I need to socket a Novar tube PCB, but B9E sockets are rare and very pricey.
However B9D Magnoval is in production and available very cheap.
These two bases have identical circle diameters pin center to pin center of 17.45 mm.
But the pins diameters differ by about .26 mm. Novar are 1.02 and Magnoval is 1.27 mm.
I'm thinking I should be able to plug a Novar tube into a Magnoval socket, there should be enough closure in the springs to make contact no? its only .26 mm short.
As long as I never plug a Magnoval tube into it which would then stretch out the springs making the socket too loose for Novar.
For Novar tubes do fellow DIY'ers get good enough contact using the widely available B9D sockets?
However B9D Magnoval is in production and available very cheap.
These two bases have identical circle diameters pin center to pin center of 17.45 mm.
But the pins diameters differ by about .26 mm. Novar are 1.02 and Magnoval is 1.27 mm.
I'm thinking I should be able to plug a Novar tube into a Magnoval socket, there should be enough closure in the springs to make contact no? its only .26 mm short.
As long as I never plug a Magnoval tube into it which would then stretch out the springs making the socket too loose for Novar.
For Novar tubes do fellow DIY'ers get good enough contact using the widely available B9D sockets?
This website seems to have them at =$4.95 -
Cinch 9 Pin "Novar" Socket Under Chassis Style (Item: NOS-SKT-53) - Radio Daze LLC
Cinch 9 Pin "Novar" Socket Under Chassis Style (Item: NOS-SKT-53) - Radio Daze LLC
czhstore2013 lists some ceramic gold plated sockets on Ebay for Novar 7868, 6LQ6 and EL509. 2 FOR $10.
2PCS 9PIN CERAMIC TUBE SOCKET For EL509 7868 6LQ6 EL504 EL502 DIY Gold Plated | eBay
However, EL509 is Magnoval. I tried some, and the Novar tubes just fall out of the sockets. I was able to crunch the pins together with needle-nose pliers after removing the pins, re-assembling and then they work OK. But what a PITA!
ESRC had some Chinese Novar sockets that worked OK, I had bought some a while back. But I have no idea which supplier they got them from.
You can search Ebay for 7868 or 6LQ6 sockets, but most of them are going to be Chinese magnoval/novar(not!) sockets. Maybe someone has found a workable source?
You can also buy individual socket pins for the Novar/Noval pins at Mouser. Keystone #1434 at Mouser I heard. If someone would make a small round PC board to mount them on, we could make our own (expensive) sockets. Male pins are available on Ebay, Tubemalls:
100Pieces Gold plated tube adapter pins DIY for 12AX7 12AU7 6BQ5 ECC88 EL84 6922 | eBay
Something like this maybe:
1piece* 9pin converter for CV4035 CV4034 Fly pins adapter | eBay
Sombody makes a "Novar" socket for this:
1PC 9pin tube tester saver for 7868 6GT5 | eBay
or this:
1pc Gold 9pin Experiment board for test 7868 6GT5 EL508 EL530 ect | eBay
except EL508 is Magnoval
2PCS 9PIN CERAMIC TUBE SOCKET For EL509 7868 6LQ6 EL504 EL502 DIY Gold Plated | eBay
However, EL509 is Magnoval. I tried some, and the Novar tubes just fall out of the sockets. I was able to crunch the pins together with needle-nose pliers after removing the pins, re-assembling and then they work OK. But what a PITA!
ESRC had some Chinese Novar sockets that worked OK, I had bought some a while back. But I have no idea which supplier they got them from.
You can search Ebay for 7868 or 6LQ6 sockets, but most of them are going to be Chinese magnoval/novar(not!) sockets. Maybe someone has found a workable source?
You can also buy individual socket pins for the Novar/Noval pins at Mouser. Keystone #1434 at Mouser I heard. If someone would make a small round PC board to mount them on, we could make our own (expensive) sockets. Male pins are available on Ebay, Tubemalls:
100Pieces Gold plated tube adapter pins DIY for 12AX7 12AU7 6BQ5 ECC88 EL84 6922 | eBay
Something like this maybe:
1piece* 9pin converter for CV4035 CV4034 Fly pins adapter | eBay
Sombody makes a "Novar" socket for this:
1PC 9pin tube tester saver for 7868 6GT5 | eBay
or this:
1pc Gold 9pin Experiment board for test 7868 6GT5 EL508 EL530 ect | eBay
except EL508 is Magnoval
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The Wikipedia page on tube sockets has this link to a forum discussion in which the experiences with using a B9D tube socket for Compactrons are not good: Antique Radio Forums • View topic - Novar vs Magnoval Vacuum Tube Sockets
Looking at the Chinese ceramic Magnoval/Novar(not!) sockets and some similar Chinese ceramic Compactron sockets, it looks like the Compactron pins would fit the "Magnoval/.." sockets. If one could order the "Magnoval/.." 9 pin sockets without pins, and order Compactron socket pins (only), they could be combined to make valid Novar sockets.
Getting socket pins -out- of a ceramic socket are a big pain however, as I found from modifying the "Magnoval/.." socket pins to fit Novar tube pins with a pliers. Also, getting the re-inserted pins to -stay- in the socket again is a pain, microsurgery with needle-nose needed to get the locking tabs to work again.
To confuse matters further, it seems that EH is making a 7868 tube with Magnoval pins now. (7868 was originally Novar) The Novar socket situation may become utterly hopeless soon. 6LQ6/6JE6 and 6GT5 are still Novar (have been used for audio). (many other Novar Sweep tubes around: 6JB6, 6JR6, 6GT5, 6KV6, 6JG6, 6JT6, 6JF6, 6JU6, 6KM6, 6MC6, 6ME6, 6LZ6, 6MJ6, 6GJ5, 6LR8, 6KY8, 6GF7 )
Getting socket pins -out- of a ceramic socket are a big pain however, as I found from modifying the "Magnoval/.." socket pins to fit Novar tube pins with a pliers. Also, getting the re-inserted pins to -stay- in the socket again is a pain, microsurgery with needle-nose needed to get the locking tabs to work again.
To confuse matters further, it seems that EH is making a 7868 tube with Magnoval pins now. (7868 was originally Novar) The Novar socket situation may become utterly hopeless soon. 6LQ6/6JE6 and 6GT5 are still Novar (have been used for audio). (many other Novar Sweep tubes around: 6JB6, 6JR6, 6GT5, 6KV6, 6JG6, 6JT6, 6JF6, 6JU6, 6KM6, 6MC6, 6ME6, 6LZ6, 6MJ6, 6GJ5, 6LR8, 6KY8, 6GF7 )
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I have found a source of cheap "Magnoval" sockets, ceramic, most likely Chinese manufacture, where the customer comments are that Magnoval tubes -don't- fit into them! Too tight.
I've ordered a few sockets to try out for Novar use. Will have them next week I hope. I'll report back.
I've ordered a few sockets to try out for Novar use. Will have them next week I hope. I'll report back.
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I was buying new production Chinese Novar PCB sockets from ESRC about 15 years ago. Either they still exist somewhere, or the demand wasn't high enough and they quit making them.
I was planning to sell these Spud PC boards, but that project died due to lack of time and someone else beating me to market with the same design. I had purchased a big box full (over 100) of 6LR8's and I proceeded to test every tube in this board. I also performed some of my usual stress tests. The sockets did get a bit loose after about 75 insertions each, but that happens with the other Chinese sockets too.
As someone stated a Magnoval will not go into these sockets without undue force. If such a force is applied, a Novar tube will no longer make reliable contact, and fall out of the socket if the board is inverted.
I was planning to sell these Spud PC boards, but that project died due to lack of time and someone else beating me to market with the same design. I had purchased a big box full (over 100) of 6LR8's and I proceeded to test every tube in this board. I also performed some of my usual stress tests. The sockets did get a bit loose after about 75 insertions each, but that happens with the other Chinese sockets too.
As someone stated a Magnoval will not go into these sockets without undue force. If such a force is applied, a Novar tube will no longer make reliable contact, and fall out of the socket if the board is inverted.
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The "Novar" (Chinese, ceramic) sockets I got from ESRC years ago fit Novar tubes reasonably well also. But not firmly tight.
However, some further testing with a Noval pin found that about 1 in 3 sockets had a loose socket pin for Noval/Novar pins. So I always check those sockets meticulously for faults. They are fixable with a tiny screwdriver at least.
The source of "tight" Magnoval sockets that I just found look just like the ESRC sockets from back then. I will test them thoroughly when they arrive.
However, some further testing with a Noval pin found that about 1 in 3 sockets had a loose socket pin for Noval/Novar pins. So I always check those sockets meticulously for faults. They are fixable with a tiny screwdriver at least.
The source of "tight" Magnoval sockets that I just found look just like the ESRC sockets from back then. I will test them thoroughly when they arrive.
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If one could use the Russian ceramic Magnoval sockets, do use them and leave the limited “real” Novar supply to folks who must use them. If you need Novars, look no further, or settle for “immitations” - get these from Radio Daze while they still have ‘em. I bought some from Radio Daze and I’m very happy with these Cinch “real NOS” Novar sockets.
A quick trip through my junk collection reveals two PC board sockets for the Novar, and one chassis mount. The middle one is the Chinese socket that I mentioned in the last post. It can be seen that the pin sockets have the least tension in them and the tube is fairly easy to put in and pull out compared to the other two.
I have no idea where the other sockets came from, but the chassis mount is marked "CINCH" and the other is marked 312 which is Sylvania's EIA code, so they were probably OEM made for use in a Sylvania TV set.
I have no idea where the other sockets came from, but the chassis mount is marked "CINCH" and the other is marked 312 which is Sylvania's EIA code, so they were probably OEM made for use in a Sylvania TV set.
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The "Novar" (Chinese, ceramic) sockets I got from ESRC years ago fit Novar tubes reasonably well also. But not firmly tight.
However, some further testing with a Noval pin found that about 1 in 3 sockets had a loose socket pin for a Noval/Novar pin. So I always check those sockets meticulously for faults. They are fixable with a tiny screwdriver at least.
The source of "tight" Magnoval sockets that I just found look just like the ESRC sockets from back then. I will test them thoroughly when they arrive.
I'm only aware of 7868, 6LQ6/6JE6 and 6GT5 Novar tubes being used for audio in the past. So with the EH 7868 Magnoval version out now, the need for Novar sockets has probably evaporated.
But for DIY amps, there are lots of cap-less Novar Sweep tubes out there, suitable for modest power Amps: 12GT5, 17JT6, 22JR6, 22JG6, 17KV6, 6LR8, 6KY8, 6GF7
However, some further testing with a Noval pin found that about 1 in 3 sockets had a loose socket pin for a Noval/Novar pin. So I always check those sockets meticulously for faults. They are fixable with a tiny screwdriver at least.
The source of "tight" Magnoval sockets that I just found look just like the ESRC sockets from back then. I will test them thoroughly when they arrive.
I'm only aware of 7868, 6LQ6/6JE6 and 6GT5 Novar tubes being used for audio in the past. So with the EH 7868 Magnoval version out now, the need for Novar sockets has probably evaporated.
But for DIY amps, there are lots of cap-less Novar Sweep tubes out there, suitable for modest power Amps: 12GT5, 17JT6, 22JR6, 22JG6, 17KV6, 6LR8, 6KY8, 6GF7
I sold all the 6LR8's years ago. I still have some 6KY8's and 6GF7's and maybe a few of the others. I have a big bag (maybe 100) of the white ceramic Novar sockets, a small bag of the CINCH Novar sockets, but only one chassis mount socket.
I have come to realize that I have far more projects than life expectancy left, so a lot of my "excess" will soon be sold to fund the fun projects.
Anyone up to building a monophonic 200 watt SE amp that uses an 833A on about 2 KV. I still have a few used tubes somewhere, an OPT (only one) and a power transformer. I had forgotten about them until I was moving stuff around in the basement in case IDA treated us badly. We did get some flooding, but no water intrusion into the house or basement. I haven't ventured into the outdoor shed yet.
I have come to realize that I have far more projects than life expectancy left, so a lot of my "excess" will soon be sold to fund the fun projects.
Anyone up to building a monophonic 200 watt SE amp that uses an 833A on about 2 KV. I still have a few used tubes somewhere, an OPT (only one) and a power transformer. I had forgotten about them until I was moving stuff around in the basement in case IDA treated us badly. We did get some flooding, but no water intrusion into the house or basement. I haven't ventured into the outdoor shed yet.
If I had an old amp to restore that took 7868’s I’d probably yank the sockets and put in octal wired for 7591. And use the 7591 tubes on hand. That would give a few more sockets for experiments. Doubt I’m ever going to build something ‘serious’ using novars but there are cheap tubes to play with.
The Novar sockets I got from ESRC years back had a retainer ring included for chassis mounting. (1st pic) So you may have a bag of retainer rings in there somewhere.
I still have a bunch of Novar Sweeps from way back ($1 days), so hope to get an amp together soon. Easy to make them look like "Octal" tubes. (pics)
I still have a bunch of Novar Sweeps from way back ($1 days), so hope to get an amp together soon. Easy to make them look like "Octal" tubes. (pics)
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Yes I have some of the rings. I don't have as many rings as sockets. I didn't always get the rings since I never use them, but I probably have a few hundred.
I like the look of your "octal 6HJ5's" and may make some one day. Publish the parts list if you have one, especially the gold shiny sleeve.
I never collected many Novar sweeps because of the sockets, but I do have some in a box somewhere. Ditto Loctals, but Stan did have some Chinese loctal sockets too in his last few years. I also sold my big bag of Nuvistors many years ago for far less than they would go for today.
I like the look of your "octal 6HJ5's" and may make some one day. Publish the parts list if you have one, especially the gold shiny sleeve.
I never collected many Novar sweeps because of the sockets, but I do have some in a box somewhere. Ditto Loctals, but Stan did have some Chinese loctal sockets too in his last few years. I also sold my big bag of Nuvistors many years ago for far less than they would go for today.
The first one I made (1st pic) was just for a Novar socket saver and possible bias current test adapter. I used a 7868 to 7591 adapter (2nd pic) to make it with a Novar socket up top and long pins (4th pic) soldered to it. I used a pin straightener (5th pic) (1/4 inch thick) to hold the pins in position. A tube in the socket keeps the pins aligned there while soldering the socket to the pin array. I Super glued the fiberglass disk to the "gold" ring on the bottom. A set screw holds the socket in place up top, but could be done better with a lathe to indent the ring better. Later I found there was already such a Novar socket saver product on Ebay (3rd pic).
I liked the look of just putting them on a Novar tube (looking like a fancy Octal tube). So I made some more. This way is expensive however. One could just use a 30 mm ID brass tube to make the rings. A lathe would be a big help, but a saw and file should work too.
I haven't seen any version on Ebay for Compactrons yet. I cheated on the Compactron versions here for the 6HJ5 by using a Pomona SS-12 socket saver inserted into the same gold (brass) ring and the set screw to hold it.
I plan to make some fiberglass/phenolic disks with 12 pin holes using the pin straightener for a pin hole drill guide. Then cut the fiberglass into a circle and file to fit the ring, or use a lathe to finish. Then just solder pins to a Compactron socket using the same technique with the pin straightener holding the pins.
You can make bias current test adapters this way easily too. (6th pic) There already is one on Ebay for ( I assume still Novar)/7868.
1piece*Gold plated 7591(Adapter top) TO RCA 7868 tube converter adapter | eBay
1PC 9pin tube tester saver for 7868 6GT5 | eBay
100Pieces Gold plated tube adapter pins DIY for 12AX7 12AU7 6BQ5 ECC88 EL84 6922 | eBay
1pc Gold plated Tube amp bias tester for 7868 Tube amp | eBay
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