Posting from smartphone because hotel internet is down. When I set out to choose a tube for my breadboard I created this monster spreadsheet that took several things into consideration including price and inventory. I am still waffling between using a single tube and seperate triodes and pentodes. The breadboard currently has a dual section tube and my choice IS the 9DX base. I got several samples of each one that is listed on the dollar menu. Many of these tubes were never used outside the USA so the best choice for a new board design is probably a 9A dual triode and a pair of 9AQ pentodes.
I collected some tubes today to feed to the hungry red board. The 6HD5 can substitute for the 6HJ5 in this board. I got some. Other good finds 18 X 6KN6 all of the twin plate variety. It seems that they dont work in ham RF amps. 9 X 6GJ5, 10 X 6HS5, 2 X 6GV5, 20 X 6GY5 and 10 X 16KA6. Some will go, some will glow.
Wish I were there, sounds like fun.
6HD5 10.0 approval rating
Do the doubled up guts in those 6KN6 tubes look like any tube you have ever seen before?
6GJ5... got pins? Those are nine pin, some kind of adapter?
6HS5? Yuk! Those are those beam triode thingies. Molotov cocktails maybe.
6GV5 9.0 approval rating
6GY5 9.9 approval rating
16KA6 8.5 approval rating
Back for more tomorrow I guess. Hope you've got some cash left.
6HD5 10.0 approval rating
Do the doubled up guts in those 6KN6 tubes look like any tube you have ever seen before?
6GJ5... got pins? Those are nine pin, some kind of adapter?
6HS5? Yuk! Those are those beam triode thingies. Molotov cocktails maybe.
6GV5 9.0 approval rating
6GY5 9.9 approval rating
16KA6 8.5 approval rating
Back for more tomorrow I guess. Hope you've got some cash left.
I looked up some images of two the 6KN6 versions. Looks like the dual version is a custom design, never seen any long skinny single pentodes like that. The tube vendors must have decided it was too expensive a construction later and redesigned it as a single. Unusual 400 mA max DC spec for a 30 Watt tube, but a 3 Amp filament to pay for it.
Attachments
Yes, I left when the hamfest officials threw us out about an hour after closing time today. Just got home and inventoried the stash. There is still money left in my wallet. I got a total of 200 tubes. 82 were from ESRC. The hamfest was just the delivery point. I also got some more 12 pin and 7 pin sockets from Stan. He had a box full of 6HD5's in dirty and broken boxes. I got a deal on all of them. The 6HJ5's all appear to be made by the same vendor. All are stamped "LYFA". The 6HD5's are either stamped "LYFA" or "LFA" and look to be from the same source. A few look different and appear to be Japanese.
There was a vendor selling components by the bag full and tubes by the box full. Friday I paid the asking $35 to fill a box with the biggest sweep tubes I could find.
18 X 6KN6 NOS Sylvania
9 X 6GJ5 NOS Sylvania
10 X 6HS5 NOS Sylvania
2 X 6GV5 NOS Sylvania
20 X 6CB6 NOS GE (small tubes to fill the box because no more big ones would fit)
I went back today and collected about 25 pounds of components, mostly electrolytic and silver mica capacitors for $22. I also negotiated a big box of tubes for $40
18 X 17JM6 NOS Sylvania
10 X 6GV5 NOS Sylvania
5 X 21HD5 NOS Sylvania
4 X 26HU5 NOS Raytheon
3 X 6AV5GA NOS Assorted
3 X 21JZ6 NOS Sylvania
3 X 17JN6 NOS Sylvania
1 Each NOS Assorted 21SJ6, 6GE5, 6HS5, 12GE5, 6HB5 22JV6, 22JU6
So not counting the 6CB6's I got 92 NOS sweep tubes for $75. Thats 76 cents each, so I can afford to blow up a few!
I also picked up 6 random used tubes from various vendors for $1 each or less.
I got some 6JD5's when they were on the $1 list. Same type of tube. I am convinced that these things can be used to make a really big amp. I have not learned how to tame them yet. They do make great oscillators.
No and the plates are close together. This could lead to hot spots.
I am not going to believe any approval ratings until I see the glow!
Nice finds! Lot of people at the Ham-fest? I should look into the one up around here. Can't wait to hear your testing results. Wait till the wife finds the stash tucked under the bed though. Better send them up here when you finish torturing them. Happy testing.
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Ever think of putting a tube graveyard in the back yard? Imagine some archeologist finding it someday. I've seen large beer bottle and wine bottle piles before, but Sweep tubes would take the cake.
Don
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Ever think of putting a tube graveyard in the back yard? Imagine some archeologist finding it someday. I've seen large beer bottle and wine bottle piles before, but Sweep tubes would take the cake.
Don
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I ordered a bunch of 16GY5's from Stan, will only have to deal with different filament voltage. So I get to keep the plate cap 
I will be interested to learn about the 9DX base options if it will improve the amp. I will be using 6DK6 to start with. If the gain is not enough I can drive it from my preamp.
Just a thought: What about adding a lightspeed attenuator for volume control?
I will be interested to learn about the 9DX base options if it will improve the amp. I will be using 6DK6 to start with. If the gain is not enough I can drive it from my preamp.
Just a thought: What about adding a lightspeed attenuator for volume control?
Check out the hammond 167P16 and 167M16 transformers for your filament voltages. Although you may have something available locally that fits the billI ordered a bunch of 16GY5's from Stan, will only have to deal with different filament voltage. So I get to keep the plate cap
I will be interested to learn about the 9DX base options if it will improve the amp. I will be using 6DK6 to start with. If the gain is not enough I can drive it from my preamp.
Just a thought: What about adding a lightspeed attenuator for volume control?
Couldnt you just string 2 6v heaters in series and convert to dc. Thats what 17.8- 16.9vdc depending on droop. Isnt that dead on the money?
Still where is everyone getting there tubes. Ive heard "dollar menu" , Stan, and a few other places. Still when i look, tube depot,the tube store, and antique radio supply, all want over $5 a tube regardless of model.
Eh guess im still mad after the 10 6HJ5 for $30 shipped left town.
Still where is everyone getting there tubes. Ive heard "dollar menu" , Stan, and a few other places. Still when i look, tube depot,the tube store, and antique radio supply, all want over $5 a tube regardless of model.
Eh guess im still mad after the 10 6HJ5 for $30 shipped left town.
Well where ever you got 10 6HJ5s for that shipped is the cheapest I have ever seen. Stan is ESRCvacuumtubes.com 6HJ5s are $4 each. He has the famous dollar menu.
ESRC in Florida is the main source they are using. Vacuumtubes.net is another.
Stuart
I think VacuumTubes.net were the ones that started the dollar menu thing a couple years ago. ESRC followed suit. VT even had boxes of tubes for cheaper prices, some like $0.35 a tube, but most of the interesting ones are gone now. I haven't seen a good tube sale from Antique for a couple of years now, I think I heard they changed hands there. They don't seem to be re-stocking any of the cheap tubes either. They did have good prices on some big sweep tubes though, during the last sale two years ago.
Stan is the owner operator of ESRC a buisness he took over from his father who started it in the 40's. He moved the business to Orlando when his father passed about 10 years ago. They were in Boynton Beach Florida and I used to buy tubes from his father. He still has the $1 list on his web site. The web site is Vacuum Tubes - Audio Tubes - ESRC Vacuum Tubes - Electron Tubes He has over 3 million tubes in stock and I go there whenever I can.
The $1 list started with Radio Electonic Supply corp. Their web site is Vacuum Tubes Radio Tubes - 5,000 different tubes in stock - Over 10 million tubes!. There is no longer a dollar list there, but some tubes are still priced at $1 on their price lists. Not all of them are in stock though. They bought out the NOS tube inventory from a DIY electronics shop (Angela?), kept what they wanted and sold the rest in the original boxes. I got a box full of 6BQ6GA's for under $1 each. Yes, the good stuff was gone in about 3 days.
I don't know where you can get them for $3, but they are $4 at ESRC and VT.net. 6HD5's are listed for $2 at VT.net but they have none in stock. I got all that Stan had, but he will get more. He sells them for $5.
I decided to pay the extra money for 6GY5's. It's still cheaper than adding another transformer.
It seemed to me that there were less people than last year. Hamfests are a hit or miss thing. I go to Orlando every year since the Miami hamfest died. Sometimes I find lots of good tubes, sometimes I don't. I saw a "working" Heathkit 0-400 volt power supply for $5. I didn't buy it since I have several HV power supplies already but I did but a Kepco 0-50 volt 2 amp supply for $10 just to light the oddball tubes. I also look for stuff that can be recycled for chassis and stuff with useful transformers that goes for cheap.
The two plates are actually stamped from a single sheet and they are joined at a common seam. I bet that is where the glow starts. I am guessing that the reason for doing it this way is to allow two cathodes to support the high peak current. After looking at all 18 tubes it looks like these were a nightmare to assemble so the dual design was abandoned. Some have obvious alignment issues. They won't live long.
My list only has 21 numbers, I must have missed a few.
9DX: "My list only has 21 numbers, I must have missed a few. "
There are a couple that aren't on the GE manual 9DX list. 6/10JA8 and 6KT8 (which is really 9QP based, but compatible) I don't think I included 7716 in my count, sorta similar to a 6CX8 but 13.6 V filament and a higher Mu triode.
Let's see, A counting we shall go, ....
6AU8 6AW8 6BA8 6BH8 6CX8 6EB8 6GN8 6HF8 6HZ8 6JA8 6JE8 6JL8 6JT8 6JV8 6KR8 6KS8 6KT8 6KV8 6LB8 6LF8 6LQ8 6LY8 6MV8 10JY8 10LW8 10LZ8 7716
27!! (not counting all the filament voltage variants)
Some of the 10 or 11 Volt ones I figure might work out well with 21 V filament sweeps.
There are a couple that aren't on the GE manual 9DX list. 6/10JA8 and 6KT8 (which is really 9QP based, but compatible) I don't think I included 7716 in my count, sorta similar to a 6CX8 but 13.6 V filament and a higher Mu triode.
Let's see, A counting we shall go, ....
6AU8 6AW8 6BA8 6BH8 6CX8 6EB8 6GN8 6HF8 6HZ8 6JA8 6JE8 6JL8 6JT8 6JV8 6KR8 6KS8 6KT8 6KV8 6LB8 6LF8 6LQ8 6LY8 6MV8 10JY8 10LW8 10LZ8 7716
27!! (not counting all the filament voltage variants)
Some of the 10 or 11 Volt ones I figure might work out well with 21 V filament sweeps.
Roy and Dale from RES (vacuumtubes.net) bought out the tube stock from Radio Daze about a year or two ago. The pre-packaged overstock specials showed up on the RES web site shortly after their purchase of the Radio Daze stock.
Make that 29! I found two more, sorta .... They're even on the $1 list too.
6ET7 and 6KU8 on the 9LT base. These have a pentode that is pin compatible with the 9DX base, but two diodes in place of the triode that's on the 9DX base.
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make that 30!! I'm on a roll here: 6JG5 on the 9SF base is pin compatible with 9DX but only has the pentode alone. And it's on the 1$ list too.
6ET7 and 6KU8 on the 9LT base. These have a pentode that is pin compatible with the 9DX base, but two diodes in place of the triode that's on the 9DX base.
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make that 30!! I'm on a roll here: 6JG5 on the 9SF base is pin compatible with 9DX but only has the pentode alone. And it's on the 1$ list too.
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All of the tubes on my list are on your list. I was missing the 6KT8 from my list and I didn't include tubes that weren't available with 6 volt heaters. Some builders have a fear of anything that doesn't start with 6. Many builders don't like plate caps either, but it seems that others do. Get used to them if you want to go beyond 100WPC from a pair of tubes.
The 6JG5 is a 6GN8 with the triode missing. I have some of both from the AES sale two years ago. I think we discussed this tube and a few others from this list back then. I got some of these tubes back in that sale. 9 of these are (or were) on the dollar menu at one time so I got at least 10 of each kind. The 6LQ8 was used as the driver in my version of the G1=G2 experiment. It is still used in my breadboard since the breadboard evolved from those experiments.
http://www.diyaudio.com/forums/tube...ed-drive-strawman-design.html?highlight=G2=G1
They told me that when I bought the tubes but I couldn't remember who thay bought out.
I thought I was safe with the wife 1200 miles away, but my mother passed away this morning (expected, she was 90 and in poor health) so I just got a ticket for Sherri to fly home TOMORROW! I guess the experiments are on hold for a while and I got to find a place to hide all the stuff that is currently scattered all over the house!
