Horrible, horrible, horrible things.
Only capable of passing 1200mA, and 100W anode dissipation at 67 ohms ra. Horrible for OTLs.
You MUST send them to me for safe disposal, or even better send me some 7242s if you have any
Seriously, though, if you have enough, you could probably make quite a nice OTL. Datasheet here.
Only capable of passing 1200mA, and 100W anode dissipation at 67 ohms ra. Horrible for OTLs.
You MUST send them to me for safe disposal, or even better send me some 7242s if you have any
Seriously, though, if you have enough, you could probably make quite a nice OTL. Datasheet here.
Because of the valve's characteristics, you'll need a low turns ratio transformer capable of handling quite a large DC current, but yes, they will work for SE amplifiers. With the large Pa rating, I would imagine quite a lot of power would be available - probably >20W, but you'll have to keep an eye on the bulb temperature (not literally, of course )
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Excellent tube!
Geiasoy Gianni!
What a wonderfull tube this is! I never imagined you could find such tubes locally! Anyway such a tube is supernice for OTL as proposed allready but also can be used in SE. It would be very interesting to try wind your own transformer as the primary resistance is too low thus too easy to make! I am sure its going to be very hard to drive such beast, but as already stated, nothing is impossible.
If you like any help you can call me at 6977744232
Regards,
Panos
Geiasoy Gianni!
What a wonderfull tube this is! I never imagined you could find such tubes locally! Anyway such a tube is supernice for OTL as proposed allready but also can be used in SE. It would be very interesting to try wind your own transformer as the primary resistance is too low thus too easy to make! I am sure its going to be very hard to drive such beast, but as already stated, nothing is impossible.
If you like any help you can call me at 6977744232
Regards,
Panos
Agreed that the OPT will be a lot of work, and perhaps I should add that current sharing between the three cathodes within the envelope might be a concern - so individual cathode resistors would be preferable if cathode bias is used.
But not agreed that valves should be referred to John before proper disposal!
But not agreed that valves should be referred to John before proper disposal!
How about a parallel feed arrangement? The DC would then be dealt with by the choke. Although the bandwidth would be poor, a couple of big power supply chokes would get you started. With this you might be able to use a big mains toroid as the output transformer. You'd just have to figure out the proper turns ratio.
Fun!
Fun!
Actually both John and audiousername are quite incorrect- such tubes should be sent to me for proper and safe disposal.Agreed that the OPT will be a lot of work, and perhaps I should add that current sharing between the three cathodes within the envelope might be a concern - so individual cathode resistors would be preferable if cathode bias is used.
But not agreed that valves should be referred to John before proper disposal!
This tube is capable of 60 watts (8 ohms) in push-pull arrangement in an OTL with only one pair! This has the benefit of not having to engineer an OPT that otherwise does not exist. You can run plate voltages of only 150V and do rather well. You put a 5 ohm resistor in series with each cathode connection and that will help a lot to prevent current hogging (and will actually lower the output Z as a result). See http://www.diyaudio.com/forums/tubes-valves/161112-what-tubes-tube-amp.html for suitable schematic.
I know people that have used them in OTLs for years. Its quite linear, as that is a desirable characteristic in regulator tubes.
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