Yes, you can make a single-ended amp with them. Heck, you can make a single ended amp with any amplification device - even a 12AX7 if you felt like it.
You can have a look at the Eimac datasheet on Frank Phillipse's site here. My concern is that the construction of a 450TL amp is non-trivial and involves dangerous voltages - probably several thousand volts
You can have a look at the Eimac datasheet on Frank Phillipse's site here. My concern is that the construction of a 450TL amp is non-trivial and involves dangerous voltages - probably several thousand volts
It can be several 100.
Day, believe me. These things need lots of volts to work well. Another thing of note - there don't seem to be normal anode characteristic curves available, so you'll have to derive them from the Eimac constant current characteristics, which is a bit of a pain. Also a pain is providing a 90W filament supply. But nowhere near the pain of being shocked by a several kV power supply!
In the interests of your safety, I would suggest working with something less dangerous - someone with sufficient knowledge to be safe with such high voltages probably would not need to ask how to design a single ended amplifier.
In the interests of your safety, I would suggest working with something less dangerous - someone with sufficient knowledge to be safe with such high voltages probably would not need to ask how to design a single ended amplifier.
day said:
I'm not familiar with these valves. I'll have a look at the datasheets and get back to you.
EDIT: I had a quick look at the datasheets. These are little metal thingies, yes? They basically require forced air cooling and are sort of dangerous too since (I think) that the external radiators are in fact connected to the anode - and are thus at the potential of the HT.
That is a nice lookiing amp 
I'll hazard a guess and say - SE 2A3?
Might I suggest trying to get a hold of some RF double tetrodes like 829B, QQV03-20, QQV07-50, YL1071 etc... (the all glass things with prongy anode connectors on top) if you're looking for some nice valves that don't cost the earth.
If you must have single-ended, the problem is that most higher powered amps, say >10W will require very dangerous voltages.
I'll hazard a guess and say - SE 2A3?
Might I suggest trying to get a hold of some RF double tetrodes like 829B, QQV03-20, QQV07-50, YL1071 etc... (the all glass things with prongy anode connectors on top) if you're looking for some nice valves that don't cost the earth.
If you must have single-ended, the problem is that most higher powered amps, say >10W will require very dangerous voltages.
No need to apologise for your English, it's much better than my Thai
Pentodes and tetrodes can be very good, it's just that they tend to produce too much distortion and have too high an output impedance on their own - so they need some negative feedback to work well (preferably of the local kind). In any case, some tetrodes can make very nice triodes.
Pentodes and tetrodes can be very good, it's just that they tend to produce too much distortion and have too high an output impedance on their own - so they need some negative feedback to work well (preferably of the local kind). In any case, some tetrodes can make very nice triodes.
Whoa! It looks like you have about seventy 6C4s there, and I can see some other valves which I can't quite make out in the box at the top left of the picture.
Dave is right - the 6C4 is essentially half a 12AU7/ECC82/etc...
Why not try making a massively paralleled amp - maybe something along the lines of the Tim's Hept'AU7 <- why isn't this link working?
Dave is right - the 6C4 is essentially half a 12AU7/ECC82/etc...
Why not try making a massively paralleled amp - maybe something along the lines of the Tim's Hept'AU7 <- why isn't this link working?
Hept'AU7
Hept'AU7
just testing
Hept'AU7
An externally hosted image should be here but it was not working when we last tested it.
just testing
day said:HI
I have 3 of 450TL. can i do SE amp? anybody have circuit
thank you
Sell to a licensed Amateur Radio Operator.
Ebay.
Or better still trade with a licensed Amateur Radio Operator
for some tubes that will fly much better in SE operation:
845
211
etc...
The voltages required are very high with the 450TL and the plate impedance is scary high too - makes for a tough xfmr match...
Not a project for someone who is not clear on the tube and working safely with LETHAL high voltages...
Makes a fine AM ham radio transmitter tube though!
_-_-bear
PS if you were in north america you'd have no trouble finding hams who want and use them class C... if they are good, don't waste them on lamps!
day said:
That is a 4CX250B
4 elements... 4CX----
CX = ceramic & metal
250watts of plate dissipation.
Useful for class C RF or Class AB modulator service.
Very high voltage ~2kv and up.
Not a very good audio tube, but usable in a stable circuit.
Eimac and RCA showed some applications as modulators.
High plate impedance makes it tough though.
FORCED AIR COOLING (noise)
NOT a preamplifier tube!!
Nice tube for RF, a pair will do ~1kW PEP as a linear - the tube is useful up into the VHF spectrum.
Again, sell or trade to a licensed ham radio operator!
_-_-bear
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