Boris_The_Blade said:
A really good way to get into good-sounding NOS tubes, too. These are an exact functional equivalent to the 6V6, and you can usually find them for $10 or less, each, for NOS tubes.
Most of these were made by Sylvania... and IME, they usually have VERY close tolerances. I find that most of them automatically match within a few percent, without having to cherry-pick matched sets...
Regards,
Gordon.
GordonW said:
These are an exact functional equivalent to the 6V6, and you can usually find them for $10 or less, each, for NOS tubes.
Most of these were made by Sylvania... and IME, they usually have VERY close tolerances. I find that most of them automatically match within a few percent, without having to cherry-pick matched sets...
Regards,
Gordon.
Gordon,
A look at the 7C5 data sheet indicates g2 limits akin to those of the 6AQ5 (yet another 6V6 family member).
Were Locktal based tubes made anywhere other than Sylvania's Emporium, PA, plant? AFAIK, not in the U.S.A.
Eli Duttman said:
Somewhere, I have a 7C5 datasheet that looks more like a 6V6.
In any case... I've repeatedly and deliberately run them at levels like a 6V6... 300-310v on the plates and screens, cathode bias, so it's like 275v differential between cathode and plate. None has ever complained. Sound EXCELLENT...
EDIT: Found it. It's on Pete Millett's Sylvania manual page. http://www.pmillett.com/tubedata/Sylvania/1951/sylvania_1951.pdf
This manual shows 285V as permissible. I over-run that a bit, but not more than 10% over...
Regards,
Gordon.
Eli
I've seen you make this comment before. I've also seen someone post that Sylvania used 6V6 parts and just stuffed them in a different bottle. I wouldn't know, but I do know I built Poinzs' latest but with the 7C5 (300 ohms plus diode for triode connection). I've had no problems. In fact, its the best amp I've ever had in my house and seems just made for my Lowthers.
Bruce Anderson
I've seen you make this comment before. I've also seen someone post that Sylvania used 6V6 parts and just stuffed them in a different bottle. I wouldn't know, but I do know I built Poinzs' latest but with the 7C5 (300 ohms plus diode for triode connection). I've had no problems. In fact, its the best amp I've ever had in my house and seems just made for my Lowthers.
Bruce Anderson
Bruce Anderson said:
That which is published and that which actually is frequently are different. See Gordon's link to Pete Millett's site.
I'd be surprised if Sylvania did anything other than use the exact same "cages" in both 6V6s and 7C5s. After all, they were in business to turn a profit. Given my belt and suspenders nature about things electrical, that French data sheet makes me raise the yellow flag.
How about an EL84 sub?
Great thread. I'll check them out. I have an old 6V6 amp chasis that needs O/H anyway so why not!
Pardon the partial threadjack; I sense we are almost done here. Is there a similarly clever alternative for the ever more expensive EL84? I have a really clean Magnavox PP EL84 amp I picked up for the good EL84s and have since put them to good use. I'd like to find an inexpensive 9 pin power pentode alternative for that chassis and I wouldn't mind differing base connections.
Great thread. I'll check them out. I have an old 6V6 amp chasis that needs O/H anyway so why not!
Pardon the partial threadjack; I sense we are almost done here. Is there a similarly clever alternative for the ever more expensive EL84? I have a really clean Magnavox PP EL84 amp I picked up for the good EL84s and have since put them to good use. I'd like to find an inexpensive 9 pin power pentode alternative for that chassis and I wouldn't mind differing base connections.
GordonW said:
The RCA data sheet I have for 7C5, dated June 20, 1947, expressly says "maximum ratings and typical operating conditions for the 7C5 are the same as those for type 6V6".
The Tung Sol data sheet I have that is dated 1952, lists a max plate voltage at 315, G2 at 285, Pd 12 watts, G2d at 2 watts, and max H-K 90 volts for type 7C5.
It has a complete set of curves for 7C5, and also implies there was a 12 volt version, numbered 14C5.
Win W5JAG
Re: How about an EL84 sub?
6GK6 looks very similar to me, but it does have a different pin out. It comes in a bunch of filament voltages (as does 6BQ5).
And there is always 6094 or 7757, but they are usually expensive, unless you get lucky.
That funky 6P1P Russian analog of 6AQ5 and 6V6 has a 9 pin base. I learned that the hard way.
Win W5JAG
Captn Dave said:
6GK6 looks very similar to me, but it does have a different pin out. It comes in a bunch of filament voltages (as does 6BQ5).
And there is always 6094 or 7757, but they are usually expensive, unless you get lucky.
That funky 6P1P Russian analog of 6AQ5 and 6V6 has a 9 pin base. I learned that the hard way.
Win W5JAG
Dave,
Decent EL84s need not be especially expensive. Jim McShane charges $21.50/pair for the Russian 6П14П-ЕВ (6p14p-ev), AKA EL84M. The variant is a genuine 7189 equivalent, with decent sonics. There are no questions about being tough enough for service in your vintage Magnavox equipment.
I used 7C5s in an el-Leako documented at
http://www.audiophiletalk.com/cgi-bin/yabb2/YaBB.pl?num=1126228937/660
I managed to get 10 NOS for $20! Sounds good too.
http://www.audiophiletalk.com/cgi-bin/yabb2/YaBB.pl?num=1126228937/660
I managed to get 10 NOS for $20! Sounds good too.
one sustitute less price for the EL84.
One good sustitute the low price for EL84/6bq5....
The winer is...8BQ5
Acept the at the 6,3 to 8v in filaments.!!!
I use this for much years in radio, guitar ...and other, goog direct sustitute or ajust the circuit for it.
And low price, and low noise for example in General Electric green labels.
Good resource
Hummmmmm i see a probe this whit singles OTL's and direct output whit 800 /2000 ohms
fmk-spain-madrid.
One good sustitute the low price for EL84/6bq5....
The winer is...8BQ5
Acept the at the 6,3 to 8v in filaments.!!!
I use this for much years in radio, guitar ...and other, goog direct sustitute or ajust the circuit for it.
And low price, and low noise for example in General Electric green labels.
Good resource
Hummmmmm i see a probe this whit singles OTL's and direct output whit 800 /2000 ohms
fmk-spain-madrid.
Tung-Sol 7C5 Datasheet
Sylvania 7C5 Datasheet
Raytheon 7C5 Datasheet (tentative)
RCA 7C5-LT Datasheet (tentative)
Brimar 7C5 7C6 6BW6 Datasheet
That's pretty much what's out there, from Frank's..
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