I made two amps on these Russian handsome men.
Both were push-pull. One in class A and with an output autotransformer in the cathode. The second in class B with an output transformer in the anode. If I undertook to do the amplifier again, the transformer would only make a cross section of 22 cm2 on toroidal amorphous magnetic cores. Previously it was very difficult to find them.
Both were push-pull. One in class A and with an output autotransformer in the cathode. The second in class B with an output transformer in the anode. If I undertook to do the amplifier again, the transformer would only make a cross section of 22 cm2 on toroidal amorphous magnetic cores. Previously it was very difficult to find them.
Forum member Atmasphere was generous enough to provide some further pointers via PM. I hope to complete a similar project in the near future. First hurdle was getting all the shop tools required to fabricate my own enclosure. With that recently accomplished, I look forward to amassing the required components so I can proceed. My aim is 6c33 push-pull, in the vicinity of 30 Watts, Class A using Lundahl iron. It will be part of a complete system overhaul, analog chain of which will be all DIY.
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Quite literally the tube was made for a socket design that simply does not support the filament current. As a result in the original Russian spec sheets it was recommended that the socket be replaced with the tube- every 750 hours
Of course the military could afford that. In the old days (we were the first to use the tube in the US) the socket was supplied with the tube. To get the best life:
1) make sure that the hole in the chassis is larger than the base of the tube to allow air flow
2) install Teflon washers between the chassis and the socket (assuming the socket is placed below the sheet metal) to allow air flow. Teflon will allow you to tighten the retaining nuts without fracturing the ceramic as easily. Use self-locking nuts but not NyLocs!
3) surround the socket location with holes in the sheet metal (or slots), also the bottom cover should have similar perforations.
4)Use silver solder (800 F) for the filament connections. Its a good idea to install Teflon tubing over the filament wiring to prevent it melting and shorting (Silicon insulation as Alastair pointed out is a good idea)
5) if you can fabricate a tin-plated heatsink for each filament pin on the socket they will last longer.
6) a fan is not a bad idea...
good tips,, i plan on using vertical wide copper shims as heater jumpers and hopefully help get rid of the heat somewhat..
No, this is not the same thing. But in the case of Lundahl it can also be a silicone steel and not an amorphous core. Therefore, you need to specify when buying.
From the advertising prospectus to the amorphous transformer.
Because of the low magnetostriction, they do not vibrate-they are completely noiseless.
Optimized for a record low internal resistance and low harmonic distortion.
Six times smaller losses in the nanocrystalline magnetic circuit (W / kg.) As compared to electrical steel (see Fig. 2) lead to a significant decrease in the impedance for the alternating current of the entire transformer as a whole as a voltage source, which is equivalent to a decrease in internal resistance and, accordingly proportional to the decrease in the value of the harmonic distortion voltage that occur on all conductors without exception and which are caused by the flow of a nonlinear load current.
The transformer on an amorphous alloy has an extremely rigid external characteristic and has practically no so-called "memory effect", which has a very favorable effect on both the static and dynamic stability of the output stage and, accordingly, contributes to a significant decrease in the nonlinear and intermodulation distortions of the UMZCH. And for transformers with a conventional steel magnetic core, the voltage on the active-capacitive load usually drops more than on the inductive load, so the external characteristic for the active-capacitive load is less linear than under the active-inductive load, then for transformers with an amorphous magnetic circuit, on the contrary. That is why the characteristic for an active-capacitive load, which is characteristic of rectifiers with capacitor filter-accumulators, is much more stringent.
Also in an amorphous transformer, because of the high permeability of the magnetic circuit, the value of the no-load current is several times smaller, and also less than the magnetic flux scattering field.
Another important advantage of a transformer with an amorphous magnetic core is its high efficiency and in a very wide range of loads, which makes it more efficient than a transformer made on a steel magnetic core, especially this advantage is great in classes B, AB and class D (T) (see Figure 3).
Thanks to three to ten times the large inductance of the primary winding, they have a huge overload capacity for infrasonic network switching interferences (see Fig. 4).
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If one wanted to undertake such a project, what would be the "best" sockets to start with?
I've got the itch to do an amplifier with these big bottles, and would likely mount the sockets in the middle of a grille intended to be used with 120mm computer case fans, and with active cooling a possibility.
I've got the itch to do an amplifier with these big bottles, and would likely mount the sockets in the middle of a grille intended to be used with 120mm computer case fans, and with active cooling a possibility.
Вest sockets with collet lamellae.
http://userweb.117.ne.jp/y-s/images/6C33C-7P-omote-s.jpg
http://userweb.117.ne.jp/y-s/images/6C33C-7P-omote-s.jpg
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The Teflon sockets should be avoided!!
Teflon is a very effective insulator against heat as well as electricity. This causes the otherwise very good connections in this socket to fail sooner than the less expensive ceramic sockets.
So not only are they a lot more expensive, they are also less reliable.
I doubt that anyone will come up with the idea of pulling these tubes out of the sockets on the move without allowing them to cool down completely first.
It is more difficult to find ceramics with collet lamellae, but they are. Most likely the temperature defect of Teflon in the sockets is greatly exaggerated. I did not use Teflon, but I also did not see the melted ones in the photo.
The 6S33S has a very high steepness, in Class A it is also greatly overheated, and the quiescent current will increase if you do not take special measures. Therefore, it is better not to load the anode at a maximum power of 60 watts. Do an automatic bias, it is also possible not to use 6.3V glow, but to reduce to 6V.
It is more difficult to find ceramics with collet lamellae, but they are. Most likely the temperature defect of Teflon in the sockets is greatly exaggerated. I did not use Teflon, but I also did not see the melted ones in the photo.
The 6S33S has a very high steepness, in Class A it is also greatly overheated, and the quiescent current will increase if you do not take special measures. Therefore, it is better not to load the anode at a maximum power of 60 watts. Do an automatic bias, it is also possible not to use 6.3V glow, but to reduce to 6V.
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Ralph is dead nuts on here. I've pulled many Teflon sockets out of otherwise perfectly functional equipment that just needed a ceramic socket.
The Chinese cheap septar sockets are to be avoided. The black spring tension clips on them fatigue and fall off!
Use these sockets if you can:
The only Teflon sockets that I've liked are the 4 pin jumbo ones.
The Chinese cheap septar sockets are to be avoided. The black spring tension clips on them fatigue and fall off!
Use these sockets if you can:
The only Teflon sockets that I've liked are the 4 pin jumbo ones.
Ralph is dead nuts on here. I've pulled many Teflon sockets out of otherwise perfectly functional equipment that just needed a ceramic socket.
The Chinese cheap septar sockets are to be avoided. The black spring tension clips on them fatigue and fall off!
Use these sockets if you can:
The only Teflon sockets that I've liked are the 4 pin jumbo ones.
+1 That's the best we've seen too.
Expensive and rare Russian ceramic socket for 6S33S https://01.img.avito.st/640x480/4084561901.jpg Of course this is Russian ceramics socket, and this is not Teflon from China or Japan. In Russia, Teflon has never been used for socket. I recently applied to a factory where military connectors are made. This plant can again make such socket, but they need volumes for the order. To order, you need at least 1000 pcs. but they can cover the collets with any metal, for example paladium or rhodium. Those that were in the photo above are also ceramic socket and also Russian, but they are heap for civilian applications. Cheap Russian ceramic socket for 6S33S https://media2.24aul.ru/imgs/547b40...a-plk7-1-dlya-6s33s-6s41s-pr-vo-4-4816305.jpg
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Would the "Sepatar" sockets listed on this page be suitable, or are they a different style?
Power Tube Sockets
Power Tube Sockets