fsjonsey said:
That is very odd!
An externally hosted image should be here but it was not working when we last tested it.
7N7
You let them know too much already 
Hey Tubelab,
I usually just do a lot of reading but I had to chime in on the D&A Phanton 500! God that brings back a lot of old memories. I had one of the first ones ever made which had 6 6LQ6's driving 6! I would drive it with either a re-tubed D&A Maverick or a 50 watt modulator and man would that thing swing! 1KW peak was the norm with a new set of tubes, but I must admit the tubes lasted from a day to a month depending on how much beer was involved. That thing would literaly stop the clock on my microwave, I mean re-set it to all zero's! Of course we where all dumb kids back then. Sorry for the off topic but I had to tell you that story.
6AF9 = 6R4P = EFL200
The basic version is actually the 300mA series heater PFL200. It is a fairly common cheap tube in Europe.
The reason they are so cheap is the 'odd' 'decal' base (10 pins), made for later european hybrid (semiconductor + tube) TV sets. There are a number of other tubes in this '200' series, PCL200, PCH200, PCF200 and 201. The (not as widely used) PCL200 and PCF200 triode-pentode combos are interesting, but there is no high power BPT or pentode combo in this series as vertical deflection and audio were already handled by semiconductors, and horizontal deflection used the already established PL504 or 509.
The EFL200 holds two dissimilar pentodes, generally used for IF amplificatio (small signal pentode) and video output (power pentode). Both were intended for operation at relatively low anode voltages.
The power pentode, alas, has a maximum dissipation of 5.1W which somewhat limits it's usefulness, but it's quite linear and like all later 'video' pentodes has very high gm. It could probably be used to build a decent class B PP amp, or maybe a totem-pole high-Z headphone OTL amp. Like most video pentodes, it is very easy to drive, only a couple of volts are needed.
The small signal pentode section is also quite usable, but limited to 1.5W Pd.
As far as I know, no-one has yet traced triode curves for these, but looking at the data, they will propbably be quite decent, although unusual in the sense that both sections will have a rather high-ish mu of about 38 or so, not a typical situation. This also means that the Rp of the power section when connected in triode will not be especially low. However, the relatively high combined amplification factor alowes for higher NFB in some configurations, if one likes such a thing, of course
The basic version is actually the 300mA series heater PFL200. It is a fairly common cheap tube in Europe.
The reason they are so cheap is the 'odd' 'decal' base (10 pins), made for later european hybrid (semiconductor + tube) TV sets. There are a number of other tubes in this '200' series, PCL200, PCH200, PCF200 and 201. The (not as widely used) PCL200 and PCF200 triode-pentode combos are interesting, but there is no high power BPT or pentode combo in this series as vertical deflection and audio were already handled by semiconductors, and horizontal deflection used the already established PL504 or 509.
The EFL200 holds two dissimilar pentodes, generally used for IF amplificatio (small signal pentode) and video output (power pentode). Both were intended for operation at relatively low anode voltages.
The power pentode, alas, has a maximum dissipation of 5.1W which somewhat limits it's usefulness, but it's quite linear and like all later 'video' pentodes has very high gm. It could probably be used to build a decent class B PP amp, or maybe a totem-pole high-Z headphone OTL amp. Like most video pentodes, it is very easy to drive, only a couple of volts are needed.
The small signal pentode section is also quite usable, but limited to 1.5W Pd.
As far as I know, no-one has yet traced triode curves for these, but looking at the data, they will propbably be quite decent, although unusual in the sense that both sections will have a rather high-ish mu of about 38 or so, not a typical situation. This also means that the Rp of the power section when connected in triode will not be especially low. However, the relatively high combined amplification factor alowes for higher NFB in some configurations, if one likes such a thing, of course
tubelab.com said:
There. I fixed it for you.
Let's do mention them. So the price goes up. Better that than suppliers who have these in stock decide that since these types aren't moving even at under-a-buck prices that the warehouse space would be better utilized for something else, and the whole lot become trashed. That'll make them unobtanium just as surely as the DiY-ers buying up all the stock.
The 6BQ6 is a fine sounding VT, light 'em up and enjoy what's essentially a more powerful 6V6.
Miles Prower said:
Let's do mention them. So the price goes up. Better that than suppliers who have these in stock decide that since these types aren't moving even at under-a-buck prices that the warehouse space would be better utilized for something else, and the whole lot become trashed. That'll make them unobtanium just as surely as the DiY-ers buying up all the stock.
The 6BQ6 is a fine sounding VT, light 'em up and enjoy what's essentially a more powerful 6V6.
BUMP
I just got back from Dayton, and, unless I wasn't paying attention in years past, there were a lot more tubes for sale this year than in years past. They were downright abundant.
NOS 6AV5GA's were $0.50 - $2.00 depending on where you were in the flea market, ditto for 6BQ6GT and 6BG6GT; I got NOS 6K6GT's for $0.50 to $4.00; NOS 6W6GT, 6F6GT, 6Y6GA, etc., for $0.50 to $1.00.
I saw NOS 5881 for $20-22, didn't buy any of these. I got a pair of NOS blackplate RCA 6V6GTA (for those that care about the color of the plates) for $35.00.
USA 2A3's, used, were $30 ish, used 45's were $15 to $30, NOS $70.00. NOS 5842's were $10, gold pin dual marked 5842/417A variants were $12.
I loaded down like a pack mule, but left plenty for others. Lots of big triodes and small signal tubes at good prices as well.
Win W5JAG
edit: the only tube I could not find, that I was on the lookout for, were 5992. Saw 6384's and the rectifier and 6080 Bendix variants, but no 5992. Went to Fair Radio Sales on Thursday, and they didn't have any, either.
Well, I just got back from Dayton too. I loaded up on NOS tubes that I use both in equipment and building on Thursday for 50¢ each.
Just for kicks I brought a pair of original WE 300B's from the 50's in original boxes to sell. Everyone choked on the asking price of $2000. But one guy did give me $1500 for the pair. I probably sold them too cheap. Also had some nice Hickok testers. Lots of lookers, but no takers.
George, I was wondering where you were. I had some nice 10ufd/450 volt PP caps available.
Victor
Just for kicks I brought a pair of original WE 300B's from the 50's in original boxes to sell. Everyone choked on the asking price of $2000. But one guy did give me $1500 for the pair. I probably sold them too cheap. Also had some nice Hickok testers. Lots of lookers, but no takers.
George, I was wondering where you were. I had some nice 10ufd/450 volt PP caps available.
Victor
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