@...>
Sent: Friday, December 20, 2019 8:45 PM
Cc: Bill Craft <billc851@...>; Harold C Fleischer III <haroldcf@...>; Richard Elder <rcelder@...>; Richard Roudebush <roudie3@...>; rosendo.guzman@...; Lloyd M. Swartz <lswartz@...>; Gary Harmon <gharmon@...>
Subject: Vacuum tubes
Since I am probably the only one on this list that actually works in the audiophile arena I'll chime in about tubes valuable to audio aficionados.
Assuming USA manufacturing, some of the tubes can be quite valuable today...with European manufacturer tubes possibly bringing more, from mfgs like Mullard, Siemans, GEC, Marconi, Telefunken, etc.
12AX7, especially European sourced tubes, even in American boxes, bring pretty serious money today
12AT7, less than the AX, but still desirable
12AU7, still not the AX level
Variants of the above, like the 6201, etc. can be quite valuable
7199, scarce, but used in Dynaco amps and some Scott amps, too, no direct replacement exists
6BQ5/ 7189. EL84
6V6, beloved by guitar amp users
6L6GC, these bring in good money if American made, the earlier versions,
6L6, 6L6G, GA, GB with lower plate dissipation figures not so much
5881, 5932, 7027 7581
KT-series tubes (European version of the beam power tubes, like the 6550, called "Kinkless Tetrodes", especially KT66, KT88, and KT77.
The 12 volt versions of these are still sought but do not bring in the same cash
6080 and 6AG7 are desirable, but maybe not real valuable
Mil-spec heavy duty tube rectifiers, the "potato masher" type.
Matching tubes takes more than something like a transconductance tube checker to actually match plate curves and current draws for proper biasing, my TV7-DU isn't one that will do that, but I've always wanted a tube curve tracer...
That's about all I can think of for now.
On Friday, December 20, 2019, 6:06:56 PM CST, Paul Guido <radioteacher@...> wrote:
I am out of town and cannot make it.
Tubes can be very valuable. Tested tubes even more so. Matched pairs on top of that.
Some tubes like large nixies and those sought by audiophiles should be tested and sold on a site like ebay. I would be happy to test some tubes on my Hickok 752. I also own a Nixie test unit.
Tubes like Tungsol 5881, USA made 6550 and 2A3’s are some of the ones I can name off the top of my head but there are many others.
That being said, I would be interested in buying up to four EL34s and four 6V6’s for an amplifier project I have at the market rate the group decides on.
We also want to be careful not to flood the market with tubes.
Any and all who wish to join us this coming up Monday please feel free to do so…