Have you heard of a 5U4C Rectifier Tube?

[Ommy]

Does anyone have information on 5U4C rectifier tubes? I'm mainly interested in what tubes I can replace it with? Any help would be appreciated.

[Blue Strat]

Is the tube marked "Made in Chian" (sic)? I'm not kidding, lots of Chinese tubes are marked "Chian" instead of "China".

Any 5U4 tube, regardless of suffix, can be replaced with any other 5U4 tube regardless of suffix. REAL(not Chinese) 5U4 tubes are either 5U4G or 5U4GB...with the 5U4GB being most common and less expensive. Check out a NOS 5U4GB. They can be had for a little over $20 and typically last for decades (of years).

[Ommy]

While looking for replacement tubes I found that

"The numbers and letters "5u4c" seen on Russian tubes DO NOT mean 5U4C, 5U4 (G, B) or 5V4 or anything of the sort...
Those letters, U u and C c are Russian Cyrillic letter/characters, not English letters.

U = Tse (Ц, ц) is the 23rd letter of the Russian alphabet, and is thought to have come from the Hebrew letter Tsadi (צ) (Arabic: Tsad ص‎). It is a letter in the Cyrillic alphabet. It looks somewhat like U with square corners and a "pig tail" on the bottom right. It represents a voiceless alveolar affricate /ts/, like the ts in "cats."

C = Es (С, с) is the eighteenth letter in the Bulgarian, the nineteenth letter in the Russian, and the 21st letter in Serbian Cyrillic alphabet. It resembles the letter <C> in the Latin alphabet, being one of seven letters in the Cyrillic alphabet that share appearances with Latin alphabet letters but are pronounced in a different way (although the Latin alphabet's <C> can have a "soft" pronunciation before front vowels)."

- Quoted from Bruce of Mission Amps

[5992]

I think Bruce nailed it. The Russian "ts" sound looks sort of like a "U" and the Cyrillic "C" looks exactly like the Latin letter.

More info:

http://www.gstube.com/catalog/?key=5Ts4S+&submit=+GO+

[Blue Strat]

That's great, but my previous post in the thread is all you need do know to get the job done. Plus, it still hasn't been established for sure that his tube is Russian. Got a photo?

[5992]

Originally Posted by Blue Strat

That's great, but my previous post in the thread is all you need do know to get the job done. Plus, it still hasn't been established for sure that his tube is Russian. Got a photo?

I agree, we need a photo. If it is a Russian tube, it isn't the same as a 5U4. The other thought I had is that it could be a 5U4G tube.

A photo would really help.

[Blue Strat]

Originally Posted by 5992

I agree, we need a photo. If it is a Russian tube, it isn't the same as a 5U4. The other thought I had is that it could be a 5U4G tube.

A photo would really help.

No matter what it is, a US 5U4GB would be the correct replacement.

I know that there's a Russian 5U4G...to further complicate issues

[Ommy]

I couldn't get a good quality picture of my own that showed the letters, but I found a pic of a tube that looks exactly like my tube which leads me to believe it's a Russian tube. Also the U on mine has the same "pig tail" coming off it.

Also my tube says OTK and has an 0 in a diamond on the bottom piece.

It looks just like this:

[5992]

Originally Posted by Ommy

I couldn't get a good quality picture of my own that showed the letters, but I found a pic of a tube that looks exactly like my tube which leads me to believe it's a Russian tube. Also the U on mine has the same &quot;pig tail&quot; coming off it.

Also my tube says OTK and has an 0 in a diamond on the bottom piece.

I can't really make out the Cyrillic "ts" character, but from your description it sounds like the Russian tube that Bruce was talking about. In fact I remember him remarking that this tube doesn't have a Western counterpart. It is sort of like a 5V4 or 5Z4, but not exactly. I believe some tube sellers have even re-branded this tube as a 5Y3.

[5992]

Originally Posted by Blue Strat

No matter what it is, a US 5U4GB would be the correct replacement.

Why would that be? From the OP's subsequent description, it's not a real Western 5U4, it's more like a 5V4/5Z4/5Y3, but not exactly.

Originally Posted by Blue Strat

I know that there's a Russian 5U4G...to further complicate issues

That would be the 5Ц3C; the 5Ц4C crosses to 5Z4 & GZ30 according to my Russian/Western tube chart.

Here's a link to Russian tube data:

http://cityradio.narod.ru/spr/tubes/russian/all.html

Unfortunately, it's all in Cyrillic.

[Blue Strat]

Originally Posted by 5992

Why would that be? From the OP's subsequent description, it's not a real Western 5U4, it's more like a 5V4/5Z4/5Y3, but not exactly.



.

Well, since this is a guitar forum I'm assuming that the OP isn't talking about a tube he picked up at random and that it came as a stock part in an amp. So it has to be roughly equivalent to some standard guitar amp rectifier...wouldn't you think?

So before we waste more time speculating on something without enough information, OP, where did you find this?

[Ommy]

It came in a custom amp I bought. I think the power tube is Russian also; it reads 6n3c and the n looks funny.

[5992]

Originally Posted by Ommy

It came in a custom amp I bought. I think the power tube is Russian also; it reads 6n3c and the n looks funny.

If it is a 6П3C then it is a 6L6 equivalent. The П is a "P" sound in the Cyrillic alphabet, not an "N."

[Ommy]

So, do I have to stick with 5Ц4C tubes for the rectifier?

[Denyle_Guitars]

Originally Posted by 5992

If it is a 6П3C then it is a 6L6 equivalent. The П is a "P" sound in the Cyrillic alphabet, not an "N."

If that's the case, why not bump up the rectifier to a 5ar4?