[dfkt]

I can get a (reasonable priced) GZ34 tube from a friend who doesn't know much about tubes (very much like me). It would be a replacement rectifier for my Woo Audio 6 amp.

The tube reads following codes:

BNH4
F32
B1H4

Could anyone tell me the manufacturer/year of this GZ34? Or direct me to a link with the relevant tube codes? I did a Google search but didn't come up with anything useful. Thanks for any help!

 

[edisonwu]

F32 is a mullard code for GZ34. The tube was made in the UK by Mullard during the fourth week of August, 1971.

 

[Rob N]

Made in Blackburn.Date could also be 1961

 

[dfkt]

Thanks, guys. I assume this is not a metal base GZ34?

The year seems fine, I assume... 1961 seems like the times when people knew how to make tubes. 1971 doesn't sound too bad, either. Could this tube be any good?

May I ask what lists you have to translate the codes?

 

[Agent Kang]

Sorry for being slightly off-topic but I'm very interested in knowing which types are good GZ34 tubes.

 

[dfkt]

Metal base GZ34, Amperex or Philips... they go for $200-400 on eBay.

 

[Agent Kang]

Thanks for your reply. I'm also looking for rectifiers for my woo 6. It's too bad 200-400 is a lil out of my price range.

 

[Rob N]

Mullard GZ34 is certainly good quality.

It won't be a metal base as they were only made in the 1950's.

 

[edisonwu]

both 1950's Mullard & Amperex Metal base were made by Philips with Philips codes. the early big brown or black base Mullard is the second best on the list. Some people may prefer the mullard.

 

[dfkt]

Now my friend made some pictures of the tube. It certainly looks used, judging by the pins.

Could anyone say if it's still in proper working condition, by these pics?

http://www.anythingbutipod.com/image...pt/tube/01.jpg
http://www.anythingbutipod.com/image...pt/tube/02.jpg
http://www.anythingbutipod.com/image...pt/tube/03.jpg
http://www.anythingbutipod.com/image...pt/tube/04.jpg

(Pics are 1200x900 pixels - 56k beware.)

 

[Captain ?degard]

1800x900 pixels

Any idea how much i should take for this thing (im the one who has it)

 

[takezo]

judging by the pins only it certainly looks used...a good look at the top of the silver flashing may help...if you see dark spots or burn marks in the silver flash it probably means well worn...if you don't see much silver flashing-> well worn...if the top silver flashing looks opaque and transparent-> well worn...

maybe you should take it to a small t.v. repair shop and ask them to test it for you, for a small fee...it's the only sure-fire way of knowing how much more life it has left...

 

[Captain ?degard]

Quote:

Originally Posted by takezo /img/forum/go_quote.gif judging by the pins only it certainly looks used...a good look at the top of the silver flashing may help...if you see dark spots or burn marks in the silver flash it probably means well worn...if you don't see much silver flashing-> well worn...if the top silver flashing looks opaque and transparent-> well worn... maybe you should take it to a small t.v. repair shop and ask them to test it for you, for a small fee...it's the only sure-fire way of knowing how much more life it has left...

Hmm its packed away for shipping now, but its in the original box so i doubt very much its been used. silver was as far as i remember perfect. the pins have to colors, split in two, that mgight be what gives it that look.
anyways, he's not paying anything up front so its all good

edit: opened a bit and looked. silver on top of the tube is totally fine, no spots whatsoever from what i can see

 

[dfkt]

Quote:

Originally Posted by takezo /img/forum/go_quote.gif judging by the pins only it certainly looks used...a good look at the top of the silver flashing may help...if you see dark spots or burn marks in the silver flash it probably means well worn...if you don't see much silver flashing-> well worn...if the top silver flashing looks opaque and transparent-> well worn...

I got the tube now, and it looks good to me. No spots, burn marks, or anything I could discern - but OTOH, this is the first tube I got, besides the stock tubes my Woo6 came with.

The pins look like they're half covered in solder - don't know if that was a common practice in the days of yore. Some of the parts inside the tube don't look well aligned, some pretty awkward angles where some of the connections meet, and the top and bottom plates aren't really well aligned either. Don't know if that shows anything.

Here are some macro photos I took, hope they show some of the relevant parts.

Click on the thumbnails for bigger photos (1600x1200):

 

[jamato8]

That was one of the last types made. The serrated edge is what they used in the last production types. The serrated edge with less notches was earlier.