Rxes 5v4 instead of 5ar4

[cap217]

I have a couple nos 5v4 tubes just sitting around and I read that dr z says it's ok to use different rectifiers in his amps because he uses better iron. I read a lot about substituting these but want a final opinion before doing it. I would like to introduce some sag and that's the reason for this thread.

Also, I ordered a new sovtek 5v4 a while back but just looked at it for the first time and it looks nothing like a 5v4. It says on the top of the tube 5(y?)4c x-65. What is this?

[martin manning]

5V4 has lower DC output current capability than 5AR4... 175mA vs. 225 mA at 450V, so be mindful of that.

[David Root]

That y? is a u which is the Cyrillic alphabet for v. According to the Hoffman Amps website it is a "real 5V4".

It doesn't drop a lot more voltage than the 5AR4, about 25V vs 17V. If you are after some seriously tweedy sag in a 2.0 amp rectifier try a 5R4G/GA/GB. It is OK for 250mA DC, same as 5AR4. 5R4GB would be the cheapest. No new production in these but NOS is not expensive.

Check out the attached rectifier tube cheat sheet, lots of good stuff in it.

[Synchu]

Phonetically what is written on top of the tube is equivalent to - 5"tc"4s, where "tc" is pronounced like the beginning of the German word for ten (zehn). There's no such letter/sound in English (as far as non native speaker as me can be aware of ).

Couldn't find a datasheet in English, but here is Google translation from russian:
http://translate.google.bg/translate?hl ... es_sm%3D93

Original marking is 5ц4с.

Niki