Richardson 5ar4

[Davec113]

I was poking around ebay after my Sylvania 5ar4 didn't survive the move. Everything else was ok, but I guess this tube was getting old. Or, it could be that the Sylvania was running in my preamp and I moved it to my Simple SE after the move. Anyhow, it instantly self-destructed in a shower of sparks.

I found these Richardson 5ar4s, does anyone recognize them?

http://cgi.ebay.com/RICHARDSON-5AR4-...#ht_500wt_1182

[OrganicBud]

It says it could be a relabeled Bendix, which was a good brand. It also appears to be in a JAN box, which also implies some integrity. I would never drop $38 for a rectifier though.

[Cobra2]

Why advertise "Richardson", is not National more well-known?

Arne K

[HollowState]

The tall miconal base and the third mica at the top if the structure does look very Bendix. It could be their version of the 6087 which was a GE 5 star rugged version of the 5Y3. Still, it looks like a nice tube. But leave it to shyster Richardson to re-label as they please.

[Davec113]

I also found this looking around the web...

I have a National 5AR4 that is actually a 6106. The 6106 is a very nice tube actually, but is an indirectly heated 5Y3, and originally a Bendix part. It is rated much less than a 5AR4 however

here:

http://www.harpamps.com/micKtubes/GZ34-Varieties.html

As far as price, I've had a couple Sovteks that didn't last and a JJ that shorted about 10 seconds after the preamp was turned off, which blew a couple fuses and a couple ps resistors before I realized where the problem was. I'd pay a few times what a JJ costs to get a reliable, long lasting 5ar4. I don't think I'll take the chance that the "Richardson" is actually a 5ar4, though it could work ok in the preamp, but maybe not the Simple SE....

[chrish]

I have had a failure of a JJ GZ34 that coincided with failure of the solid state rectifiers in my Simple SE. This was while I had a standby switch in the circuit. After removing the standby switch and the solid state rectifiers I have been using a Sovtek 5AR4 with no problems for over a year. I have also tried the soviet 5U3C (5U4G) with success. It does help to lower B+ a little if you need it, however it is directly heated and does not give the delayed power up of the 5AR4. They can still be found relatively cheap on ebay (but not as cheap as they used to be...).

Chris

[Bandersnatch]

hey-Hey!!!,
They're 6106's. IDH 5Y3. I got a set of 5 a while back, thinking I'd got a good deal on GZ34's. The seller took them back and then I found out about the Bendix tube....should have kept them; I got the sleeve for $27.
cheers,
Douglas

[Evenharmonics]

Will diode in series with 5AR4 plate as discussed here solve this problem?

[Davec113]

Originally posted by Evenharmonics
Will diode in series with 5AR4 plate as discussed here solve this problem?

I've heard this before, and planned on doing this and possibly inrush current limiting as well. But after a year and a half of running my Simple SE every day... it even sees duty for tv/video amplification as well... I haven't had any issues. The Sylvania is the first problem I've had with the amp, and I suspect that was due to moving. I also make sure I let the amp cool for a while before turning it on again.

However, I have been using a Mullard 5ar4 with the amp, I don't trust any of the current production tubes although I'm using one now that the Sylvania died.

[chrish]

Inrush current limiter is really easy to implement on this design, just solder one leg of the ICL to centre tap of the secondary and place the other lef of the ICL in to the screw terminal on the board. The diode trick would be more difficult, as the socket is soldered to the PCB.

I think it is worth trying the ICL before spending big on rare old rectifiers. Like I said, Sovtek working fine for me with this for over a year now.

Chris