Vacuum tube type: EZ81
Manufacturer: Tesla / RFT
Made in: Czechoslovakia / GDR

Plant: Tesla Roznov / VEB Funkwerk Erfurt

Condition: NOS/NIB (you can also choose NOS without box)
Box condition: mint/very good

Measured: no

I've been a collector of vacuum tubes for many years. Vintage electronics, radio engineering, and amplifier design have been my passions. Over the years, I've collected thousands of vintage parts, mostly from the tube era and originating from Eastern Europe. Since I started designing tube amplifiers professionally, I no longer feel like soldering in my free time because I do it at work. I've decided to sell my long-standing collection. I'm not a dealer, nor am I trying to make a fortune. I want to honestly sell items I've accumulated over the years, primarily of collector's value to enthusiasts like myself.

Most of the tubes I sell are NOS (new old stock), often also NIB (new in box). Some tubes are used, but fully tested and functional, and this fact is always stated in the auction. This applies primarily to more valuable types, such as the EL34. I don't sell used tubes of less valuable types in individual listings. Although I do have some, listing and processing the transaction would take more time than it's worth. I'll probably do group auctions with a mix of used tubes later.

I don't sell used tubes as NOS, although after browsing current eBay listings, I see that this is common practice. Having been involved in this industry for so many years, I can easily tell from a distance whether a tube has been used. When you buy from me, you'll be told honestly whether it's used, new from old stock (NOS), or new in box (NIB). Less valuable tubes sold in NOS or NIB condition are usually not measured – this takes a lot of time. By purchasing unmeasured tubes, you acknowledge that I offer no warranty – this is only for tubes I have measured.

When I sell NOS tubes, but without individual boxes (not NIB), that means that I got them either directly from bulk boxes or from spare parts for scientific instruments. I shall repeat: I do not sell used tubes as NOS, so don't be afraid tubes without boxes. Also, they are generally listed cheaper than NIB tubes.