Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: rzenc on August 11, 2010, 08:51:55 am

Title: 5Y3
Post by: rzenc on August 11, 2010, 08:51:55 am
Hi forum!
I need some 5Y3 and would like opinions from you.. I found some 5Y3GB but could not find any datasheet about this tube... Have you ever used such stuff??

Thanks in Advance
Best Regards

Rzenc
Title: Re: 5Y3
Post by: jjasilli on August 11, 2010, 09:40:13 am
http://www.mif.pg.gda.pl/homepages/frank/sheets/020/5/5Y3GB.pdf
http://www.audiophiletalk.com/cgi-bin/yabb2/YaBB.pl?num=1133228952
http://www.audiokarma.org/forums/archive/index.php/t-15147.html
http://www.tubeman.com/item128.htm
google has many hits
Title: Re: 5Y3
Post by: John on August 11, 2010, 09:41:50 am
The only thing I "know" (have been told  :smiley: ) is that the NOS tubes have a bigger voltage draw, you'll be able to drop the voltage coming off the PT that way. The newer ones are "better", in that they don't suck as much voltage. In my case, I needed the NOS to suck as much voltage as possible. Never fear, someone will be along that knows a LOT more than me.
Title: Re: 5Y3
Post by: FYL on August 11, 2010, 11:38:37 am
The GB version uses a largish T12/T14 bulb, the GT the usual small T8. Specs are the same except for heater current, 1.7A for the GB, 2A for the GT - AFAICT any other differences stem from a different rating system.

If your 5V supply is well behaved you can properly fit a GB, it'll be as good as a GT.

Title: Re: 5Y3
Post by: eleventeen on August 12, 2010, 12:35:24 am
I have some very nice 5Y3's for ya. Brown base, GE JAN NOS 6087/5Y3WGTB. From 1954. Pictures here:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=200502227605

PM me if you want. I myself don't think you're any better off with these than any kind of new 5Y3s. I hate how much it costs to ship these. But if you want brown base military ruggedized 5Y3's, I'll be cheaper than most any other source.

Title: Re: 5Y3
Post by: bigsbybender on August 12, 2010, 01:18:23 am
The only thing I "know" (have been told  :smiley: ) is that the NOS tubes have a bigger voltage draw, you'll be able to drop the voltage coming off the PT that way. The newer ones are "better", in that they don't suck as much voltage.

That would be the Sovtek.  It's actually not a 5Y3 but a close enough approximation that it can be used in the same socket so they label them as such. It has an indirectly heated cathode like 5AR4/GZ34 which allows for tighter tolerances within the tube, which in turn tends to have a smaller voltage drop. The directly heated cathode means the heater filament and cathode are the same part rather than two parts. Since they are the same part, the cathode is placed further away from the anode/plate than in an indirectly heated design. 

Actually in that case the SOVTEK should be labeled 5(insert letter here)4 since it is a four component tube instead of a 3 element tube like the original 5Y3.

I use the Sovtek on new builds since I can compensate for the additional voltage in any number of ways. On old amps I try to source originals.

j.
Title: Re: 5Y3
Post by: John on August 12, 2010, 05:36:33 am
Bigsby, thanks for the explanation. I bet at the time I was working on mine someone said the same thing differently, and I just didn't get it.  :smiley:
Title: Re: 5Y3
Post by: rzenc on August 12, 2010, 07:40:07 am
Thanks for the replies!!!

I had stocked JAN Philips 5Y3WGTA Black Plates but they are gone  :sad: I bought a box ~around 20 tubes, all new, but there are only 2 left.. and got 3 5E3 to be built.
I will give sovtek a try just in case...

Thanks

Best Regards

Rzenc
Title: Re: 5Y3
Post by: rzenc on August 13, 2010, 09:40:57 am
I have some very nice 5Y3's for ya. Brown base, GE JAN NOS 6087/5Y3WGTB. From 1954. Pictures here:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=200502227605

PM me if you want. I myself don't think you're any better off with these than any kind of new 5Y3s. I hate how much it costs to ship these. But if you want brown base military ruggedized 5Y3's, I'll be cheaper than most any other source.

PM sent mate!
looking forward to your answer

With Respect
Rzenc