0B2

0C3 / VR105

Order Number: 114-027-26
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0C3 USA brands

105 Volt, 4...40mA precision stabilizer tube. No filaments, but a cold Cathode, only two electrodes. Works just like 4Watt Zener Diode. Lights bright purple. Put four of these in series and get a 420Volt/16Watt stabilizer diode for your 300B amplifier! These were used as precision references in equipment. Actually they are more precise than solid state Zener diodes.

0C3 / VR105
Tungsram

Order Number:125-005-51
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0D3 / VR150 Sylvania.

NOS. Only one. 5 Euro.

5U4G Svetlana
Winged =C=

Order Number 114-002-19
See price list.

Coke bottle glass. In original 1970's SVETLANA boxes with winged =C = logo.

Data sheet here

5R4GYB

5R4GYB Sylvania NOS 30 Euro. Only 1pcs.

5R4GYB Sylvania-

Cylinder glass, nice yellow print. Perfect ondition, 5R4 is comparable to 5U4G, but 5R4 is max 900V, 150mA. (5U4G is 450V, 225mA). 1970

5R4WGB NOS.

Order Number 114-121-48
See price list.  

5R4WGB, CETRON, Made in USA. The most rugged 5R4 have ever seen.Special socket for better high voltage behavior. Normally 5R4 has inside the base, side pins, for the anodes. These side connections are the weak point of 5R4, and they tend to develop a vacuum leak sometimes. You can not see these side connections, you need to break apart an old 5R4. If you do, the untrained eye can already see this is no ideal construction, and it may crack.

This 5R4WGB by Cetron does not have this. Instead of that, they used a hard glass base (like Pyrex) which has higher voltage capability, combined with the higher socket, which seals off the tube better. I believe this material is called mecanite, but I am not sure about the name of it.

What I can not prove, but it looks to me, this 5R4WGB can also replace any 5U4G or 5U4GB. It tests fully normal as 5U4G, and does what it has to do with ease.

BLACK plates.

W=military. G=Glass Bulb. B=Cylinder glass.

As always, and always... This excellent tube is nicely available for an extremely reasonable price. What does that mean? Well most of the time, with NOS tubes, it means that won't last for ever.

Picture of boxes

5V4 (GZ32)

4pcs. 45 Euro / One.

5V4 (GZ32) Edicron, London

Also check GZ32, it can replace GZ32

5Y3

Order Number 125-016-55
See Price list

Philips ECG.

5Y3 is Used in tube testers, guitar amplifiers and Hifi. It is hardly smaller than 5U4G. This is the second most used rectifier. NOS tube 5Y3GT you can still buy today. Though it's not a 7$ item any more like in 1995. Today it is not cheap any more, but also not expensive. So people are ok with the pricing and think it will stay like that for ever.

But....when NOS of these get rare, and they DEFINITELY will, prices will go the same way as 5U4G NOS prices.

5Z3 HALTRON

Order Number 114-094-77
See price list.  

Original old English NOS. Haltron, London UK.

5Z3 is electrically equivalent to 5U4G, but has a 4Pin socket like 300B. Why use expensive 5U4G, while you can get this nice coke bottled European tube? The Chinese sell also adapter socketson Ebay. Search for '5Z3 to 5U4G adapter'.

5Z3 SYLVANIA

Order Number 114-093-19
See price list.  

BLACK PLATES. Made by Sylvania for Philips ECG.

5U4G NOS is close to SOLD OUT where ever you go. People have been gazing at low 5U4G prices for 25 years, and thought it was normal. Suddenly now, 5U4G prices are 10x higher.

5Z3 is the same tube, just with another socket, so chances they will go the same way are 100%

All you need to do, is wait until it is too late, and you will see I was right.

5Z3 RCA, KEN-RAD, General Electric

See price list

6H6S

Order Nr: 114-180-76
See price list

6H6S/6X6C =D63=6H6GT

Uf=6.3V , If = 0.3A , Ua= 2x165V, Ia=16mA
Metal-bakelite base.
Equivalent to D63 and 6H6GT Western Tubes.

Lovely double rectifier, for instance to generate negative grid voltage. We sell those at very low cost. Vintage construction inside. Alone the base is worth it, to re-base other tubes with a metal base. For a give-away price! Check the price list.

6X4 USA

Order Nr:114-123-96
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6X4 TUNG-SOL USA.

Original box. Small rectifier, 7pin socket. For pre-amps, etc

6X5-GT USA

Order numbers: Click here
See price list

Looking for an ideal rectifier for small amplifiers? Well this 6X5 is the one! You have the nice octal based, non-miniature tubes, and 6X5 is from a period where quality was at it's best. 6X5 is not a fast starter, so it saves transformer and capacitors. Used by Audio Note Kondo and many others. For it's small size it can take quite a large capacitor. So 40uF at only 40mA will give very low ripple. Hint: If you want to use an 80uF Capacitor, you can just put two 6X5 in parallel.

80 Rectifier

Order Number: 114-181-89
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NEOTRON FRANCE

Beautiful French Made tubes, in original 50pcs factory carton. Date code 1961. Inside boxes are like new, and the tubes also. You do not find this every day!

80 Rectifier

Order Number: 114-127-71
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USA BRANDS. NOS.

The "80" has an UX4 socket, same as 300B. Most of them in original box. Small rectifier, with soft characteristic, for Audio applications, was used in radios and small audio amplifiers. Very hard to find as NOS. We have a limited stock of USA brands. More Pic1

UX380

Cunningham (by RCA) Once only. 80 Euro.

83V

2pcs. NOS. WB. Each 35 Euro

4687 Philips

1 pcs only. NOS, WB. 18 Euro

AZ1

45 Euro

VALVO Germany

Electrically equivalent to RGN1064.

AZ1

"INDUSTRIA" brand

18 EUro

AZ1

Order Number R112
30 Euro

AZ1 RFT

Mint quality tube + original package. Was opened only for picture and tests. Pict1 - Pict2.
Click both pictures, for Test results with Funke Tester.

AZ1

Order Number R127
30 EUro

AZ1

10 EUro

VALVO

Globe, mesh tubes. Very strong testing tube, but on the glass top, where the logo is (was...), are deep scratches in the glass.

AZ1

70 Euro

VALVO

Globe, mesh tubes. Used, excellent quality.

AZ4

sorry...need
to make pictures

Glass bulb and
plates look
like the same as AZ12
below here.

NOTE AZ4 is the same as AZ12, but another socket.

AZ4 Tesla or Polam.

Audiophile secret tip!

WHY use the expensive RGN2504? Do you really need 250mA max? If you can do with a tube that has 200mA, max here is what you need ....

AZ4 is a 200mA type rectifier, electrically close to RGN2504, also a 4Volt tube, and also with the wide plates of RGN2504, and also eight filaments. So AZ4 is almost the same tube as RGN2504. The difference is 50mA and another socket type for AZ4. Personally I like the socket of AZ4 more, because it works so nice when you plug and unplug the tube. We have bakelite sockets NOS for AZ4 on stock.

EZ90

GR100DM

GR150DA by DGL France

NOS GR150DA vs used GR150DA

THESE ARE FROM ORIGINAL FUNKE spare parts kits. For all Funke testers.

In it's original box. Extremely rare.

datasheet here

There is NO replacement for GR150DA. Even Funke writes, you can not use standard GR150, but it must be specially selected GR150DA.

Unlike what some fools say, you should NOT put some 150V device in the tester, because load characteristic is different (read text further down here), and Funke test cards are based on that particular load characteristic of the FUNKE SELECTED type, which is called GR150DA. This si, because most triodes react very strong to just a few Volts changes of the anode voltage. If you do not believe this, put a 2A3 tube at 148V at Grid 0V, and at 151V at Grid 0V. That will make quite some difference.

The GR150-DA is a very special product. It cannot replaced by anything else. It has a dynamic impedance, which the Funke test cards are adapted to. It is specially made for Funke. In the Funke Blue book, that is with the testers, it describes clearly in German: You can buy this tube only from Funke, do no use someting else..

We have a small lot here, in original double packs, by DGL, with pink printing on it: Made for Funke. THESE ARE WHAT YOU NEED.

The special voltage to current chart of the GR150-DA, plays a role in the "good begins at....." indication, on the test card. Even the FUNKE MANUAL says you may only use the "DA" Version and no other. The "DA" is a specially selected version for the Funke testers. These are original words by the Funke company, in their blue book.

Though the tube itself is 150V, 5...60mA, it is possible to build a stabilized a power supply from 0...100mA, and 150V or more. The trick is, not everything will go through the tube. Some part goes into the load as well Check the circuit diagram of the Funke W19 tester, for an excellent application example to get a whole range of stabilized voltages, up to 250V, 0...100mA with only one 150V tube. This schematic demonstrates the forgotten art of using tube stabilizers, there is no better example.

The light effect of the tube is magnificent. In daylight it looks very bright as well. This is a mesh wire tube. So you can look through.

For Funke testers, GR150DA can replace GR150A. (but GR150A cannot replace GR150DA)

Please follow the link on the left, if you are interested in technical details. I have measured a normally working, seemingly "good" tube, and compared it to a NOS. The difference is very large. So it seems clearly older GR150DA tube become imprecise. I found they can have an impedance of 700 Ohms. vs. almost zero ohms for a new tubes. I don't want to explain here, how this can cause wrong results, but you can believe me it does. Mainly it will do so with low impedance triodes.

Note: NOS tubes have a faint shade of pink added to the neon color. You can even see that on the pictures here. Older tubes burn in deep orange color same as any old neon lamp. So even when you think a GR150DA tube is "good", the accuracy becomes very questionable when a worn out GR150DA has 700 Ohm plate impedance, virtually adding up to the plate impedance of the tube your are testing. Better take a NOS tube, and keep the old as a spare. Or sell the old on Ebay, I have seen people pay 150 Euro there for a used tube.

GR150-DK

with Bayonet Base. 18 Euro one

datasheet is on www.4tubes.com

GR150DK is the same tube as the Funke tube GR150DA , except it is lower current, and it has a bayonet base.

The base is the same a double filament 12Volt car lamp. So for instance like a t 5+21Watt lamp. This socket for this tube should be really easy to get. I would recommend to use the Funke W19 schematic, but change it for the lower current of this tube. So effectively with the big GR150DA as used in the FunkeW19 schematic, you can get 150, 200 or 250Volt at 0...100mA. With this little tube GR150-DK, 0....25mA should be possible.

Use of this stabilizer:

If the load is guaranteed, not to change within +/-12.5mA, you can as well stabilize 100mA with it. Possibilities are larger than you think, and occasional overload will do no damage.

GZ32 Brimar UK

Price 95 Euro one

Amazingly nice glow picture, because of plate holes. Mint condition item.

Also check 5V4, it can replace GZ32

GZ32 MULLARD

145 Euro one

Boxes are cleaner than clean. Mint condition item.

Also check 5V4, it can replace GZ32

GZ32 RUSSIA

PV200/600 Tungsram

Order Number 125-005
See price list

Gorgeous looking tubes, with nice yellow printing on it. They look much nicer than on the pictures. Bases are clean and very tight. Great tube, because it can do 600VDC at 200mA.

Construct a bridge rectifier with four of those, (Ongaku Method) and you get a 1200Volt, 200mA for GM70 or 211. This tube has excellent value for the money. Low forward voltage!

RG62D

RG105

Order Nr: 114-129-34
See price list

RG105 Telefunken

A fantastic NOS TELEFUNKEN rectifier, for a very reasonable price! Of course people "do not like" this tube, but they don't know what they are saying! They say so because of 2.5V heating, and they decided, they don't like that. So you can take advantage of the price :)

This tube can deliver 250mA from a 2,5V 4,5A heater.

But not consider this for any application where you need 250mA or more. First, when you want to pull 250mA from any 250mA tube, you will see (well, after reading the data sheet) this is possible yes, but at reduced output voltage. So in order to get high voltage at high current, you need to put two tubes in parallell anyway. It works like that with all rectifiers.

Now, with RG105, take two of those, put the heaters in series, and the plates in parallel. This would result in four pins again, and the new heater is now 5V, 4.5 Ampere. Probably a heater specification you like more. The result of this construction is, a maximum 500mA rectifier, and it will do high voltage too, at say 300mA. Moreover, this heater is now 2.5-0-2.5V and you can even the "0" as a center as tap. You do not have to, but it's nicer, and increases efficiency of the circuit slightly too. (It's why some heater transformers have a center tap).

Here is a schematic showing how to put 2.5V rectifiers in series, it is for another tube type, but for RG105 it would work identical. With this schematic there is also a center tap used.

G354 (=RGN354)

Order Number R151, one only. 15 Euro

RGN1054

RGN1064

Order Nr: 125-146-67. 1pcs only. 160 Euro

TELEFUNKEN RGN1064

Pristine Quality mesh tube. Original box, with some factory papers inside. Same production code number on the box and on the tube. Extremely hard to get with such optical appearance. One of a thousand is like this.

RGN1064

Order Nr: 125-147-98. Some pieces 110 EUro

TELEFUNKEN RGN1064

Identical tubes like above. Very small use. Measure and look like 100% new. Packed in a standard Telefunken box from the 1950's, but not the blue band on it.

RGN2004: See UU5 / UU7S

RGN2504 Mullard

Mullard factory codes

These are stamped Siemens or Philips AZ50, but they are Mullard RGN2504 re-branded as Philips AZ50.

They have the Mullard typical design inside, and on some tube is written "Made in England" . Some have the Mullard typical small printing on the back. It cannot be seen well from the pictures here, but the plates are from solid copper. This is also typical Mullard. From the plate edges it can be seen clearly with some of the tubes, but not with all.

Second the are not AZ50 because this tube has 3 Amps heater current. However, for those tubes here, I measure exactly 2,5 Amps with each of them. So these are definitely RGN2504, and not AZ50.

Bases are very clean and very tight. Printing is reasonable with all tubes, but not better as the one here pictured. Print color is bright white with all of them. Here is your change to buy NOS RGN2504 by Mullard!

UU5 (=RGN2004)

MAZDA UU5 = RGN2004
Order number 125-126-78

MWT CV1039 / MAZDA UU5
Order number 125-127-48

See Price list

UU7S

Order number 114-193-87
See price list

UU7S

5U4G

READ THIS WHEN YOU ARE A TECHNICAL FREAK!

UU7S IS A GENIUS TUBE!

UU7 is a British tube, with OCTAL base and 4Volts heater. However it is a relatively small performance tube, similar to RGN1064 or AZ1.

UU7S is something different. It's performance is comparable to 5U4G.

UU7 / UU7S connections are made DIFFERENT from 5U4G family. This was done on purpose, to make sure 5V and 4V tubes are not inserted wrong by mistake.So plug UU7 in an socket, intended for 5U4G, will give intentionally no tube function.

However with an intelligent socket connection, BOTH tubes can be used, without looking at it, and 4V or 5V is switched automatically by the socket itself. For this, just connect it like in the table below.

What is special about the UU7S, vs UU7? Historically, any tube with „S“ designation, was a special version of some kind, mostly by re base suitable NOS tubes. It was done the same here. The S-Version has higher DC current output, and higher maximum AC voltage input, making this tube come closer to 5U4G, which was the basic intention.

UU7S is upwards compatible with UU7. So UU7S can replace any UU7, but UU7 is too weak to replace UU7S.

Here is a nice idea: You can wire the socket such that BOTH tubes will work, just plug it in, and the socket will switch automatically from 4V to 5V.

Note, 5U4G can do maximum 250mA, they write in the RCA data sheet, but the clever engineer will quickly read there, it is only valid if choke loaded. If capacitor loaded, it is only 225mA, and even so, this 225mA is not allowed at high voltage. Moreover the first capacitor of UU7S can be almost twice as large as with 5U4G- So all in all, UU7S and 5U4G are not so much different in performance.

How to use 5U4G and UU7S simultaneously:

UY1N TESLA.

Several pcs. 12 Euro /one